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Introduction: Patients with chronic obstructive pulmonary disease (COPD) are frequently colonized and infected by respiratory pathogens. Identifying these infectious etiologies is critical for understanding the microbial dynamics of COPD and for the appropriate use of antimicrobials during exacerbations., Areas Covered: Traditional methods, such as bacterial and viral cultures, have been standard in diagnosing respiratory infections. However, these methods have significant limitations, including lack of sensitivity and prolonged turnaround time. Modern molecular approaches offer rapid, sensitive, and specific detection, though they also come with their own challenges. This review explores and evaluates the clinical utility of the latest advancements in detecting bacterial and viral respiratory infections in COPD, encompassing molecular techniques, biomarkers, and emerging technologies., Expert Opinion: In the evolving landscape of COPD management, integrating molecular diagnostics and emerging technologies holds great promise. The enhanced sensitivity of molecular techniques has significantly advanced our understanding of the role of microbes in COPD. However, many of these technologies have primarily been developed for pneumonia diagnosis or research applications, and their clinical utility in managing COPD requires further evaluation.

Background: Community-acquired lower respiratory tract infection (LRTI) is a common reason for hospitalisation. Antibiotics are frequently used while diagnostic microbiological methods are underutilised in the acute setting., Objectives: We aimed to investigate the relative proportion of viral and bacterial infections in this patient group and explore methods for proper targeting of antimicrobial therapy., Methods: We collected nasopharyngeal samples prospectively from adults hospitalised with LRTIs during three consecutive winter seasons (2016-2019). Syndromic nasopharyngeal testing was performed using a multiplex PCR panel including 16 viruses and four bacteria. Medical records were reviewed for clinical data., Results: Out of 220 included patients, a viral pathogen was detected in 74 (34%), a bacterial pathogen in 63 (39%), both viral and bacterial pathogens in 49 (22%), while the aetiology remained unknown in 34 (15%) cases. The proportion of infections with an identified pathogen increased from 38% to 85% when syndromic testing was added to standard-of-care testing. Viral infections were associated with a low CRP level and absence of pulmonary infiltrates. A high National Early Warning Score did not predict bacterial infections., Conclusions: Syndromic testing by a multiplex PCR panel identified a viral infection or viral/bacterial coinfection in a majority of hospitalised adult patients with community-acquired LRTIs.

Children and adolescents with severe neurological impairment (SNI) require specialized care due to their complex medical needs. In particular, these patients are often affected by severe and recurrent lower respiratory tract infections (LRTIs). These infections, including viral and bacterial etiology, pose a significant risk to these patients, often resulting in respiratory insufficiency and long-term impairments. Using expert consensus, we developed clinical recommendations on the management of LRTIs in children and adolescents with SNI. These recommendations emphasize comprehensive multidisciplinary care and antibiotic stewardship. Initial treatment should involve symptomatic care, including hydration, antipyretics, oxygen therapy, and respiratory support. In bacterial LRTIs, antibiotic therapy is initiated based on the severity of the infection, with aminopenicillin plus a beta-lactamase inhibitor recommended for community-acquired LRTIs and piperacillin-tazobactam for patients with chronic lung disease or tracheostomy. Ongoing management includes regular evaluations, adjustments to antibiotic therapy based on pathogen identification, and optimization of supportive care. Implementation of these recommendations aims to improve the diagnosis and treatment of LRTIs in children and adolescents with SNI. What is Known: • Children and adolescents with severe neurological impairment are particularly affected by severe and recurrent lower respiratory tract infections (LRTIs). • The indication and choice of antibiotic therapy for bacterial LRTI is often difficult because there are no evidence-based treatment recommendations for this heterogeneous but vulnerable patient population; the frequent overuse of broad-spectrum or reserve antibiotics in this patient population increases selection pressure for multidrug-resistant pathogens. What is New: • The proposed recommendations provide a crucial framework for focused diagnostics and treatment of LRTIs in children and adolescents with severe neurological impairment. • Along with recommendations for comprehensive and multidisciplinary therapy and antibiotic stewardship, ethical and palliative care aspects are taken into account., (© 2024. The Author(s).)

Background: The mortality and morbidity rates in children with lower respiratory tract infection (LRTI) remain high., Objective: To describe the number of bacteria that is associated with leukocytes in differential diagnosis of bacterial, mycoplasma, and viral LRTI in children., Methods: Sputum smears were Gram stained for counting single-morphology bacteria associated with leukocytes. The differential diagnostic values of bacterial number were assessed in children with LRTI., Results: The area under the receiver operating characteristic (ROC) curve was 0.95 for bacterial number in the differential diagnosis of bacterial infection from mycoplasma and viral infections. The area under the ROC curve was 0.62 for procalcitonin and 0.94 for bacterial number in the differential diagnosis of bacterial infection from mycoplasma infection., Conclusion: The number of bacteria associated with leukocytes in sputum was valuable and rapid in differential diagnosis of bacterial infection in children with suspected bacterial, mycoplasma, and viral LRTI., (© The Author(s) 2023. Published by Oxford University Press on behalf of American Society for Clinical Pathology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Background: Accuracy and timing of antibiotic therapy remain a challenge for lower respiratory tract infections. New molecular techniques using Multiplex Polymerase Chain Reaction, including the FilmArray® Pneumonia Plus Panel [FAPP], have been developed to address this. The aim of this study is to evaluate the FAPP diagnostic performance for the detection of the 15 typical bacteria of the panel from respiratory samples in a meta-analysis from a systematic review., Methods: We searched PubMed and EMBASE from January 1, 2010, to December 31, 2022, and selected any study on the FAPP diagnostic performance on respiratory samples compared to the reference standard, bacterial culture. The main outcome was the overall diagnostic accuracy with sensitivity and specificity. We calculated the log Diagnostic Odds Ratio and analyzed performance for separate bacteria, antimicrobial resistance genes, and according to the sample type. We also reported the FAPP turnaround time and the out-of-panel bacteria number and species. This study is registered with PROSPERO (CRD42021226280)., Results: From 10 317 records, we identified 30 studies including 8 968 samples. Twenty-one were related to intensive care. The overall sensitivity and specificity were 94% [95% Confidence Interval (CI) 91-95] and 98% [95%CI 97-98], respectively. The log Diagnostic Odds Ratio was 6.35 [95%CI 6.05-6.65]. 9.3% [95%CI 9.2-9.5] of bacteria detected in culture were not included in the FAPP panel., Conclusion: This systematic review reporting the FAPP evaluation revealed a high accuracy. This test may represent an adjunct tool for pulmonary bacterial infection diagnostic and antimicrobial stewardship. Further evidence is needed to assess the impact on clinical outcome., (Copyright © 2023 Société française d'anesthésie et de réanimation (Sfar). Published by Elsevier Masson SAS. All rights reserved.)

Objectives: To assess the performance of a test (called BV), integrating the blood levels of three immune proteins into a score, to differentiate bacterial from viral infection among adults with suspected lower respiratory tract infection (LRTI)., Methods: Prospective diagnostic accuracy study, enrolling febrile adults >18 years with LRTI signs or symptoms for less than 7 days presenting to several hospitals' emergency departments in Israel. The main exclusion criterion was immunodeficiency. Reference standard diagnosis (bacterial/viral/indeterminate) was based on three experts independently reviewing comprehensive patient data including follow-up data. BV generated three results: viral infection or other nonbacterial condition (0 ≤ score < 35), equivocal (35 ≤ score ≤ 65) and bacterial infection including co-infection (65 < score ≤ 100). BV performance was assessed against the reference standard with indeterminate reference standard and equivocal BV cases removed., Results: Of 490 enrolled patients, 415 met eligibility criteria (median age 56 years, interquartile range 35). The reference standard classified 104 patients as bacterial, 210 as viral and 101 as indeterminate. BV was equivocal in 9.6% (30/314). Excluding indeterminate reference standard diagnoses and equivocal BV results, BV's sensitivity for bacterial infection was 98.1% (101/103; 95% confidence interval 95.4-100), specificity 88.4% (160/181; 83.7-93.1) and negative predictive value 98.8% (160/162; 97.1-100)., Discussion: BV exhibited high diagnostic performance for febrile adults with suspected LRTI among patients with reference standard diagnoses of bacterial or viral LRTI., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objectives: We aimed at assessing the efficacy and safety on antibiotic exposure of a strategy combining a respiratory multiplex PCR (mPCR) with enlarged panel and daily procalcitonin (PCT) measurements, as compared with a conventional strategy, in adult patients who were critically ill with laboratory-confirmed SARS-CoV-2 pneumonia., Methods: This multicentre, parallel-group, open-label, randomized controlled trial enrolled patients admitted to 13 intensive care units (ICUs) in France. Patients were assigned (1:1) to the control strategy, in which antibiotic streamlining remained at the discretion of the physicians, or interventional strategy, consisting of using mPCR and daily PCT measurements within the first 7 days of randomization to streamline initial antibiotic therapy, with antibiotic continuation encouraged when PCT was >1 ng/mL and discouraged if < 1 ng/mL or decreased by 80% from baseline. All patients underwent conventional microbiological tests and cultures. The primary end point was antibiotic-free days at day 28., Results: Between April 20th and November 23rd 2020, 194 patients were randomized, of whom 191 were retained in the intention-to-treat analysis. Respiratory bacterial co-infection was detected in 48.4% (45/93) and 21.4% (21/98) in the interventional and control group, respectively. The number of antibiotic-free days was 12.0 (0.0; 25.0) and 14.0 (0.0; 24.0) days, respectively (difference, -2.0, (95% CI, -10.6 to 6.6), p=0.89). Superinfection rates were high (51.6% and 48.5%, respectively). Mortality rates and ICU lengths of stay did not differ between groups., Discussion: In severe SARS-CoV-2 pneumonia, the mPCR/PCT algorithm strategy did not affect 28-day antibiotics exposure nor the major clinical outcomes, as compared with routine practice., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Objectives: To identify demographic and clinical characteristics of children with fever and/or respiratory illness associated with a diagnosis of bacterial tracheostomy-associated respiratory tract infections (bTARTI). Secondary objectives included comparison of diagnostic testing, length of stay (LOS), and readmission rates between children diagnosed with bTARTI and others., Methods: We performed a retrospective chart review of encounters over 1 year for fever and/or respiratory illness at a single academic children's hospital for children with tracheostomy dependence. Patient characteristics, features of presenting illness, and laboratory and imaging results were collected. Generalized linear mixed models were employed to study associations between patient characteristics, diagnosis of bTARTI, and impact on LOS or readmission rates., Results: Among 145 children with tracheostomies identified, 79 children contributed 208 encounters. bTARTI was diagnosed in 66 (31.7%) encounters. Significant associations with bTARTI diagnosis included chest radiograph consistent with bacterial pneumonia (odds ratio [OR], 1.77; 95% confidence interval [CI], 1.50-2.08), positive tracheal aspirate culture (OR, 1.3; 95% CI, 1.05-1.61), higher white blood cell count (16.4 vs 13.1 × 103/µ; P = .03), change in oxygen requirement (OR, 1.14; 95% CI, 1.00-1.31), telephone encounter (OR, 1.41; 95% CI, 1.09-1.81), and living at home with family (OR, 1.42; 95% CI, 1.06-1.92). LOS for admitted patients with bTARTI was 2.19 times longer (CI, 1.23-3.88)., Conclusions: In our single-center study, we identified several clinical and nonclinical factors associated with a diagnosis of bTARTI. Despite widespread use, few laboratory tests were predictive of a diagnosis of bTARTI. There is need for standardization in diagnosis., (Copyright © 2023 by the American Academy of Pediatrics.)

Objective: To explore the diagnostic value of combined detection of serum amyloid A (SAA), C-reactive protein (CRP) and procalcitonin (PCT) in children with bacteria or non-bacterial respiratory tract infection., Methods: 200 children with respiratory tract infections diagnosed in our hospital were included in the study. According to the results of the aetiological examination, they were divided into bacterial infection group and non-bacterial infection group. At the same time, 100 healthy children admitted to the hospital for physical examination during the same period were selected as the healthy subjects control group. Changes in serum SAA, PCT and CRP in three groups were compared. Comparison of a positive rate of the single index and combined detection were performed. Children with bacterial infections were treated with conventional antibiotics. The changes in serum SAA, PCT and CRP in the infection group before and after treatment were compared. The efficacy of SAA, PCT and CRP alone and in combination was compared., Results: The serum SAA, PCT and CRP levels in the bacterial infection group were higher than those in the non-bacterial infection group and healthy children, and the differences were statistically significant. The positive detection rates and combined detection rates of serum SAA, PCT and CRP in the bacterial infection group were higher than those in the non-bacterial infection group and the healthy subject's control group. After conventional antibiotic treatment, serum SAA, PCT and CR levels in children with bacterial infection were significantly decreased., Conclusion: The combined detection based on SAA, CRP and PCT can effectively identify and diagnose respiratory tract infection in children, providing a certain reference for the promotion of the diagnostic scheme. Key messagesSerum SAA, PCT and CRP were highly expressed in children with respiratory tract infection, and the expression level was the highest in children with bacterial pneumonia.The combined detection of serum SAA, CRP and PCT indicators have higher diagnostic efficiency and can effectively make a differential diagnosis of respiratory tract infection in children.

Background: Antimicrobial resistance (AMR) is rising at an alarming rate and complicating the management of infectious diseases including lower respiratory tract infections (LRTI). Metagenomic next-generation sequencing (mNGS) is a recently established method for culture-independent LRTI diagnosis, but its utility for predicting AMR has remained unclear. We aimed to assess the performance of mNGS for AMR prediction in bacterial LRTI and demonstrate proof of concept for epidemiological AMR surveillance and rapid AMR gene detection using Cas9 enrichment and nanopore sequencing., Methods: We studied 88 patients with acute respiratory failure between 07/2013 and 9/2018, enrolled through a previous observational study of LRTI. Inclusion criteria were age ≥ 18, need for mechanical ventilation, and respiratory specimen collection within 72 h of intubation. Exclusion criteria were decline of study participation, unclear LRTI status, or no matched RNA and DNA mNGS data from a respiratory specimen. Patients with LRTI were identified by clinical adjudication. mNGS was performed on lower respiratory tract specimens. The primary outcome was mNGS performance for predicting phenotypic antimicrobial susceptibility and was assessed in patients with LRTI from culture-confirmed bacterial pathogens with clinical antimicrobial susceptibility testing (n = 27 patients, n = 32 pathogens). Secondary outcomes included the association between hospital exposure and AMR gene burden in the respiratory microbiome (n = 88 patients), and AMR gene detection using Cas9 targeted enrichment and nanopore sequencing (n = 10 patients)., Results: Compared to clinical antimicrobial susceptibility testing, the performance of respiratory mNGS for predicting AMR varied by pathogen, antimicrobial, and nucleic acid type sequenced. For gram-positive bacteria, a combination of RNA + DNA mNGS achieved a sensitivity of 70% (95% confidence interval (CI) 47-87%) and specificity of 95% (CI 85-99%). For gram-negative bacteria, sensitivity was 100% (CI 87-100%) and specificity 64% (CI 48-78%). Patients with hospital-onset LRTI had a greater AMR gene burden in their respiratory microbiome versus those with community-onset LRTI (p = 0.00030), or those without LRTI (p = 0.0024). We found that Cas9 targeted sequencing could enrich for low abundance AMR genes by > 2500-fold and enabled their rapid detection using a nanopore platform., Conclusions: mNGS has utility for the detection and surveillance of resistant bacterial LRTI pathogens., (© 2022. The Author(s).)

Background: Antibiotic resistance is a global health challenge and the close correlation between antibiotic use and the development of resistance makes it essential to maintain a rational use of antibiotics. Most antibiotics are prescribed in general practice against acute respiratory tract infections (ARTI), even though most of these infections are of viral etiology. Thus, a safe method to substantially reduce unnecessary use of antibiotics in general practice is needed. Procalcitonin (PCT) is a precursor protein with very low circulating levels in the blood under physiological conditions. However, in response serious bacterial infection the level of PCT in the blood may increase significantly. Until recently, quantitative analyses of PCT was performed in hospital laboratories, impeding the implementation of PCT in primary care. Our aim is to determine whether it is possible to lower the use of antibiotics in patients presenting with symptoms of ARTI, without significantly prolonging the period of illness, by using a newly released PCT point-of-care test in general practice., Methods: The Procalcitonin-Guided Antibiotics in Respiratory Infections (PARI) study is a randomized, single-blinded, non-inferiority, multi-practice intervention study comparing a PCT-group to a control group. Patients (N = 508) will be randomly assigned 1:1 to standard care or to the PCT group. The primary outcomes the duration of illness and symptoms from ARTI measured with the Acute Respiratory Tract Infection Questionnaire. Secondary outcomes include (1) Number of participants in each trial arm exposed to antibiotic treatment at index consultation (day 1) and within 30 days, (2) Number of participants in each trial arm with side effects from antibiotic treatment within 14 days, (3) Number of participants in each trial arm with re-consultations within 30 days, (4) Number of participants in each trial arm admitted to hospital (including diagnosis and mortality) within 30 days, (5) Characterization of biomarker (CRP and PCT) level at index consultation. Tertiary outcomes include patient and general practitioner satisfaction with the use of the PCT point-of-care test, and long-term follow-up., Discussion: To our knowledge, this is the first study to examine a PCT point-of-care test in general practice with the aim of reducing the use of antibiotics in patients with symptoms of ARTI. Results of this study may prove important in targeting antibiotic treatment only to those patients who need it, thus contributing to limiting the spread of antibiotic resistance., Trial Registration: ClinicalTrials.gov Identifier: NCT04216277 , date of registration: 2. of January 2020., (© 2022. The Author(s).)

To investigate the role of the triple combination serum heparin-binding protein (HBP), procalcitonin (PCT), and C-reactive protein (CRP) in children with acute bacterial upper respiratory tract infection (ABURTI). A total of 130 children with upper respiratory tract infection admitted to the Department of Pediatrics of Fujian Maternity and Child Health Hospital from September 2019 to January 2021 were selected as the research group. According to the results of pathogenic analysis, children were further subdivided into a bacterial infection group ( n  = 67) and a viral infection group ( n  = 63). Additionally, 65 children who underwent physical examinations in our hospital during the same period were collected and included into the control group ( n  = 65). All patients selected were treated with cefixime granules orally for 5 days. Serum HBP level, serum PCT level, and serum CRP level were measured by double antibody Sandwich Enzyme Linked Immunosorbent Assay (ELISA), fluorescence method, and immunoturbidimetric assay, respectively. The expression levels of the three indicators in the serum of all subjects were compared, and the receiver operating characteristic (ROC) curve was used to analyze their diagnostic value in children with ABURTI. Furthermore, according to clinical efficacy of children with bacterial infections, they were divided into a good efficacy group (markedly effective) and a poor efficacy group (effective + ineffective) to compare serum HBP, PCT, and CRP levels between the two groups. The ROC curve was drawn to analyze the value of the three indicators in predicting the curative effect in children with ABURTI. Pearson test was used to analyze the correlation among the expression of HBP, PCT, and CRP. Results showed that the expression levels of HBP, PCT, and CRP in the serum of children in the bacterial infection group were significantly higher than those in the other two groups. The positive rates of HBP, PCT, and CRP in children in the bacterial infection group were also significantly higher than those of the other two groups. The area under the curve (AUC) of the combined diagnosis of HBP, PCT, and CRP was 0.973, which was significantly higher than that of the single detection by any of the three indicators, which were 0.849, 0.819, and 0.854, respectively. The expression levels of HBP, PCT, and CRP in the serum of children in the good efficacy group were significantly lower than those in the poor efficacy group, and the AUC of the triple combination for predicting treatment efficacy was 0.959. Pearson test showed that there was a positive correlation between the serum expression of HBP, PCT, and CRP in children. HBP, PCT, and CRP were highly correlated in children with ABURTI, and their combined detection was of high diagnostic value among ABURTI patients, indicating that the three were expected to become potential indicators for efficacy prediction., Competing Interests: The authors declare that there are no conflicts of interest., (Copyright © 2022 Xiuqin Yang et al.)

The frequencies of 19 respiratory pathogens other than SARS-CoV-2 were assessed in 6,"?>235 Brazilian individuals tested for COVID-19. Overall, only 83 individuals who tested positive for SARS-CoV-2 had codetection of other pathogens. Individuals infected with Rhinovirus/Enterovirus, Human Coronavirus (HCoV)-HKU1, HCoV-NL63, HPIV-4, Influenza A (-H1N1 and other subtypes), Influenza B, Human Respiratory Syncytial Virus and Human Metapneumovirus were less likely to test positive for SARS-CoV-2. Infection with Streptococcys pyogenes, Chlamydophila pneumoniae, Mycoplasma pneumoniae, and Bordetella pertussis were more frequent in individuals who tested negative for SARS-CoV-2, but without significancy. We found 150 individuals infected with ≥2 pathogens other than SARS-CoV-2, only 3 out of whom tested positive for COVID-19. The codetection frequency was low in individuals diagnosed with COVID-19. Other viral infections may provide a cross-reactive, protective immune response against SARS-CoV-2. Screening for bacterial respiratory infections upon COVID-19 testing is important to drive suitable therapeutic approaches and avoid unnecessary antibiotic prescription., Competing Interests: Declaration of competing interest The authors report no conflicts of interest relevant to this article., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Objectives: Respiratory syncytial virus (RSV) in pediatric patients has been associated with low risk of concomitant bacterial infection. However, in children with severe disease, it occurs in 22% to 50% of patients. As viral testing becomes routine, bacterial codetections are increasingly identified in patients with non-RSV viruses. We hypothesized, among patients intubated for respiratory failure secondary to suspected infection, there are similar rates of codetection between RSV and non-RSV viral detections., Methods: This retrospective chart review, conducted over a 5-year period, included all patients younger than 2 years who required intubation secondary to respiratory failure from an infectious etiology in a single pediatric emergency department. Patients intubated for noninfectious causes were excluded., Results: We reviewed 274 patients, of which 181 had positive viral testing. Of these, 48% were RSV-positive and 52% were positive for viruses other than RSV. Codetection of bacteria was found in 76% (n = 65; 95% confidence interval [CI], 66%, 84%) of RSV-positive patients and 66% (n = 63, 95% CI: 57%, 76%) of patients positive with non-RSV viruses. Among patients with negative viral testing, 33% had bacterial growth on lower respiratory culture. Male sex was the only patient-related factor associated with increased odds of codetection (odds ratio [OR], 2.2; 95% CI, 1.08-4.38). The odds of codetection between RSV-positive patients and non-RSV viruses were not significantly different (OR, 1.3; 95% CI, 0.62-2.71)., Conclusions: Bacterial codetection is common and not associated with anticipated patient-related factors or with a specific virus. These results suggest consideration of empiric antibiotics in infants with respiratory illness requiring intubation., Competing Interests: Disclosure: The authors declare no conflict of interest., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Adult patients with hematological malignancies are frequently accompanied by bacterial infections in the lungs when they are first diagnosed. Sputum culture, procalcitonin (PCT), C-reactive protein (CRP), body temperature, and other routinely used assays are not always reliable. Cytokines are frequently abnormally produced in adult hematological malignancies associated with a lung infection, it is uncertain if cytokines can predict lung bacterial infections in individuals with hematological malignancies. Therefore, we reviewed 541 adult patients newly diagnosed with hematological malignancies, of which 254 patients had lung bacterial infections and 287 patients had no other clearly diagnosed infections. To explore the predictive value of cytokines for pulmonary bacterial infection in adult patients with hematological malignancies. Our results show that IL-4, IL-6, IL-8, IL-10, IL-12P70, IL-1β, IL-2, IFN-γ, TNF-α, TNF-β and IL-17A are in the lungs The expression level of bacterially infected individuals was higher than that of patients without any infections (P<0.05). Furthermore, we found that 88.89% (200/225) of patients with IL-6 ≥34.12 pg/ml had a bacterial infection in their lungs. With the level of IL-8 ≥16.35 pg/ml, 71.67% (210/293) of patients were infected. While 66.10% (193/292) of patients had lung bacterial infections with the level of IL-10 ≥5.62 pg/ml. When IL-6, IL-8, and IL-10 were both greater than or equal to their Cutoff-value, 98.52% (133/135) of patients had lung bacterial infection. Significantly better than PCT ≥0.11 ng/ml [63.83% (150/235)], body temperature ≥38.5°C [71.24% (62/87)], CRP ≥9.3 mg/L [53.59% (112/209)] the proportion of lung infection. In general. IL-6, IL-8 and IL-10 are abnormally elevated in patients with lung bacterial infections in adult hematological malignancies. Then, the abnormal increase of IL-6, IL-8 and IL-10 should pay close attention to the possible lung bacterial infection in patients., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Li, Yang, Hu, Guan, Zhang, Zhang, Yang, Zhang and Zhao.)

Background: There is a lack of studies comparing PCT, CRP and WBC levels in the differential diagnosis of acute bacterial, viral, and mycoplasmal respiratory tract infections. It is necessary to explore the correlation between above markers and different types of ARTI., Methods: 108 children with confirmed bacterial infection were regarded as group A, 116 children with virus infection were regarded as group B, and 122 children with mycoplasmal infection were regarded as group C. The levels of PCT, CRP and WBC of the three groups were detected and compared., Results: The levels of PCT, CRP and WBC in group A were significantly higher than those in groups B and C (p < 0.05). The positive rate of combined detection of PCT, CRP and WBC was significant higher than that of single detection. There was no significant difference in PCT, CRP and WBC levels between the group of G + bacterial infection and G - bacterial infection (p > 0.05). ROC curve results showed that the AUC of PCT, CRP and WBC for the diagnosis of bacterial respiratory infections were 0.65, 0.55, and 0.58, respectively., Conclusions: PCT, CRP and WBC can be combined as effective indicators for the identification of acute bacterial or no-bacterial infections in children. The levels of PCT and CRP have higher differential diagnostic value than that of WBC in infection, and the combined examination of the three is more valuable in clinic., (© 2021. The Author(s).)

SARS-CoV-2 antibody assays are used for epidemiological studies and for the assessment of vaccine responses in highly vulnerable patients. So far, data on cross-reactivity of SARS-CoV-2 antibody assays is limited. Here, we compared four enzyme-linked immunosorbent assays (ELISAs; Vircell SARS-CoV-2 IgM/IgA and IgG, Euroimmun SARS-CoV-2 IgA and IgG) for detection of anti-SARS-CoV-2 antibodies in 207 patients with COVID-19, 178 patients with serological evidence of different bacterial infections, 107 patients with confirmed viral respiratory disease, and 80 controls from the pre-COVID-19 era. In COVID-19 patients, the assays showed highest sensitivity in week 3 (Vircell-IgM/A and Euroimmun-IgA: 78.9% each) and after week 7 (Vircell-IgG: 97.9%; Euroimmun-IgG: 92.1%). The antibody indices were higher in patients with fatal disease. In general, IgM/IgA assays had only limited or no benefit over IgG assays. In patients with non-SARS-CoV-2 respiratory infections, IgG assays were more specific than IgM/IgA assays, and bacterial infections were associated with more false-positive results than viral infections. The specificities in bacterial and viral infections were 68.0 and 81.3% (Vircell-IgM/IgA), 84.8 and 96.3% (Euroimmun-IgA), 97.8 and 86.0% (Vircell-IgG), and 97.8 and 99.1% (Euroimmun-IgG), respectively. Sera from patients positive for antibodies against Mycoplasma pneumoniae, Chlamydia psittaci, and Legionella pneumophila yielded particularly high rates of unspecific false-positive results in the IgM/IgA assays, which was revealed by applying a highly specific flow-cytometric assay using HEK 293 T cells expressing the SARS-CoV-2 spike protein. Positive results obtained with anti-SARS-CoV-2 IgM/IgA ELISAs require careful interpretation, especially if there is evidence for prior bacterial respiratory infections., (© 2021. The Author(s).)

Background: Acute respiratory tract infections (RTIs) are the most common reason to seek medical care, with many patients receiving inappropriate antibiotics. Novel testing approaches to identify aetiology at the point-of-care are required to accurately guide antibiotic treatment., Objective: To assess the diagnostic accuracy of biomarker combinations to rapidly differentiate between acute bacterial or viral RTI aetiology., Data Sources: MEDLINE, Embase and Web of Science databases were searched to February 2021., Study Eligibility Criteria: Diagnostic accuracy studies comparing accuracy of point-of-care and rapid diagnostic tests in primary or secondary care, consisting of biomarker combinations, to identify bacterial or viral aetiology of RTI., Methods: Risk of bias was assessed using the QUADAS-2 tool. Sensitivity and specificity of tests reported by more than one study were meta-analysed using a random effects model., Results: Twenty observational studies (3514 patients) were identified. Eighteen were judged at high risk of bias. For bacterial aetiologies, sensitivity ranged from 61% to 100% and specificity from 18% to 96%. For viral aetiologies, sensitivity ranged from 59% to 97% and specificity from 74% to 100%. Studies evaluating two commercial tests were meta-analysed. For ImmunoXpert, the summary sensitivity and specificity were 85% (95% CI 75%-91%, k = 4) and 86% (95% CI 73%-93%, k = 4) for bacterial infections, and 90% (95% CI 79%-96%, k = 3) and 92% (95% CI 83%-96%, k = 3) for viral infections, respectively. FebriDx had pooled sensitivity and specificity of 84% (95% CI 75%-90%, k = 4) and 93% (95% CI 90%-95%, k = 4) for bacterial infections, and 87% (95% CI 72%-95%; k = 4) and 82% (95% CI 66%-86%, k = 4) for viral infections, respectively., Conclusion: Combinations of biomarkers show potential clinical utility in discriminating the aetiology of RTIs. However, the limitations in the evidence base, due to a high proportion of studies with high risk of bias, preclude firm conclusions. Future research should be in primary care and evaluate patient outcomes and cost-effectiveness with experimental study designs., Clinical Trial: PROSPERO registration number: CRD42020178973., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Respiratory tract infections (RTIs) drive many outpatient encounters and, despite being predominantly viral, are associated with high rates of antibiotic prescriptions. With rising antibacterial resistance, optimization of prescribing of antibiotics in outpatients with RTIs is a critical need. Fortunately, this challenge arises at a time of increasing availability of novel RTI diagnostics to help discern which patients have bacterial infections warranting treatment. Effective implementation of antibiotic stewardship is needed, but optimal approaches for ambulatory settings are unknown. Future research needs are reviewed in this summary of a research summit convened by the Infectious Diseases Society of America in the fall of 2019., (© The Author(s) 2020. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Background and Objectives: Long-term prophylactic antibiotics are often used to prevent bacterial infections. However, supporting evidence for this is not always robust. Including parents in decisions relating to medication is key to medicines optimisation. Parental concern regarding medication is a major determinant of poor adherence. This study explores parental experiences of having a child prescribed prophylactic antibiotics and how that affects their antibiotic use behaviour., Methods: We conducted a prospective, single-centre, exploratory, qualitative study at Sheffield Children's Hospital. Through 15 interviews, involving 18 participants, we explored parental 'lived experiences' and attitudes towards azithromycin prophylaxis prescribed for various respiratory conditions. Thematic analysis was conducted., Results: The overriding factor influencing parental decisions about the uptake of antibiotic prophylaxis is wanting their child to be well now. The main concern voiced by parents is that of antibiotic resistance given their children are high users of antibiotics. This is however seen as a problem for the future, not the present. Preparing families adequately helps prevent practical difficulties relating to medication. Facilitating 'normalisation' of prophylaxis through daily routines and minimising disruption to the family environment may reduce parental anxiety, promote adherence and result in easing of potential restrictions to the child's daily activities., Conclusion: Grounded in our deeper understanding, we propose a behavioural model that describes phases parents go through while having a child on prophylactic antibiotics. Time invested in holistically addressing the parental experience and having an awareness of potential issues parents face, may facilitate medication adherence, reduce anxieties and improve doctor-parent relationships., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction: lower respiratory tract infections (LRTIs) are infections involving the trachea, primary bronchi and lungs. People with LRTIs typically experience coughs as the primary symptoms; however, shortness of breath, weakness, fever and fatigue may be coupled with the cough. It is common among the aged, children under five and the immune-suppressed. Persons with symptoms suggestive of pulmonary tuberculosis (TB) may have tuberculosis, other respiratory tract infection or co-infection of tuberculosis and other respiratory pathogens. This study aimed to identify the presence of pathogens in sputum of suspected tuberculosis cases and their antimicrobial resistance patterns., Methods: this was a retrospective study conducted from September 2018 to November 2019 at Tamale Public Health Laboratory. Sputum or gastric lavage samples were collected from persons with suspected clinical presentations of TB and/or LRTI. These samples were cultured using standard microbiological protocols and antimicrobial susceptibility test performed on the positive cultures by Kirby-Bauer disc diffusion method. Molecular identification of M. tuberculosis was performed on all the suspected TB cases using GeneXpert mycobacterium tuberculosis/rifampin (MTB/RIF) assay., Results: during the study period, there were 264 cases of which 49.2% were males and 50.8% were females. Positive cases for culture were 47.3%. Out of the 264 cases, 186 (70.5%) were suspected TB with 51.6% being positive for culture, 6.5% positive for M. tuberculosis (GeneXpert confirmed) and 3.8% co-infection of TB with other bacteria pathogens. Klebsiella spp. (35/125; 28%) and Pseudomonas spp. (19/125; 15.2%) were the most predominant pathogens isolated. There was no significant difference in detection of bacteria in males and females (p=0.89), however individuals with suspected TB were significantly infected with other bacterial species than the unsuspected individuals (p=0.03). Almost all the isolates showed high susceptibility towards carbapenem (meropenem) and high resistance towards the third generation cephalosporins (cefotaxime and ceftriaxone)., Conclusion: this study highlights the need to test individuals with classical symptoms of LRTIs for other bacterial infections other than TB only. Sputum culture is recommended for all suspected tuberculosis cases to provide accurate laboratory diagnosis to LRTIs and mitigate unnecessary use of antimicrobials., Competing Interests: The authors declare no competing interests., (Copyright: Oliver Deberu et al.)

Objectives: Areas with declining malaria transmission in sub-Saharan Africa have recently witnessed important changes in the aetiology of childhood acute febrile illness (AFI). We describe the aetiology of AFI in a high malaria transmission area in rural Burkina Faso., Methods: In a prospective hospital-based diagnostic study, children aged 3 months to 15 years with AFI were recruited and assessed using a systematic diagnostic protocol, including blood cultures, whole blood PCR on a selection of bacterial pathogens, malaria diagnostics and a multiplex PCR on nasopharyngeal swabs targeting 21 viral and 4 bacterial respiratory pathogens., Results: A total of 589 children with AFI were enrolled from whom an infectious disease was considered in 575 cases. Acute respiratory tract infections, malaria and invasive bacterial infections (IBI) accounted for 179 (31.1%), 175 (30.4%) and 75 (13%) of AFI cases respectively; 16 (21.3%) of IBI cases also had malarial parasitaemia. A viral pathogen was demonstrated from the nasopharynx in 157 children (90.7%) with respiratory tract symptoms. Of all children with viral respiratory tract infections, 154 (92.4% received antibiotics, whereas no antibiotic was provided in 13 (17%) of IBI cases., Conclusions: Viral respiratory infections are a common cause of childhood AFI in high malaria transmission areas, next to malaria and IBI. These findings highlight the importance of interventions to improve targeted treatment with antimicrobials. Most patients with viral infections received antibiotics unnecessarily, while a considerable number with IBI did not receive antibiotics., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease. Several risk factors such as smoking, air pollution, inhaled toxins, high body mass index and infectious agents are involved in the pathogenesis of IPF. In the present study, this meta-analysis study investigates the prevalence of viral and bacterial infections in the IPF patients and any possible association between these infections with pathogenesis of IPF., Methods: The authors carried out this systematic literature review from different reliable databases such as PubMed, ISI Web of Science, Scopus and Google Scholar to December 2020.Keywords used were the following "Idiopathic pulmonary fibrosis", "Infection", "Bacterial Infection" and "Viral Infection", alone or combined together with the Boolean operators "OR", "AND" and "NOT" in the Title/Abstract/Keywords field. Pooled proportion and its 95% CI were used to assess the prevalence of viral and bacterial infections in the IPF patients., Results: In this systematic review and meta-analyses, 32 studies were selected based on the exclusion/inclusion criteria. Geographical distribution of included studies was: eight studies in American people, 8; in European people, 15 in Asians, and one in Africans. The pooled prevalence for viral and bacterial infections w ere 53.72% (95% CI 38.1-69.1%) and 31.21% (95% CI 19.9-43.7%), respectively. The highest and lowest prevalence of viral infections was HSV (77.7% 95% CI 38.48-99.32%), EBV (72.02%, 95% CI 44.65-90.79%) and Influenza A (7.3%, 95% CI 2.66-42.45%), respectively. Whereas the highest and lowest prevalence in bacterial infections were related to Streptococcus sp. (99.49%, 95% CI 96.44-99.9%) and Raoultella (1.2%, 95% CI 0.2-3.08%), respectively., Conclusions: The results of this review were confirmed that the presence of viral and bacterial infections are the risk factors in the pathogenesis of IPF. In further analyses, which have never been shown in the previous studies, we revealed the geographic variations in the association strengths and emphasized other methodological parameters (e.g., detection method). Also, our study supports the hypothesis that respiratory infection could play a key role in the pathogenesis of IP.

Fever is one of the most common reasons for pediatric consultation in Africa. Malaria incidence has now dropped considerably, yet etiologies of non-malarial febrile diseases are poorly documented. This pilot study aimed to 1) identify pathogens potentially associated with non-malarial fever in children younger than 10 years in the suburbs of Dakar and 2) describe the epidemiological characteristics of these patients. During the study period, all eligible children (< 10 years of age, body temperature ≥ 38°C, negative result for the malaria rapid diagnostic test, living in Guediawaye/Pikine for the previous four calendar months, not receiving any anti-infectious treatment since the onset of fever, and with parent's consent to participate) presenting to the health post in Medina Gounass located in Guediawaye on Mondays and Fridays were included. In total, 106 children participated in the study, and PCR from nasopharyngeal swabs, hemoculture, C-reactive protein, blood cell counts, and quantitative buffy coat from blood samples and coproculture from stool samples were performed. In 70 (66%) children, at least one pathogen was isolated. Viruses were identified in 55 children, most commonly enteroviruses, rhinoviruses, and adenoviruses, and dengue virus was identified in three children. Only five children had bacterial infections, and 10 had bacterial and viral coinfections. Ninety-seven children (92%) received prescription for antibiotics. Many strains of bacteria were found to be resistant to several antibiotics. Despite limitations, this pilot study showed that pathogens potentially associated with non-malarial fever in children younger than 10 years near Dakar were predominantly viruses, most commonly upper respiratory infections, although bacteria accounted for a small proportion.

Competing Interests: Competing interests The BMJ has judged that there are no disqualifying financial ties to commercial companies. The authors declare the following other interests: none. Further details of The BMJ policy on financial interests are here: https://www.bmj.com/about-bmj/resources-authors/forms-policies-and-checklists/declaration-competing-interests

Background: Bronchiectasis is a multidimensional lung disease characterized by bronchial dilation, chronic inflammation, and infection. The FACED (Forced expiratory volume in 1 s (FEV1), Age, Chronic colonization, Extension, and Dyspnea) score and Bronchiectasis Severity Index (BSI) are used to stratify disease risk and guide clinical practice. This meta-analysis aimed to quantify the accuracy of these two systems for predicting bronchiectasis outcomes., Methods: PubMed, Embase, and the Cochrane Database of Systematic Reviews were searched for relevant studies. Quality of included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) criteria. Pooled summary estimates, including sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were calculated. Summary receiver operating characteristic curves were constructed, and the area under the curve (AUC) was used to evaluate prognostic performance., Results: We analyzed 17 unique cohorts (6525 participants) from ten studies. FACED scores with a cut-off value ≥ 5 predicted all-cause mortality better than BSI with a cut-off value ≥ 9, based on pooled sensitivity (0.34 vs 0.7), specificity (0.94 vs 0.66), PLR (4.76 vs 2.05), NLR (0.74 vs 0.48), DOR (6.67 vs 5.01), and AUC (0.87 vs 0.75). Both FACED scores with a cut-off value ≥ 5 (AUC = 0.82) and BSI scores with a cut-off value ≥ 5 or 9 (both AUC = 0.80) help to predict hospitalization., Conclusions: At a cut-off value ≥ 5, FACED scores can reliably predict all-cause mortality and hospitalization, while BSI scores can reliably predict hospitalization with a cut-off of ≥5 or ≥9. Further studies are essential to validate the prognostic performance of these two scores., (© 2020 The Author(s).)

Objectives: To investigate the incidence of bacterial and fungal coinfection of hospitalized patients with confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in this retrospective observational study across two London hospitals during the first UK wave of coronavirus disease 2019 (COVID-19)., Methods: A retrospective case series of hospitalized patients with confirmed SARS-CoV-2 by PCR was analysed across two acute NHS hospitals (20 February-20 April 2020; each isolate reviewed independently in parallel). This was contrasted to a control group of influenza-positive patients admitted during the 2019-2020 flu season. Patient demographics, microbiology and clinical outcomes were analysed., Results: A total of 836 patients with confirmed SARS-CoV-2 were included; 27 (3.2%) of 836 had early confirmed bacterial isolates identified (0-5 days after admission), rising to 51 (6.1%) of 836 throughout admission. Blood cultures, respiratory samples, pneumococcal or Legionella urinary antigens and respiratory viral PCR panels were obtained from 643 (77%), 110 (13%), 249 (30%), 246 (29%) and 250 (30%) COVID-19 patients, respectively. A positive blood culture was identified in 60 patients (7.1%), of which 39 were classified as contaminants. Bacteraemia resulting from respiratory infection was confirmed in two cases (one each community-acquired Klebsiella pneumoniae and ventilator-associated Enterobacter cloacae). Line-related bacteraemia was identified in six patients (three Candida, two Enterococcus spp. and one Pseudomonas aeruginosa). All other community-acquired bacteraemias (n = 16) were attributed to nonrespiratory infection. Zero concomitant pneumococcal, Legionella or influenza infection was detected. A low yield of positive respiratory cultures was identified; Staphylococcus aureus was the most common respiratory pathogen isolated in community-acquired coinfection (4/24; 16.7%), with pseudomonas and yeast identified in late-onset infection. Invasive fungal infections (n = 3) were attributed to line-related infections. Comparable rates of positive coinfection were identified in the control group of confirmed influenza infection; clinically relevant bacteraemias (2/141; 1.4%), respiratory cultures (10/38; 26.3%) and pneumococcal-positive antigens (1/19; 5.3%) were low., Conclusions: We found a low frequency of bacterial coinfection in early COVID-19 hospital presentation, and no evidence of concomitant fungal infection, at least in the early phase of COVID-19., (Copyright © 2020 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

The 2020 Global Initiative for Obstructive Lung Disease (GOLD) Report highlights the importance of sputum purulence in the decision to prescribe antibiotics for acute exacerbations. The purpose of this systematic review and meta-analysis was to evaluate the strength of literature supporting inclusion of sputum purulence in criteria utilized to evaluate if antimicrobials are indicated in acute COPD exacerbation. A total of 6 observational studies met inclusion criteria for this meta-analysis. Sputum purulence was defined by visual assessment of color, either subjectively by providers and/or patients or by a colored chart, where green or yellow sputum was considered purulent. Four of the studies were primarily conducted in hospitalized patients, one in the emergency department, and one in the primary care setting. Five studies relied upon expectorated sputum and one used bronchoscopy to obtain sputum samples for bacterial cultures. Compared with mucoid sputum, purulent sputum had a significantly higher probability of positive bacterial culture results (RR = 2.14, 95%CI [1.25, 3.67], p  = 0.006, moderate quality). For sensitivity analysis, after removal of studies losing 2 or more points from the New Castle-Ottawa scale, the effect value remained statistically significant. This systematic review and meta-analysis showed a moderate level of evidence that purulent sputum during COPD exacerbation, as defined by yellow or green color, is associated with a significantly higher probability of potentially pathogenic bacteria, supporting GOLD report and NICE recommendations.

Background: Diversified etiology of lower respiratory tract infection renders diagnosis challenging. The mainstay microbial culture is time-consuming and constrained by variable growth requirements. In this study, we explored the use of Nanopore sequencing as a supplementary tool to alleviate this diagnostic bottleneck., Methods: We developed a targeted Nanopore method based on amplification of bacterial 16S rRNA gene and fungal internal transcribed spacer region. The performance was compared with routine infectious disease workups on 43 respiratory specimens., Results: Nanopore successfully identified majority of microbes (47/54, 87.04%) and 7 possible pathogens not detected by routine workups, which were attributable to the content of microbiological investigations (n = 5) and negative culture (n = 2). The average sequencing time for first target reads was 7 min (1-43 min) plus 5 h of pre-sequencing preparation., Conclusions: The Nanopore method described here was rapid, economical and hypothesis-free, which might provide valuable hints to further microbiological follow-up for opportunistic pathogens missed or not detectable by conventional tests.

Background: Respiratory infections are a major threat for lung recipients. We aimed to compare with a monocentric study the impact of late viral and bacterial respiratory infections on the graft function., Methods: Patients, who survived 6 months or more following lung transplantation that took place between 2009 and 2014, were classified into three groups: a viral infection group (VIG) (without any respiratory bacteria), a bacterial infection group (BIG) (with or without any respiratory viruses), and a control group (CG) (no documented infection). Chronic lung allograft dysfunction (CLAD) and acute rejection were analysed 6 months after the inclusion in the study., Results: Among 99 included lung recipients, 57 (58%) had at least one positive virological respiratory sample during the study period. Patients were classified as follows: 38 in the VIG, 25 in the BIG (among which 19 co-infections with a virus) and 36 in the CG. The BIG presented a higher initial deterioration in lung function (p = 0.05) than the VIG. But 6 months after the infection, only the VIG presented a median decrease of forced expiratory volume in 1 s; - 35 mL (IQR; - 340; + 80) in the VIG, + 140 mL (+ 60;+ 330) in the BIG and + 10 (- 84;+ 160) in the CG, p < 0.01. Acute rejection was more frequent in the VIG (n = 12 (32%)), than the BIG (n = 6 (24%)) and CG (n = 3 (8%)), p < 0.05, despite presenting no more CLAD (p = 0.21)., Conclusions: Despite a less severe initial presentation, single viral respiratory infections seem to lead to a greater deterioration in lung function, and to more acute rejection, than bacterial infections.

Respiratory infections pose a significant threat to the success of solid organ transplantation, and the diagnosis and management of these infections are challenging. The current narrative review addressed some of these challenges, based on evidence from the literature published in the last 20 years. Specifically, we focused our attention on (i) the obstacles to an etiologic diagnosis of respiratory infections among solid organ transplant recipients, (ii) the management of bacterial respiratory infections in an era characterized by increased antimicrobial resistance, and (iii) the development of antimicrobial stewardship programs dedicated to solid organ transplant recipients., Competing Interests: The authors declare no conflict of interest. The funder had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

There are several convenient and accurate molecular assays to detect respiratory bacterial infection. The NeoPlex RB-8 detection kit (NeoPlex RB-8) is a new multiplex real-time PCR assay that simultaneously detects Streptococcus pneumoniae , Mycoplasma pneumoniae , Chlamydophila pneumoniae , Legionella pneumophila , Haemophilus influenzae , Bordetella pertussis , Bordetella parapertussis , and Moraxella catarrhalis in a single test. This study compared the clinical concordance of NeoPlex RB-8 with another method, Seeplex PneumoBacter ACE detection assay (Seeplex PB ACE), which simultaneously detects S. pneumoniae , M. pneumoniae , C. pneumoniae , L. pneumophila , H. influenzae , and B. pertussis We tested 2,137 nasopharyngeal swab and sputum specimens using both assays. For discordant Bordetella parapertussis and M. catarrhalis specimens, we also performed bidirectional sequencing. For S. pneumoniae , M. pneumoniae , C. pneumoniae , L. pneumophila , H. influenzae , and B. pertussis , which are detected by both NeoPlex RB-8 and Seeplex PB ACE, the positive and negative agreement between the two assays ranged from 91.7 to 100% (κ = 0.918 to 1). S. pneumoniae and H. influenzae were the most discordant targets and measured with higher sensitivity and specificity by NeoPlex RB-8 than Seeplex PB ACE. For Bordetella parapertussis and M. catarrhalis , which are not detected by Seeplex PB ACE, NeoPlex RB-8 sensitivity and specificity were >99%. Overall, NeoPlex RB-8 was highly comparable to Seeplex PB ACE, but NeoPlex RB-8 was more clinically accurate, with higher throughput and more convenience., (Copyright © 2020 American Society for Microbiology.)

Background: Rapid molecular diagnosis of infections has contributed to timely treatments and antimicrobial stewardship. However, the benefit and cost-effectiveness vary in each country or community because they have different standard practices and health care systems. In Japan, rapid antigen tests (RATs) have been frequently used for pediatric respiratory infections. We investigated the impact and cost-effectiveness of a multiplex PCR (mPCR) respiratory panel for pediatric respiratory infections in a Japanese community hospital., Methods: We replaced RATs with an mPCR respiratory panel (FilmArray®) for admitted pediatric respiratory infections on March 26, 2018. We compared the days of antimicrobial therapy (DOT) and length of stay (LOS) during the mPCR period (March 2018 to April 2019) with those of the RAT period (March 2012 to March 2018)., Results: During the RAT and mPCR periods, 1132 and 149 patients were analyzed. The DOT/case was 12.82 vs 8.56 (p < 0.001), and the LOS was 8.18 vs 6.83 days (p = 0.032) in the RAT and mPCR groups, respectively. The total costs during admissions were ∖258,824 ($2331.7) and ∖243,841 ($2196.8)/case, respectively. Pathogen detection rates were 30.2% vs 87.2% (p < 0.001)., Conclusion: Compared to conventional RATs, the mPCR test contributed to a reduction in the DOT and LOS in a Japanese community hospital for admission-requiring pediatric respiratory infections. However, a proper stewardship program is essential to further reduce the unnecessary usage of antimicrobials., (Copyright © 2019 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Background: Acute bacterial sinusitis is a frequent complication of viral upper respiratory infection (URI). We describe the clinical and virologic features of URIs that remain uncomplicated and those that precede an episode of sinusitis. We hypothesize that certain viruses are more likely to lead to acute sinusitis, and we compare viruses identified at the time of diagnosis of sinusitis with those identified early in the URI., Methods: Children aged 48-96 months were followed longitudinally for 1 year. Nasal samples were obtained at surveillance visits, on Day 3-4 of the URI, and on Day 10, when sinusitis was diagnosed. Molecular diagnostic testing was performed on nasal washes for common respiratory viruses and pathogenic bacteria. A standardized score was used to quantify symptom severity., Results: We evaluated 519 URIs, and 37 illnesses in 31 patients met the criteria for sinusitis. Respiratory syncytial virus was detected more frequently in URI visits that led to sinusitis, compared to in uncomplicated URIs (10.8% vs 3.4%; P = .05). New viruses were detected in 29% of sinusitis episodes, and their pattern was different than those patterns observed at surveillance. The median number of URIs per subject per year was 1 (range 0-9) in uncomplicated URI subjects and 3 (range 1-9) in sinusitis subjects (P < .001)., Conclusions: Children who developed sinusitis experienced more frequent URIs, compared to children whose URIs remained uncomplicated. When nasal samples were obtained on the day of diagnosis of acute sinusitis, nearly 30% of children had a new virus identified, suggesting that some children deemed to have sinusitis were experiencing sequential viral infections., (© The Author(s) 2019. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

Background: Adding procalcitonin (PCT) to antibiotic stewardship algorithms may improve antibiotic use. However, PCT protocols need to be adapted to clinical settings and patient populations., Objectives: To review PCT use in different medical settings and patient populations., Sources: Most recent trials and meta-analyses investigating PCT for antibiotic stewardship were reviewed., Content: Several trials found PCT-guided antibiotic stewardship to reduce antibiotic exposure and associated side-effects among patients with respiratory infection and sepsis. Decisions regarding antibiotic use in an individual patient are complex and should be based on the pre-test probability for bacterial infection, the severity of presentation and the results of PCT. In the context of a low pre-test probability for bacterial infections and a low-risk patient, a low PCT level helps to rule out bacterial infection and empiric antibiotic therapy can be avoided. In the context of a high pre-test probability for bacterial infections and/or a high-risk patient with sepsis, monitoring of PCT over time helps to track the resolution of infection and decisions regarding early stop of antibiotic treatment. Although these concepts have been successful in several respiratory infection and sepsis trials, some studies failed to show an added benefit of PCT due to factors such as low protocol adherence and relying on single rather than repeat PCT measurements., Implication: As an adjunct to other clinical and laboratory parameters, PCT provides information about risk for bacterial infection and resolution of infection, and improves antibiotic stewardship decisions, thereby offering more individualized treatment courses with overall reduced antibiotic exposure., (Copyright © 2019 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.)

Background: Distinguishing bacterial and viral respiratory infections is challenging. Novel diagnostics based on differential host gene expression patterns are promising but have not been translated to a clinical platform nor extensively tested. Here, we validate a microarray-derived host response signature and explore performance in microbiology-negative and coinfection cases., Methods: Subjects with acute respiratory illness were enrolled in participating emergency departments. Reference standard was an adjudicated diagnosis of bacterial infection, viral infection, both, or neither. An 87-transcript signature for distinguishing bacterial, viral, and noninfectious illness was measured from peripheral blood using RT-PCR. Performance characteristics were evaluated in subjects with confirmed bacterial, viral, or noninfectious illness. Subjects with bacterial-viral coinfection and microbiologically-negative suspected bacterial infection were also evaluated. Performance was compared to procalcitonin., Findings: 151 subjects with microbiologically confirmed, single-etiology illness were tested, yielding AUROCs 0•85-0•89 for bacterial, viral, and noninfectious illness. Accuracy was similar to procalcitonin (88% vs 83%, p = 0•23) for bacterial vs. non-bacterial infection. Whereas procalcitonin cannot distinguish viral from non-infectious illness, the RT-PCR test had 81% accuracy in making this determination. Bacterial-viral coinfection was subdivided. Among 19 subjects with bacterial superinfection, the RT-PCR test identified 95% as bacterial, compared to 68% with procalcitonin (p = 0•13). Among 12 subjects with bacterial infection superimposed on chronic viral infection, the RT-PCR test identified 83% as bacterial, identical to procalcitonin. 39 subjects had suspected bacterial infection; the RT-PCR test identified bacterial infection more frequently than procalcitonin (82% vs 64%, p = 0•02)., Interpretation: The RT-PCR test offered similar diagnostic performance to procalcitonin in some subgroups but offered better discrimination in others such as viral vs. non-infectious illness and bacterial/viral coinfection. Gene expression-based tests could impact decision-making for acute respiratory illness as well as a growing number of other infectious and non-infectious diseases., (Copyright © 2019. Published by Elsevier B.V.)

Background: The value of procalcitonin (PCT) in the diagnosis of bacterial infections and for determining antibiotic usage among patients with acute exacerbations of chronic obstructive pulmonary disease (AECOPD) is currently unclear. Methods: We systematically reviewed the literature and selected studies that evaluated PCT as a biomarker for predicting bacterial infection and compared PCT-based protocols to determine its application in the initiation or discontinuation of antibiotics. Guidance for systematic reviews from Cochrane and the GRADE were followed to perform this study. Data were pooled and analyzed by using a random-effects or a fixed-effects model based on the heterogeneity. Results: The pooled sensitivity and specificity of PCT in diagnosing respiratory bacterial infections were 0.60 and 0.76, respectively, with the area under the summary receiver operating characteristic curve of 0.77. Subgroup analysis showed that the sensitivity and specificity of PCT for patients in ICU were 0.48 and 0.69, respectively. PCT-based protocols decreased antibiotic prescription (relative risk = 0.66, 95% CI: 0.62-0.71) and total antibiotic exposure (mean difference = -2.60, 95% CI: -4.48-0.72), without affecting clinical outcomes such as treatment failure, length of hospitalization and rates of re-exacerbation or overall mortality. Conclusions: PCT has a moderate ability to distinguish bacterial respiratory infection in patients with AECOPD. PCT-guided algorithm can reduce unnecessary administration of antibiotics without increasing adverse outcomes. However, for patients requiring admission in the ICU, PCT may have a poor diagnostic value, and the PCT-guided algorithm may not effectively and safely reduce the antibiotic exposure.

Objective: To evaluate patients with stable COPD for the presence of potentially pathogenic microorganisms (PPM), systemic inflammation and the effects of short-term antibiotic therapy in PPM positive patients., Methods: From January 2016 to June 2017, we enrolled 96 stable COPD patients. Bacterial cultures from sputum collections were quantitated, along with markers for systemic inflammation including serum C-reactive protein (CRP), interleukin-8 (IL-8) and plasma fibrinogen (FIB) in all patients. All enrolled patients were followed for 12 months. Forty patients were identified as PPM positive and were randomly divided into an antibiotic group and a control group. The antibiotic group was treated with moxifloxacin orally for 6 days. Lung function and markers for systemic inflammation were repeatedly measured at 30 days and 6 months in PPM positive subjects., Results: Binary logistic regression analysis showed that risk factors for PPM positive are bronchiectasis (OR 4.18, 95% CI 1.20-14.59; P =0.025), COPD assessment test (CAT) ≥20 (OR 17.55, 95% CI 2.82-109.18; P =0.002), spontaneous sputum (OR 15.09, 95% CI 1.36-168.02; P =0.027) and sputum purulence (OR 38.43, 95% CI 5.39-274.21; P =0.000). CRP and IL-8 were higher in PPM positive group than those in PPM negative group ( P =0.001, P =0.007, respectively), but there were no differences of FIB between the two groups ( P =0.086). Compared to the PPM negative group, the rate of acute exacerbation of COPD was higher ( P =0.029) and time to next acute exacerbation was shorter ( P =0.030) in PPM positive group. There were no differences in lung function and systemic inflammatory markers either in the control group or the antibiotic group at different time points of follow-up., Conclusion: PPM exists in stable COPD patients and can cause systemic inflammation and is associated with acute exacerbation of COPD. Short-term antibiotic therapy had no effect on systemic inflammation nor on acute exacerbation of COPD. China Clinical Trials Registry: ChiCTR-IOR-15006769., Competing Interests: Jin-Xiang Wang and Hui-Qiao Li are co-first authors for this study. The authors report no conflicts of interest in this work., (© 2019 Wang et al.)

Objective: To analyze the etiologic and epidemiological characteristics of adult acute respiratory infections in Shanghai during 2015-2017. Methods: Data was collected from outpatients with acute respiratory infections who visited the Fever Clinics in three hospitals of different levels in three administrative regions of Shanghai, from 2015 to 2017. Basic information and nasopharyngeal swabs were collected from cases in line with the inclusion criteria. Multiplex RT-PCR and bacterial cultures were performed to detect the respiratory pathogens. Results: A total of 806 individuals were enrolled from 2015 to 2017. Respiratory pathogens were identified in 73.45% (592/806) of the cases, with the virus detection rate as 66.75% (538/806). It was found that the major respiratory pathogens for virus detection were influenza A in 326 (40.45%), influenza B in 116 (14.39%), rhinovirus/enterovirus in 39 (4.84%) of the cases. The overall detection rate of bacteria was 16.13% (130/806), including Klebsiella pneumoniae in 90 (11.17%) cases, Staphylococcus Aureus in 46 (5.71%) cases. Other kind of bacteria were not detected in our study. The detection rates on Mycoplasma pneumoniae was 5.33% (43/806) and on Chlamydia pneumonia was 0.37% (3/806). Co-infection with multiple pathogens was detected in 18.61% (150/806) of the cases, including 135 with double infection (accounting for 90.00%), 14 with triple infection and 1 with quadruple infection (accounted for 9.33% and 0.67%, respectively). Among the 150 cases with co-infections, the main identified pathogens were influenza A, Klebsiella pneumoniae, Staphylococcus aureus, and Mycoplasma pneumoniae. Pathogens of acute respiratory infections that identified among the outpatients from the Fever Clinics at different time, region or population, the characteristics were different ( P <0.001). Conclusions: In 2015-2017, outpatients with acute respiratory infections in Shanghai were mainly caused by influenza virus or other viruses, however dynamically with its composition, time, region and characteristics of the population. It is necessary to strengthen and combine related medical and preventive services and to develop the appropriate strategies regarding clinical diagnosis and treatment.

The prevalence of respiratory viruses in immunocompromised adult patients and the association with clinical outcomes is still underexplored. Our goal was to assess the epidemiology and the potential clinical impact of respiratory viral infections in a high-risk patient population. Two large hospitals performed a respiratory Taqman array card (TAC), targeting 24 viruses, 8 bacteria, and 2 fungi simultaneously, on 435 samples from 397 symptomatic immunocompromised patients. Clinical details were collected retrospectively using a structured case report form. An overall positivity rate of 68% was found (51% mono- and 17% co-infections). Pathogen distribution was as follows: influenza A (20.7%), rhinoviruses (15.2%), coronaviruses (7.8%), Pneumocystis jirovecii (7.4%), RSV (7.1%), and CMV (6.0%) were the most frequently encountered, followed by HSV (5.5%), hMPV (4.4%), parainfluenza viruses (3.9%), influenza B (3.7%), and Aspergillus species (3.7%). Other pathogens were not detected or detected only in ≤ 1% of samples. Hospital and ICU admission rates were 84% and 11%, respectively. The presence of a pathogen was strongly associated with higher need for supplemental oxygen (p = 0.001), but it had no impact on ICU admission, mechanical ventilation requirement, antibacterial therapy, or mortality. In conclusion, our study described the epidemiology of respiratory pathogens in a large group of symptomatic immunocompromised patients and provides evidence of a relationship between pathogen detection and the need for supplemental oxygen. This association was still found after the exclusion of the results positive for influenza viruses, suggesting that non-influenza viruses contribute to severe respiratory illness in patients with compromised immunity.

Background: Cystic fibrosis (CF) is now a recognised entity in India, with prevalence rates between 1/10,000 and 1/50,000. However, no data were available with regard to the profile of respiratory pathogens in the Indian setting., Materials and Methods: The records of respiratory secretion bacterial cultures of children with CF in a tertiary care hospital in North India from January 2010 to December 2016 were reviewed. Culture data were evaluated; the organisms were noted and their antimicrobial susceptibilities were analysed. The microbiological profile and antimicrobial susceptibility pattern of CF patients were evaluated., Results: A total of 445 samples from 146 children were processed, of which 246 (55%) samples showed bacterial growth. Mixed infections 48 (19.5%) were common in older children. Children aged 3-6 months (62.5%) showed the highest culture positivity. The most commonly isolated organisms were Pseudomonas aeruginosa (52.6%) and Staphylococcus aureus. Children with initial cultures positive for P. aeruginosa had 55% of their subsequent cultures showing polymicrobial infections. P. aeruginosa was most susceptible to ciprofloxacin (89%) and piperacillin-tazobactum (88%). Among the staphylococcal isolates, 38% were methicillin-resistant S. aureus (MRSA). The percentage of MRSA increased from 66% in 2010 to 75% in 2012, followed by a decline to 24% in 2016., Conclusions: The pattern of airway colonisation in the Indian setting is different from the Caucasian population, and P. aeruginosa and Burkholderia cepacia complex appear early. Colonisation with P. aeruginosa benefits from therapy. In case of infection, care must be taken while initiating empiric therapy. It should be based on local antibiograms to prevent the emergence of resistant microbes., Competing Interests: None

Appropriate antibiotic treatment for respiratory tract infections (RTIs) necessitates rapid and accurate diagnosis of microbial etiology, which remains challenging despite recent innovations. Several host response-based biomarkers due to infection have been suggested to allow discrimination of bacterial and non-bacterial microbial RTI etiology. This review provides an overview of clinical studies that investigated the diagnostic performance of host-response proteomic biomarkers to identify RTI microbial etiology. Procalcitonin and C-reactive protein have been studied most extensively; whereof procalcitonin has demonstrated the strongest diagnostic performance compared to other biomarkers. Proadrenomedullin, soluble triggering receptor expressed on myeloid cells-1, neopterin and pentraxin-3 need more studies to confirm their diagnostic value. For syndecan-4 and lipocalin-2 currently insufficient evidence exists. Common limitations in several of the studies were the relatively small scale setting, heterogeneous patient population and the absence of statistical power calculation.

Background: Procalcitonin (PCT) is a well-established marker for bacterial infection. Recently the US Food and Drug Administration approved the expanded use of this biomarker to guide clinical decisions for antibiotic treatment in patients with lower respiratory tract infections. Both the Architect BRAHMS PCT (PCT-A) and Vidas BRAHMS PCT (PCT-V) are approved for this indication. The aim of this study is to evaluate analytical performance of PCT-A in comparison to PCT-V., Methods: PCT-A and PCT-V were evaluated for intra- and interassay precision and functional sensitivity. To assess the accuracy of PCT-A, 108 residual plasma specimens were randomly selected from routine hospital orders, and PCT was measured concurrently with PCT-A and PCT-V., Results: Both assays demonstrated excellent precision, with intraassay precision ranging from 2.2% to 4.0% CV and interassay precision ranging from 2.5% to 3.6% CV. The functional sensitivity was verified at 0.01 ng/mL for PCT-A and at 0.05 ng/mL for PCT-V. The Passing-Bablok regression revealed approximately 20% negative bias of PCT-A compared to PCT-V (PCT-A = 0.042 + 0.79 × PCT-V, r = 0.995). The concordance of the 2 methods at diagnostically important cutoffs (0.10, 0.25, 0.50, and 2.0 ng/mL) was excellent, with overall agreement >93% at each threshold., Conclusion: The results of our study show improved sensitivity and equivalent clinical performance of PCT-A compared to PCT-V. The availability of this test on common clinical immunoassay analyzers may help accelerate its adoption into antimicrobial stewardship programs and thereby improve antibiotic use and patient outcomes., (© 2018 American Association for Clinical Chemistry.)

Respiratory tract infections represent a major cause of morbidity and mortality despite the progress made in their diagnosis and treatment. Since the clinical presentation of a viral or bacterial infection is often similar, the identification of a biomarker that could guide the clinician whether or not to introduce an antibiotic therapy is crucial. C-reactive protein and procalcitonin are the most commonly used biomarkers as a diagnostic tool for respiratory tract infections. New biomarkers show promising results for assessing the severity of infection and identifying patients at risk for complications. However, the use of biomarkers has limitations and the diagnosis of a bacterial infection should not be based solely on the measurement of a biomarker., Competing Interests: Les auteurs n’ont déclaré aucun conflit d’intérêts en relation avec cet article.

Background: Respiratory tract infections (RTIs) are the most common illness in children, and rapid diagnosis is required for the optimal management of RTIs, especially severe infections., Methods: Nasopharyngeal swab or sputum specimens were collected from children aged 19 days to 15 years who were admitted to a hospital in Shanghai and diagnosed with RTIs. The specimens were tested with the FilmArray Respiratory Panel, a multiplex PCR assay that detects 16 viruses, Mycoplasma pneumoniae (M. pneumoniae), Bordetella pertussis (B. pertussis) and Chlamydophila pneumoniae (C. pneumoniae)., Results: Among the 775 children studied, 626 (80.8%, 626/775) tested positive for at least one organism, and multiple organisms were detected in 198 (25.5%). Rhinoviruses/enteroviruses (25.5%, 198/775) were detected most often, followed by respiratory syncytial virus (19.5%, 151/775), parainfluenza virus 3 (14.8%, 115/775), influenza A or B (10.9%), adenovirus (10.8%), M. pneumoniae (10.6%) and B. pertussis (6.3%). The prevalence of organisms differed by age, and most of the viruses were more common in winter. Of the 140 children suspected of having pertussis, 35.0% (49/140) tested positive for B. pertussis., Conclusions: FilmArray RP allows the rapid simultaneous detection of a wide number of respiratory organisms, with limited hands-on time, in Chinese pediatric patients with RTIs.

Background: Pleural infection is a common complication of pneumonia associated with high mortality and poor clinical outcome. Treatment of pleural infection relies on the use of broad-spectrum antibiotics because reliable pathogen identification occurs infrequently. We performed a feasibility interventional clinical study assessing the safety and significance of ultrasound (US)-guided pleural biopsy culture to increase microbiological yield. In an exploratory investigation, the 16S ribosomal RNA technique was applied to assess its utility on increasing speed and accuracy vs standard microbiological diagnosis., Methods: Twenty patients with clinically established pleural infection were recruited. Participants underwent a detailed US scan and US-guided pleural biopsies before chest drain insertion, alongside standard clinical management. Pleural biopsies and routine clinical samples (pleural fluid and blood) were submitted for microbiological analysis., Results: US-guided pleural biopsies were safe with no adverse events. US-guided pleural biopsies increased microbiological yield by 25% in addition to pleural fluid and blood samples. The technique provided a substantially higher microbiological yield compared with pleural fluid and blood culture samples (45% compared with 20% and 10%, respectively). The 16S ribosomal RNA technique was successfully applied to pleural biopsy samples, demonstrating high sensitivity (93%) and specificity (89.5%)., Conclusions: Our findings demonstrate the safety of US-guided pleural biopsies in patients with pleural infection and a substantial increase in microbiological diagnosis, suggesting potential niche of infection in this disease. Quantitative polymerase chain reaction primer assessment of pleural fluid and biopsy appears to have excellent sensitivity and specificity., (Copyright © 2018 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)

Background: The emergence and spread of antibiotic resistant micro-organisms is a global concern, which is largely attributable to inaccurate prescribing of antibiotics to patients presenting with non-bacterial infections. The use of 'omics' technologies for discovery of novel infection related biomarkers combined with novel treatment algorithms offers possibilities for rapidly distinguishing between bacterial and viral infections. This distinction can be particularly important for patients suffering from lower respiratory tract infections (LRTI) and/or sepsis as they represent a significant burden to healthcare systems. Here we present the study details of the TAILORED-Treatment study, an observational, prospective, multi-centre study aiming to generate a multi-parametric model, combining host and pathogen data, for distinguishing between bacterial and viral aetiologies in children and adults with LRTI and/or sepsis., Methods: A total number of 1200 paediatric and adult patients aged 1 month and older with LRTI and/or sepsis or a non-infectious disease are recruited from Emergency Departments and hospital wards of seven Dutch and Israeli medical centres. A panel of three experienced physicians adjudicate a reference standard diagnosis for all patients (i.e., bacterial or viral infection) using all available clinical and laboratory information, including a 28-day follow-up assessment. Nasal swabs and blood samples are collected for multi-omics investigations including host RNA and protein biomarkers, nasal microbiota profiling, host genomic profiling and bacterial proteomics. Simplified data is entered into a custom-built database in order to develop a multi-parametric model and diagnostic tools for differentiating between bacterial and viral infections. The predictions from the model will be compared with the consensus diagnosis in order to determine its accuracy., Discussion: The TAILORED-Treatment study will provide new insights into the interplay between the host and micro-organisms. New host- or pathogen-related biomarkers will be used to generate a multi-parametric model for distinguishing between bacterial and viral infections. This model will be helpful to better guide antimicrobial therapy for patients with LRTI and sepsis. This study has the potential to improve patient care, reduce unnecessary antibiotic prescribing and will contribute positively to institutional, national and international healthcare economics., Trial Registration: NCT02025699 . Registration Date: January, 1, 2014.

Purpose: Preoperative airway colonization is associated with increased risk of postoperative respiratory complications following lung resection. This study compares the rates of preoperative lower respiratory tract colonization identified by traditional culture and novel 16S polymerase chain reaction (PCR) tests., Materials and Methods: Preoperative sputum and bronchoalveolar lavage (BAL) samples for 49 lung resection patients underwent culture and 16S PCR analyses. Rates of positive test results were determined and relationships between test results and suspected postoperative respiratory tract infection and hospital length of stay (LOS) were investigated., Results: Preoperative BAL cultures were positive for 29 (59.2%) patients (population estimate 95%CI 45.2%-71.8%). 16S PCR tests were positive for 28 (57.1%) patients (population estimate 95%CI 43.3%-70.0%). 17 (34.7%) patients suffered suspected postoperative respiratory tract infection (population estimate 95%CI 22.9%-48.7%). Positive 16S PCR results tended to be associated with longer LOS (median 7.5 days vs 4.0 days for negative, p = 0.08) and increased risk of suspected postoperative respiratory tract infection (46.4% for positive vs 19.0% for negative, p = 0.07)., Conclusions: Rates of colonization identified by culture and 16S PCR analyses of BAL samples were similar. Future research should attempt to clarify associations between airway colonization identified by 16S PCR and outcomes. 16S PCR may be useful when stratifying risk of postoperative respiratory complications., (Copyright © 2018 Elsevier Inc. All rights reserved.)