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Campylobacteriosis is an infectious gastrointestinal disease caused by Campylobacter spp. In most cases, it is either underdiagnosed or underreported due to poor diagnostics and limited databases. Several DNA-based molecular diagnostic techniques, including 16S ribosomal RNA (rRNA) sequence typing, have been widely used in the species identification of Campylobacter. Nevertheless, these assays are time-consuming and require a high quality of bacterial DNA. Matrixassisted laser desorption ionization (MALDI) timeof- flight (TOF) MS is an emerging diagnostic technology that can provide the rapid identification of microorganisms by using their intact cells without extraction or purification. In this study, we analyzed 24 American Type Culture Collection reference isolates of 16 Campylobacter spp. and five unknown clinical bacterial isolates for rapid identification utilizing two commercially available MADI-TOF MS platforms, namely the bioMérieux VITEK® MS and Bruker Biotyper systems. In addition, 16S rRNA sequencing was performed to confirm the species-level identification of the unknown clinical isolates. Both MALDI-TOF MS systems identified the isolates of C. jejuni, C. coli, C. lari, and C. fetus. The results of this study suggest that the MALDI-TOF MS technique can be used in the identification of Campylobacter spp. of public health importance. [ABSTRACT FROM AUTHOR]

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) escape from combination monoclonal antibody treatment is rarely reported. We describe an immunocompromised individual with human immunodeficiency virus and persistent SARS-CoV-2 infection in whom substantial SARS-CoV-2 evolution occurred, including the emergence of 2 mutations associated with escape from the monoclonal antibody cocktail received. [ABSTRACT FROM AUTHOR]

Mpox (monkeypox) represents a diagnostic challenge due to varied clinical presentations and multiple mimics. A commercially available multiplex polymerase chain reaction panel accurately detects mpox virus as well as common mimics (herpes simplex virus, varicella zoster virus) in clinical specimens and could be used in routine clinical, surveillance, and outbreak settings. [ABSTRACT FROM AUTHOR]

Among 283 symptomatic healthcare personnel (HCP) tested for SARS-CoV-2, 51 (18%) were positive. Among those 51 HCP, self reported loss of smell and taste were present in 51% and 52.9%, respectively, with either present in 60.8%. These symptoms had high specificity (93% each, 96% for either) for a positive SARS-CoV-2 test. [ABSTRACT FROM AUTHOR]

Background. Although isoniazid-resistant tuberculosis is more common than multidrug-resistant tuberculosis, it has been much less studied. We examined the impact of isoniazid resistance and treatment regimen, including use of a fluoroquinolone, on clinical outcomes. Methods. A retrospective cohort study among patients with sputum culture-positive tuberculosis was performed. Early fluoroquinolone (FQ) use was defined as receiving ≥5 doses during the first month of treatment. The primary outcome was time to sputum culture conversion (tSCC). A multivariate proportional hazards model was used to determine the association of isoniazid resistance with tSCC. Results. Among 236 patients with pulmonary tuberculosis, 59 (25%) had isoniazid resistance. The median tSCC was similar for isoniazid-resistant and -susceptible cases (35 vs 29 days; P = .39), and isoniazid resistance was not associated with tSCC in multivariate analysis (adjusted hazard ratio = 0.83; 95% confidence interval [CI], .59-1.17). Early FQ use was higher in isoniazid-resistant than -susceptible cases (20% vs 10%; P = .05); however, it was not significantly associated with tSCC in univariate analysis (hazard ratio = 1.48; 95% CI, .95-2.28). Patients with isoniazid-resistant tuberculosis were treated with regimens containing rifampin, pyrazinamide, and ethambutol +/- a FQ for a median of 9.7 months. Overall, 191 (83%) patients were cured. There was no difference in initial treatment outcomes; however, all cases of acquired-drug resistance (n = 1) and recurrence (n = 3) occurred among patients with isoniazid-resistant tuberculosis. Conclusions. There was no significant association with isoniazid resistance and tSCC or initial treatment outcomes. Although patients with isoniazid-resistant tuberculosis had a high cure rate, the cases of recurrence and acquired drug resistance are concerning and highlight the need for longer-term follow-up studies. [ABSTRACT FROM AUTHOR]

Background. The Xpert MTB/RIF (Xpert) assay is a rapid nucleic acid amplification test widely used in settings of high tuberculosis prevalence to detect tuberculosis as well as rpoB mutations associated with rifampin resistance. Data are needed on the diagnostic performance of Xpert in lower-prevalence settings to inform appropriate use for both tuberculosis detection and the need for respiratory isolation. Methods. Xpert was compared to 2 sputum samples, each evaluated with acid-fast bacilli (AFB) smear and mycobacterial culture using liquid and solid culture media, from participants with suspected pulmonary tuberculosis from the United States, Brazil, and South Africa. Results. Of 992 participants enrolled with evaluable results, 22% had culture-confirmed tuberculosis. In 638 (64%) US participants, 1 Xpert result demonstrated sensitivity of 85.2% (96.7% in participants with AFB smear-positive [AFB+] sputum, 59.3% with AFB smear-negative [AFB-] sputum), specificity of 99.2%, negative predictive value (NPV) of 97.6%, and positive predictive value of 94.9%. Results did not differ between higher- and low-prevalence settings. A second Xpert assay increased overall sensitivity to 91.1% (100% if AFB+, 71.4% if AFB-), with specificity of 98.9%. In US participants, a single negative Xpert result predicted the absence of AFB+/culture-positive tuberculosis with an NPV of 99.7%; NPV of 2 Xpert assays was 100%, suggesting a role in removing patients from airborne infection isolation. Xpert detected tuberculosis DNA and mutations associated with rifampin resistance in 5 of 7 participants with rifampin-resistant, culture-positive tuberculosis. Specificity for rifampin resistance was 99.5% and NPV was 98.9%. Conclusions. In the United States, Xpert testing performed comparably to 2 higher-tuberculosis-prevalence settings. These data support the use of Xpert in the initial evaluation of tuberculosis suspects and in algorithms assessing need for respiratory isolation. [ABSTRACT FROM AUTHOR]

Objectives Nosocomial pathogens such as Acinetobacter baumannii are a growing public health threat, due in part to their increasing resistance to antibiotics. Since some strains are resistant to all available antibiotics, novel therapies are urgently needed. Plasmablasts are short-lived B cells found in the blood that can be collected and harnessed to produce therapeutic antibodies. We set out to determine whether plasmablasts are induced during infection with A. baumannii and other nosocomial pathogens. Methods We obtained blood samples from patients infected with antibiotic-resistant nosocomial pathogens, and analysed their plasmablast response by flow cytometry. Results We observed a strong induction of plasmablasts in patients with antibiotic-resistant A. baumannii infection. Furthermore, plasmablasts were also induced in response to other drug-resistant nosocomial pathogens. Conclusions These data suggest that plasmablasts may be broadly harnessed to develop therapeutic antibodies to combat otherwise untreatable antibiotic-resistant infections. [ABSTRACT FROM PUBLISHER]

Background. Whether community-associated methicillin-resistant Staphylococcus aureus (MRSA) genotypes (e.g., USA300) are a major cause of bloodstream infections (BSIs) and health care-associated infections has been poorly defined. Methods. Consecutive MRSA isolates recovered from patients with BSIs were prospectively collected at an urban public hospital. Molecular typing studies were performed. Prevalence and risk factors for the MRSA USA300 genotype were assessed. Results. One hundred thirty-two cases of MRSA BSI were documented over 7.5 months in 2004 (incidence, 6.79 per 1000 admissions); 116 isolates were available for genotyping. Characteristics of the 116 evaluable cases included: a mean age 47 years; 62% were male, 82% were African American, and 22% were HIV seropositive. The crude in-hospital mortality rate was 22%. In 107 cases (92%), there was contact with a health care facility within the year prior to infection, and a nosocomial infection (defined as positive blood culture results obtained >48 h after admission) occurred in 49 cases (42%). PFGE demonstrated that 39 (34%) of the 116 isolates were the MRSA USA300 genotype; 34 (29%) were USA100; 42 (36%) were USA500; and 1 (1%) was USA800. MRSA USA300 accounted for 28% of health care-associated BSIs and 20% of nosocomial MRSA BSIs. In multivariate analysis, isolation of the USA300 genotype was associated with injectiondrug use (OR, 3.67; 95% CI, 1.10–12.28) and skin and soft tissue infection (OR, 4.26; 95% CI, 1.08–16.84). Patients who resided in long-term care facilities (OR, 0.09; 95% CI, 0.01–0.82) and those who were treated with antimicrobials in the prior year were less likely to have MRSA USA300 genotype recovered (OR, 0.10; 95% CI, 0.02–0.49). Conclusions. MRSA USA300 genotype, the predominant cause of community-associated MRSA infections in our area (Atlanta, GA), has now emerged as a significant cause of health care-associated and nosocomial BSI. MRSA USA300 as a nosocomial pathogen presents new challenges to infection control programs. [ABSTRACT FROM AUTHOR]

Background Antiretroviral therapy (ART) for persons with HIV infection prevents tuberculosis (TB) disease. Additionally, sequential ART after initiation of TB treatment improves outcomes. We examined ART use, retention in care, and viral suppression (VS) before, during, and 3 years following TB treatment for an inner-city cohort in the United States. Methods Retrospective cohort study among persons treated for culture-confirmed TB between 2008 and 2015 at an inner-city hospital. Results Among 274 persons with culture-confirmed TB, 96 (35%) had HIV co-infection, including 23 (24%) new HIV diagnoses and 73 (76%) previous diagnoses. Among those with known HIV prior to TB, the median time of known HIV was 6 years, and only 10 (14%) were on ART at the time of TB diagnosis. The median CD4 at TB diagnosis was 87 cells/uL. Seventy-four (81%) patients received ART during treatment for TB, and 47 (52%) has VS at the end of TB treatment. Only 32% of patients had continuous VS 3 years after completing TB treatment. There were 3 TB recurrences and 3 deaths post–TB treatment; none of these patients had retention or VS after TB treatment. Conclusions Among persons with active TB co-infected with HIV, we found that the majority had known HIV and were not on ART prior to TB diagnosis, and retention in care and VS post–TB treatment were very low. Strengthening the HIV care continuum is needed to improve HIV outcomes and further reduce rates of active TB/HIV co-infection in our and similar settings. [ABSTRACT FROM AUTHOR]