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Purpose: Blood culture (BC) is the gold standard for diagnosing blood stream infections (BSI) but is limited by long turnaround times (TAT) and low detection rate. The T2 Magnetic Resonance method (T2MR) offers a rapid, culture-independent alternative. The objective of this study was to compare the performance of the T2Bacteria assay to BCs in a real-world setting. Methods: Retrospective comparative study consisting of T2Bacteria samples and BCs sampled within 72 h from the T2Bacteria sample. The primary outcome was detections by BC and T2Bacteria, respectively. The secondary outcome was difference in TAT. Results: In total, 640 episodes were included, consisting of 640 T2Bacteria samples and 2,117 BCs. A median of three BCs was collected for each T2Bacteria sample. Overall positivity was 101 (15.8%) by either method. In 29 (28.7%) episodes, both T2Bacteria and BC were concordantly positive. In discordant episodes, 46/101 (45.5%) episodes were T2Bacteria positive/BC negative and 26/101 (25.7%) were T2Bacteria negative/BC positive (McNemar χ2, p < 0,05). In T2Bacteria positive/BC negative episodes, eight had growth of the same microorganism in a non-BC culture. Median (IQR) TAT for BC was 35 h and 30 min (25 h 50 min − 45 h 24 min), compared to 21 h and 3 min (17 h 6 min − 27 h 30 m) for T2Bacteria (p < 0.001), with longer delays for samplings occurring outside work hours. Conclusions: The study highlights a high discordance between T2Bacteria and BC and suggests complementary roles of the methods in BSI diagnostics. Furthermore, it is crucial to improve TAT by reducing preanalytical delays. [ABSTRACT FROM AUTHOR]

Background: Sepsis is associated with substantial mortality rates. Antibiotic treatment is crucial, but global antibiotic resistance is now classified as one of the top ten global public health risks facing humanity. Ozone (O3) is an inorganic molecule with no evident function in the body. We investigated the bactericide properties of ozone, using a novel system of extracorporeal ozone blood treatment. We hypothesized that ozone would decrease the concentration of viable Escherichia coli (E. coli) in human whole blood and that the system would be technically feasible and physiologically tolerable in a clinically relevant model of E. coli sepsis in swine. Methods: The E. coli strain B09-11822, a clinical isolate from a patient with septic shock was used. The in vitro study treated E. coli infected human whole blood (n = 6) with ozone. The in vivo 3.5-h sepsis model randomized swine to E. coli infusion and ozone treatment (n = 5) or E. coli infusion and no ozone treatment (n = 5). Live E. coli, 5 × 107 colony-forming units (CFU/mL) was infused in a peripheral vein. Ozone treatment was initiated with a duration of 30 min after 1.5 h. Results: The single pass in vitro treatment decreased E. coli by 27%, mean 1941 to 1422 CFU/mL, mean of differences − 519.0 (95% CI − 955.0 to − 82.98, P = 0.0281). pO2 increased (95% CI 31.35 to 48.80, P = 0.0007), pCO2 decreased (95% CI − 3.203 to − 1.134, P = 0.0069), oxyhemoglobin increased (95% CI 1.010 to 3.669, P = 0.0113). Methemoglobin was not affected. In the sepsis model, 9/10 swine survived. One swine randomized to ozone treatment died from septic shock before initiation of the treatment. Circulatory, respiratory, and metabolic parameters were not affected by the ozone treatment. E. coli in arterial blood, in organs and in aerobic and anaerobic blood cultures did not differ. Hemoglobin, leucocytes, and methemoglobin were not affected by the treatment. Conclusions: Ozone decreased the concentration of viable E. coli in human whole blood. The system was technically feasible and physiologically tolerable in porcine sepsis/septic shock and should be considered for further studies towards clinical applications. [ABSTRACT FROM AUTHOR]

Rapid identification and antimicrobial susceptibility testing remain a crucial step for early efficient therapy of bloodstream infections. Traditional methods require turnaround times of at least 2 days, while rapid procedures are often associated with extended hands-on time. The Accelerate Pheno™ System provides microbial identification results within 90 min and susceptibility data in approximately 7 h directly from positive blood cultures with only few minutes of hands-on time. The aim of this study was, therefore, to evaluate the performance of the Accelerate Pheno™ System in identification and antimicrobial susceptibility testing of both Gram-positive and Gram-negative bacteria directly from clinical blood culture samples. We analyzed 108 and 67 blood culture bottles using the Accelerate PhenoTest™ BC kit with software version v1.0 and the FDA-cleared version v1.2, respectively. Reliable identification was achieved for Enterobacteriaceae, staphylococci, and enterococci, with 76/80 (95%), 42/46 (91%), and 10/11 (91%) correct identifications. Limitations were observed in the identification of streptococci, including Streptococcus pneumoniae and Streptococcus pyogenes, and coagulase-negative staphylococci. Antimicrobial susceptibility results for Enterobacteriaceae, for amikacin, ertapenem, ciprofloxacin, gentamicin, meropenem, and piperacillin-tazobactam ranged between 86 and 100% categorical agreement. Using v1.2, results for ceftazidime showed 100% concordance with the reference method. For staphylococci, the overall performance reached 92% using v1.2. Qualitative tests for detection of methicillin or macrolide-lincosamide-streptogramin B (MLSB) resistance caused major and very major errors for isolates. Overall, the present data show that the Accelerate Pheno™ system can, in combination with Gram stain, be used as a rapid complementation to standard microbial diagnosis of bloodstream infections. [ABSTRACT FROM AUTHOR]

There are several approaches available for purifying microorganisms prior to matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) analysis. In the present study, rapid BACpro® II (Nittobo Medical Co., Ltd., Tokyo, Japan), a new application, has been compared with Sepsityper® kit (Bruker Daltonics, Billerica, USA) and an in-house method. Samples were also tested with two modules, standard and Sepsityper®, identified in the Bruker MALDI-TOF MS. The bottles having monomicrobial growth were included in the study according to Gram staining results. In total, two hundred blood culture bottles were included but there was no growth in one of the subcultures so 199 blood culture bottles were studied prospectively. With the standard MALDI-TOF MS analysis, rapid BACpro® II could successfully identify microorganisms in 174/199 (87.4%) of the bottles where Sepsityper® kit and in-house method were successful in 136/199 (68.3%) and 114/199 (57.3%), respectively. When the MALDI-TOF MS data were analysed by Sepsityper® module, the identification rates were increased to 94.4%, 82.1% and 69.8% (p < 0.001), respectively. In the Sepsityper® module, 72/73 (98.6%) of Gram-negative and 97/106 (91.5%) of Gram-positive microorganisms were detected by rapid BACpro® II method. The present study shows that rapid BACpro® II is a reliable preparation procedure and has higher rates of identification compared with Sepsityper® kit and in-house method. The use of the Sepsityper® module in blood cultures increases the chance of identification for all three methods studied. [ABSTRACT FROM AUTHOR]

Cystic fibrosis (CF) patients become colonized by pathogenic bacteria as well as by Candida species. The interplay between different microorganisms may play a key role in the prognosis of CF. The aim of the study was to analyze the coexistence patterns of bacteria and Candida spp. in sputum samples of patients with CF and to compare these patterns with the results of patients with other respiratory disorders (ORD). Sputum samples from 130 patients with CF and 186 patients with ORD were cultured on six different agar plates promoting the growth of bacteria and yeasts. Bacterial and Candida species were identified with MALDI-TOF MS. Pathogenic bacteria were found in 69.2% of the sputum samples of the CF patients, and in 44.1% the patients with ORD. CF patients tended to have growth of Pseudomonas aeruginosa and Staphylococcus aureus in sputum more often than patients with ORD. Overall, there was no difference in the coexistence of pathogenic bacteria and Candida spp. in these patient groups. However, when analyzed at the species level, P. aeruginosa and S. aureus coexisted with Candida spp. more frequently in sputum samples of CF patients compared with patients with ORD. Also, when analyzed according to age, it was shown that the adult (≥ 18 years) CF patients had a higher rate of coexistence of any pathogenic bacteria and Candida spp. than the children with CF and the adult patients with ORD. The rate for colonization with Candida together with pathogenic bacteria is increased in adult patients with CF. [ABSTRACT FROM AUTHOR]

Knowledge of infective endocarditis (IE) caused by Streptococcus dysgalactiae (SD) is limited. This study aimed to identify the clinical and microbiological features of SD-caused IE and to investigate any possible synergy between penicillin and gentamicin on SD isolates. Cases of IE 2008-2016 due to SD reported to the Swedish Registry of Infective Endocarditis (SRIE) were identified. Isolates were emm typed and synergy between antibiotics was determined in time-kill experiments. Medical records were reviewed and SD-cases were compared to cases of IE due to other pathogens reported to the SRIE. Fifty cases of SD-caused IE were confirmed. emm types stC74a, stG62647, and stG643 were most commonly encountered. The patients had a median age of 74 years (range 38-93) and were significantly older compared to patients with Staphylococcus aureus-caused IE, (65 years (p = 0.003)). The median time to diagnosis from symptom onset was 1 day for patients with SD-caused IE which was less compared to patients with IE due to the other pathogens (2-15 days). Embolization was seen in 46% and the in-hospital mortality was 8%. Etest-based methods did not indicate any synergy between penicillin and gentamicin whereas synergy was noted for four out of nine isolates applying time-kill assays. This is the largest study of SD-caused IE, a condition with an acute onset predominantly affecting elderly people. Synergy between penicillin and gentamicin against some SD isolates was distinguished but the potential benefit of this must be weighed against the risk of aminoglycoside side effects. [ABSTRACT FROM AUTHOR]

Cancer patients with advanced disease display signs of immune suppression, which constitute a major obstacle for effective immunotherapy. Both T cells and NK cells are affected by a multitude of mechanisms of which the generation of reactive oxygen species is of major importance. Therefore, we hypothesized that two weeks of high-dose treatment with the anti-oxidant vitamin E may enhance NK cell function in cancer patients by protecting from oxidative stress. Seven patients with colorectal cancer (Dukes stage C and D) received a daily dose of 750 mg of vitamin E during a period of two weeks and the function, phenotype and receptor expression of NK cells were analyzed. The short-term vitamin E treatment significantly improved NK cell cytolytic activity in six out of the seven patients analyzed. The increased NK cell activity in patients’ PBMC was not due to increased numbers of NK cells or an increase in the proportion of the CD56dim NK cell subpopulation. Furthermore, neither an increased perforin expression nor an enhanced ability of NK cells to produce IFN-γ was observed as a result of vitamin E treatment. Finally, vitamin E treatment was associated with a minor, but consistent, induction of NKG2D expression in all patients analyzed. In conclusion, this pilot study demonstrates that vitamin E may boost NK cell function in patients with colorectal cancer. Further studies are warranted to explore the potential of vitamin E as an adjuvant for immunotherapy against cancer and to determine the underlying mechanism(s) behind vitamin E induced NK cell activation. [ABSTRACT FROM AUTHOR]