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SN comprehensive clinical medicine 2(12), 2540-2545 (2020). doi:10.1007/s42399-020-00597-2 special issue: "Topical Collection on COVID-19", Published by Springer International Publishing, [Cham]

The LAMP-based eazyplex® BloodScreen GN was evaluated for the detection of frequent Gram-negatives directly from positive blood culture (BC) bottles. A total of 449 BCs were analyzed. Sensitivities and specificities were 100% and 100% for Escherichia coli, 95.7% and 100% for Klebsiella pneumoniae, 100% and 100% for blaCTX-M, 100% and 100% for Klebsiella oxytoca, 100% and 99% for Proteus mirabilis, and 100% and 99.8% for Pseudomonas aeruginosa, respectively. The time to result ranged from 8 to 16 min, plus about 6 min for sample preparation. The eazyplex® BloodScreen GN is a reliable molecular assay for rapid BC testing.

Coronavirus-specific antibodies decline fast and allow reinfection starting 6 months post infection. Knowledge on reinfection is very important for SARS-CoV-2. Here we report a reinfection with SARS-CoV-2 of a 23 years old female health care worker 177 days after the onset of the first episode. The second episode was clinically more severe as the first episode. Our data show that reinfection with SARS-CoV-2 can occur with increased clinical impact in immunocompetent, young individuals after less than half a year.

Time to positivity (TTP) is the delay of time from incubation to blood culture positivity. Short TTP can predict mortality and source of infection. The aim of this study was to investigate the value of TTP of patients with bloodstream infections with enterococci (E-BSI).In a single centre retrospective cohort study in Germany, the data of 244 patients with monomicrobial E-BSI were analyzed with hospital mortality as the primary outcome of interest from January 1 2014 to December 31 2016. Mortality rate of patients with bloodstream infections (BSI) with E. faecalis was 16.7%, Vancomycin sensitive E. faecium (VSEfm) 26.7% and Vancomycin resistant E. faecium (VREfm) 38.2%. Cut-offs showed a significantly higher mortality rate when compared to longer TTP (E. faecalis: P=0.047; VSEfm: P=0.02), but were not risk factors in survival analysis (E.faecalis: HR (hazard ratio): 2.73; P=0.17; VSEfm: HR: 1.63; P=0.15; VREfm: HR: 1.24; P=0.63). TTP≤10.5 hours with E. faecalis BSI was a discriminator for cardiovascular source of infection (AUC: 0.75). A short TTP could predict mortality rates and source of infection but was not an independent parameter for risk of death in survival analysis.

The aim of this study was to evaluate the diagnostic accuracy and the clinical impact of isothermal loop-mediated amplification (LAMP; eazyplex® MRSA kits) for rapid diagnosis of Staphylococcus aureus bacteremia (SAB) in comparison with conventional blood culture diagnostics. We performed a retrospective, single-center observational study over the period between November 2016 and December 2018 on patients (and blood cultures) with growth of Gram-positive cocci in clusters in their blood cultures. We quantified diagnostic accuracy with sensitivity and specificity for detection of S. aureus, methicillin-resistant S. aureus (MRSA), and the mecA/C resistance genes in 797 blood cultures. The clinical impact was assessed by time to result reporting, time to appropriate treatment, and length of stay in intensive care unit (ICU) in 190 SAB patients. We observed sensitivity and specificity above 90% for S. aureus detection (sensitivity (95% confidence interval (CI)), 99.57% (97.61%, 99.98%); specificity, 99.12% (97.95%, 99.71%)), for MRSA detection (sensitivity, 100% (89.11%, 100.00%); specificity, 99.72% (99.05, 99.96)), and for mecA/C detection (sensitivity, 94.71% (91.85%, 96.78%); specificity, 95.89% (93.58%, 97.54%)). LAMP testing was associated with shorter median time to result reporting (24.0 h (first and third quartiles (Q1–Q3), 20.0–27.0 h) vs 41.5 h (36.0–46.0 h); p

Small-colony variants are slow-growing subpopulations of bacteria known to be involved in latent or recurrent infections, especially in deep-seated foci. Their atypical growth in small colonies can hamper prompt and correct identification in clinical specimens. Here, we present the first case of multiple spinal abscesses and spondylodiscitis associated with an Enterococcus faecium small-colony-variant in an immunocompetent patient. This case demonstrates the diagnostic challenges when encountering this phenotype in the diagnostic laboratory.

In dieser zum nun abgesagten Internistenkongress 2020 geplanten MMW-Ausgabe legen wir den Schwerpunkt — wie konnte es anders sein — auf die Infektiologie.

The prevalence of infections with enterococci is increasing worldwide. However, little is known about the mechanisms which enable these opportunistic pathogens to cause infections of their host. Here we demonstrate that Enterococcus faecium in the presence of lysozyme induces necrosis in human and mouse cells after 4 h indicated by disrupted cellular membranes of epithelial (HeLa), myeloid (U937, J774A.1) and lymphoid (Jurkat J16, thymocytes), but not intestinal epithelial cells (CaCo-2, CMT-93). Using an appropriate mutant strain it was shown that the enterococcal surface-protein SgrA is involved in cell death induction in mouse cells (J774A.1, thymocytes). Microscopic analyses of epithelial cells 30 min post infection revealed that lysozyme increases adhesion of E. faecium to HeLa, but not CaCo-2 cells. At that time the phalloidin-FITC-stained cytoskeleton of infected cells was still intact, whereas 2 h post infection the F-actin network of HeLa, but not CaCo-2 cells was disrupted. Hence, the early, lysozyme-mediated increase of bacterial adherence plays an important role for cell death induction by E. faecium in HeLa cells. Moreover, bacterial extracellular hydrogen peroxide might contribute to necrosis induction, since the rate of propidium iodide-positive HeLa and J774A.1 cells was lowered after infection with a ROS-deficient E. faecium mutant.

We describe the first isolation of Mycobacterium hassiacum, a rapid-growing, partial acid-resistant mycobacterium, in a respiratory specimen from a patient with exacerbated chronic obstructive pulmonary disease. To provide therapeutic recommendation for future cases, antibiotic susceptibility testing of 3 clinical isolates was performed by broth microdilution. All strains tested showed susceptibility to clarithromycin, imipenem, ciprofloxacin, and doxycycline. The role of M hassiacum as a respiratory pathogen remains unclear and needs to be evaluated by future reports.