Despite being implicated in a wide spectrum of community- and healthcare-acquired infections, anaerobes have not yet been incorporated into systematic surveillance programs in Europe. We conducted a multicentre retrospective observational study analysing all anaerobic strains isolated from blood cultures in 44 European Hospital Centres over a 4-y period (2020-2023). Diagnostic approach, epidemiology, and antimicrobial susceptibility according to EUCAST v. 15.0 were investigated. Our study included 14,527 anaerobes, most of which were Gram-positive (45%) or Gram-negative (40%) bacilli. MALDI-TOF coupled to mass spectrometry was the most widely used tool for species identification (98%). Antimicrobial susceptibility testing was performed in the vast majority of centres, using mostly gradient diffusion strip (77%) and disk diffusion (45%) methods according to EUCAST guidelines. The most prevalent species were Cutibacterium acnes (18.7%), Bacteroides fragilis (16.3%), Clostridium perfringens (5.3%), Bacteroides thetaiotaomicron (4.2%), Fusobacterium nucleatum (3.5%), and Parvimonas micra (3.4%). C. acnes showed high resistance to benzylpenicillin (18%), clindamycin (39%), and imipenem (19% and 13% by MIC methods and disk diffusion, respectively). B. fragilis showed high resistance to amoxicillin/clavulanate (24%), piperacillin/tazobactam (22% and 14% by MIC methods and disk diffusion, respectively), clindamycin (22% by both MIC methods and disk diffusion), meropenem (13%), and metronidazole (10%, only by disk diffusion). A similar resistance pattern was observed in B. thetaiotaomicron, Bacteroides ovatus, and Parabacteroides distasonis. C. perfringens showed high resistance to clindamycin (69% and 45% by MIC methods and disk diffusion, respectively), while benzylpenicillin and metronidazole maintained over 90% activity. F. nucleatum showed high resistance to benzylpenicillin (11%), while Fusobacterium necrophorum showed alarming rates of resistance to clindamycin (12%), meropenem (16%) and metronidazole (11%). This study presented an up-to-date analysis of the diagnostics and epidemiology of anaerobic bacteria in Europe, providing insights for future comparative analyses and the development of antimicrobial diagnostic and management strategies, as well as the optimization of current antibiotic treatments.

(1) Background: Automated blood culture headspace analysis for the detection of volatile organic compounds of microbial origin (mVOC) could be a non-invasive method for bedside rapid pathogen identification. We investigated whether analyzing the gaseous headspace of blood culture (BC) bottles through gas chromatography-ion mobility spectrometry (GC-IMS) enables differentiation of infected and non-infected; (2) Methods: BC were gained out of a rabbit model, with sepsis induced by intravenous administration of E. coli (EC group; n = 6) and control group (n = 6) receiving sterile LB medium intravenously. After 10 h, a pair of blood cultures was obtained and incubated for 36 h. The headspace from aerobic and anaerobic BC was sampled every two hours using an autosampler and analyzed using a GC-IMS device. MALDI-TOF MS was performed to confirm or exclude microbial growth in BCs; (3) Results: Signal intensities (SI) of 113 mVOC peak regions were statistically analyzed. In 24 regions, the SI trends differed between the groups and were considered to be useful for differentiation. The principal component analysis showed differentiation between EC and control group after 6 h, with 62.2% of the data variance described by the principal components 1 and 2. Single peak regions, for example peak region P_15, show significant SI differences after 6 h in the anaerobic environment (p < 0.001) and after 8 h in the aerobic environment (p < 0.001); (4) Conclusions: The results are promising and warrant further evaluation in studies with an extended microbial panel and indications concerning its transferability to human samples.

Candidemia is rare and has a high mortality rate. This study analyses the impact of bedside antifungal stewardship (AFS) on clinical management and prognosis of patients with candidemia at a university hospital in Germany. All patients with at least one positive blood culture with Candida species between 2014 and 2016 received bedside AFS with standardized recommendations. Medical records were retrospectively analyzed. Results from the intervention period from 2014-2016 (n=109), with focus on 2016 (n=39), were compared with those from the pre-intervention period in 2013 (n=30). Bedside AFS was performed in 24/35 (69%) surviving patients in 2016 within the first 3 days after diagnosis of candidemia. All surviving patients (n=35) in 2016 received antifungal treatment compared with 24/28 (86%) in 2013 (p=0.0344). Follow-up blood cultures were performed in 25/35 (71%) in 2016 compared with 10/25 (40%) in 2013 (p=0.0046). Survival in the intervention compared with the pre-intervention group did not differ significantly (p=0.58) one year after the diagnosis of candidemia was made. However, patients with candidemia often have multiple serious comorbidities. Individualized bedside AFS significantly improves adherence to recommendations for patients with Candida fungemia, especially guideline-oriented diagnostics and therapy. Improving the prognosis of patients with candidemia remains a huge challenge for AFS.

Die Probenqualität bestimmt ganz entscheidend das mikrobiologische Untersuchungsergebnis. Durch Fehler in der Präanalytik und mangelhaftes Probenmaterial sind die diagnostischen Möglichkeiten eingeschränkt. Inadäquate Therapieentscheidungen, zusätzliche Mehrkosten und eine Belastung des Patienten durch wiederholte Probenentnahmen sind vermeidbare Folgen. Nur eine optimale Präanalytik ermöglicht genaue, zeitnahe und klinisch relevante Ergebnisse. Publication Date: 03 August 2020 (online) Georg Thieme Verlag KG Stuttgart · New York