[Anaerobic bacteremias in an adult University Hospital in Córdoba, Argentina: a 26-year análisis]

Introduction: The aim of this study is to evaluate the incidence of anaerobic bacteremia over a 26-year period. : Conclusion: The incidence of anaerobic bacteremia was 1.69% in the 26-year period, with most of the patients involved being elderly and with different comorbidities. Methods: Retrospective observational study of blood cultures processed between January 1996 and December 2021 in the Bacteriology laboratory of the Hospital Nacional de Clínicas, considering two time periods (IP and IIP). Isolated species, demographic variables, origin, type of bacteremia, associated focus, and comorbidities were analyzed. Results: 53,553 blood cultures were processed, of which 9.5% were positive and of these, 86 (1.69%) corresponded to anaerobic bacteremias with 96 isolated species, 53.1% gram-positive bacteria, and 46.9% gram-negative bacteria. There were older patients in IIP compared to IP (p=0.0004). Outpatient acquisition predominated in IIP and nosocomial acquisition in IP (p= 0.0041). Polymicrobial bacteremias represented 31.4%, with no significant differences. The foci were abdominal (32.6%), skin and soft tissue (18.6%) throughout the period; neoplasia (20.9%), abdominal surgery (16.3%) and diabetes (11.6%) as comorbidities. Bacteroides/Parabacteroides of the fragilis group (29.2%), Clostridium perfringens (13.5%) and Clostridium septicum (10.3%) were isolated. Clostridium species predominated in IP and Bacteroides/Parabacteroides in IIP (p= 0.0027). Conclusion: The incidence of anaerobic bacteremia was 1.69% in the 26-year period, with most of the patients involved being elderly and with different comorbidities.