Antimicrobial susceptibility patterns of respiratory Gram-negative bacterial isolates from COVID-19 patients in Switzerland

Annals of Clinical Microbiology and Antimicrobials

Claudio Tirso Acevedo¹  Silvio Daniel Brugger¹  Philipp Karl Buehler²  Marina Gysin³  Katja Becker³  Klara Haldimann³  Karl Bulut³  Elias Bodendoerfer³  Sven N. Hobbie³  Frank Imkamp³ 

[1] Department of Infectious Diseases and Hospital Epidemiology, University Hospital Zurich, University of Zurich, Raemistrasse 100, 8091, Zurich, Switzerland;Institute for Intensive Care Medicine, University Hospital Zurich and University of Zurich, Raemistrasse 100, 8091, Zurich, Switzerland;Institute of Medical Microbiology, University of Zurich, Gloriastrasse 30, 8006, Zurich, Switzerland;

关键词: COVID-19;    Superinfection;    Ventilator-associated bacterial pneumonia;    Antimicrobial resistance;    Aminoglycoside;    Apramycin;   

DOI  :  10.1186/s12941-021-00468-1

来源: Springer

【 摘 要 】

BackgroundBacterial superinfections associated with COVID-19 are common in ventilated ICU patients and impact morbidity and lethality. However, the contribution of antimicrobial resistance to the manifestation of bacterial infections in these patients has yet to be elucidated.MethodsWe collected 70 Gram-negative bacterial strains, isolated from the lower respiratory tract of ventilated COVID-19 patients in Zurich, Switzerland between March and May 2020. Species identification was performed using MALDI-TOF; antibiotic susceptibility profiles were determined by EUCAST disk diffusion and CLSI broth microdilution assays. Selected Pseudomonas aeruginosa isolates were analyzed by whole-genome sequencing.ResultsPseudomonas aeruginosa (46%) and Enterobacterales (36%) comprised the two largest etiologic groups. Drug resistance in P. aeruginosa isolates was high for piperacillin/tazobactam (65.6%), cefepime (56.3%), ceftazidime (46.9%) and meropenem (50.0%). Enterobacterales isolates showed slightly lower levels of resistance to piperacillin/tazobactam (32%), ceftriaxone (32%), and ceftazidime (36%). All P. aeruginosa isolates and 96% of Enterobacterales isolates were susceptible to aminoglycosides, with apramycin found to provide best-in-class coverage. Genotypic analysis of consecutive P. aeruginosa isolates in one patient revealed a frameshift mutation in the transcriptional regulator nalC that coincided with a phenotypic shift in susceptibility to β-lactams and quinolones.ConclusionsConsiderable levels of antimicrobial resistance may have contributed to the manifestation of bacterial superinfections in ventilated COVID-19 patients, and may in some cases mandate consecutive adaptation of antibiotic therapy. High susceptibility to amikacin and apramycin suggests that aminoglycosides may remain an effective second-line treatment of ventilator-associated bacterial pneumonia, provided efficacious drug exposure in lungs can be achieved.

【 授权许可】

CC BY