Bacteriological Spectrum and Antibiotic Susceptibility of Non-Fermenting Gram-Negative Bacilli in Bloodstream Infections

Introduction: Bloodstream infection (BSI) is one of the major challenges faced in hospitals as it increases patient stay, healthcare cost, and mortality rate. Non-fermenting gram-negative bacilli NFGNB have emerged as a significant pathogen in hospital settings and BSI due to these NFGNB are on the rise. Due to the extensive resistance of NFGNB to antimicrobials, it becomes crucial to understand the antibiotic susceptibility pattern of these organisms in different clinical settings.Aim and objective: To determine the prevalence of non-fermenting gram-negative bacilli (NFGNB) and their antibiotic susceptibility pattern in admitted patients with bloodstream infections(BSI)at a tertiary care hospital.Material & Methods: A retrospective analysis of blood culture samples was done over a period of 1 year (1stApril 2022 to 31st March 2023) in the Department of Microbiology at a tertiary care hospital. All samples were processed as per standard microbiological techniques. Antimicrobial susceptibility was interpreted according to CLSI 2022 guidelines.Results: In this study, the prevalence of NFGNB was 3.42%. The most common NFGNB isolated were Acinetobacter species and Pseudomonas species. The other NFGNB isolated were Stenotrophomonas maltophilia, Sphingomonaspaucimobilis, Burkholderiacepacia complex, Elizabethkingiameningoseptica and Achromobacterdenitrificans. Acinetobacter species showed multidrug resistance while other NFGNB were susceptible to commonly tested antibiotics.Conclusion: The NFGNB which were previously considered as contaminants or commensals have emerged as important pathogens causing serious infections. This study depicts the increasing number of non-fermenters in bloodstream infections among patients admitted in tertiary care hospital. Hence identification of NFGNB and their appropriate antimicrobial susceptibility testing can help clinicians to initiate the empirical treatment.