Bacteriological profile and antimicrobial susceptibility patterns of bloodstream infections in a tertiary care hospital, aimsr, bathinda

Objectives: Blood stream infections have many serious consequences like shock, disseminated intravascular coagulation, multiple organ failure and even death. Blood culture is thus  necessary to identify causative agents of BSI’s and to choose an appropriate antimicrobial therapy. A cross-sectional study was conducted with an objective to determine the  bacteriological profile and antibiogram of organisms causing bloodstream infection for a period of 6 months from January 2019  to June 2019. 
Methods: Blood specimens were received in Bacteriology laboratory in blood culture bottles and incubated in BacT/ALERT® 3D system (bioMerieux, Durham, NC, USA) a fully automated blood culture system for detection of aerobic bacteria. Identification of isolates was done by studying their colony characteristics, Gram staining morphology and various biochemical reactions. Antimicrobial susceptibility testing was done by Kirby Bauer disc diffusion method and results were interpreted as per Clinical Laboratory Standards Institute guidelines. 
Results: A total of 555 blood samples were processed during the study period. Among them, 94 (16.8%) yielded significant growth and 461 (83.2%) samples showed no growth. Coagulase-negative Staphylococci (CONS) were the most common isolates among Gram-positive cocci whereas  E. coli was the most commonly isolated Gram-negative bacilli. Gram positive isolates were found to be highly susceptible to vancomycin and linezolid followed by nitrofurantoin, clindamycin and gentamicin. Gram negative bacteria showed  maximum susceptibility to colistin  followed by amikacin,  imipenem and meropenem.
Conclusion: There is an increasing emergence of antimicrobial resistance in  both Gram positive and Gram negative bacteria indicating active microbial surveillance in all clinical settings. Monitoring of data regarding the prevalence of bacteria and their resistance patterns would benefit in formulating policies for empirical antimicrobial therapy particularly in developing countries.