A bacteriological study of nosocomial infections in an intensive care unit in a tertiary care hospital

Nosocomial infections are applied to infections developing in hospitalized patients, not present or without incubation at the time of their admission. The present study was undertaken to determine most predominant bacterial isolates in nosocomial infections of ICU, their antibiotic sensitivity pattern and to identify the specific age group of people at a higher risk of acquiring nosocomial infections in ICU. 100 samples were studied over a period of 3 months in a tertiary care hospital. Clinical specimens collected from patients admitted in ICU at least for 48 hours with suspicion of nosocomial infections were included. Isolates were identified by standard procedures and antibiotic sensitivity done by Kirby Bauer method. 38(38%) of the clinical specimens were culture positive while 62 specimens showed no growth. Male to Female ratio was 2.03:1. Of 40 isolates recovered, 28(70%) were Gram negative bacilli, eight (20%) were Gram positive cocci, one (2.5%) Candida spp., three (7.5%) were non-fermenters. The most common organisms isolated was Klebsiella pneumoniae (42.5%) followed by Methicillin Resistant Staphylococcus aureus (15%). All isolates of Klebsiella pneumoniae were sensitive to Imipenem and Piperacillin-Tazobactam acid. Nosocomial infections was found to be more prevalent in young adults (21 to 30 years). This study clearly documents a high prevalence rate of nosocomial infections in the ICU, Gram-negative bacteria being the most common causative pathogens. There is an alarmingly high rate of resistance to cephalosporins and β lactam-β-lactamase inhibitors among Gram negative organisms. Judicious use of older and newer antimicrobial agents is essential to prevent the emergence of multi drug resistant bacteria in the ICU. We recommend that education and awareness among health care workers as well as adherence to standard guidelines for prevention of nosocomial infections.