Microbiological profile of infection in intensive care unit and their antimicrobial susceptibility pattern with special reference to metallo beta-lactamases and AmpC

Abstract

Background: Throughout the world multidrug-resistant healthcare-associated infections (HAI) are one of the leading causes of morbidity and mortality among hospitalized patients, leading to a major burden on public health system of any country. An intensive care unit (ICU) patient has five- to seven-folds higher risk of HAI and ICU infections contribute to 20–25% of all HAI. Objective: This prospective study was designed to isolate and identify the bacterial etiology, their antimicrobial susceptibility pattern and to detect the production of the metallo β-lactamases (MBL) and AmpC-β-lactamases in multidrug-resistant gram negative isolates. Material and Methods: The study was conducted for the period of 1 year. During the period a total 196 samples were collected and processed as per Clinical and Laboratory Standards Institute guidelines. Result: The majority of bacterial isolates causing HAI were found to be Gram-negative bacilli (73.68%). Acinetobacter species followed by Pseudomonas aeruginosa, Escherichia coli, Citrobacter species, Klebsiella species, and Enterobacter species, respectively. Gram-positive cocci were accounted 26.31% isolates. All isolates were multidrugresistant. Among Gram negative bacilli, 38.10% AmpC producer, 35.71% MBL, and 16.67% were coproducer of AmpC and MBL. Conclusion: Microbiological profile of infection in ICU of our institute was multidrug-resistant, and in many isolates, drug resistance was due to the production of MBL and AmpC-β-lactamases, which represents basic information for future monitoring of HAI and could be repeated periodically. Thus, the future prevention program should focus on patients with a longer length of stay and those with invasive devices.