Prevalence and resistance profiles of ESBL-producing Gram-negative bacteria in ICU patients in India

Background: The global rise of extended-spectrum β-lactamase (ESBL)-producing Gram-negative bacteria in intensive care units (ICU) is a significant public health issue. This study aims to evaluate the microbial profile and resistance pattern of ESBL producers, together with the overall burden of multi-drug resistant (MDR) and extensively drug-resistant (XDR) GNB isolates in the ICU. Methods: This prospective observational study was conducted over a period of six months in the ICU of a tertiary care hospital. ESBL detection and antibiotic susceptibility tests were performed using the VITEK II system according to the Clinical and Laboratory Standards Institute (CLSI) criteria. Results: A total of 130 patients were included, with 83 (63.8%) males and a mean (±SD) age of 57.34 (±15.52) years. Hypertension (43%) and diabetes (35.3%) were the most common comorbidities, while gastrointestinal disorder was significantly more frequent in non-survivors (p = 0.002). Drain insertion (p = 0.017), a length of stay between 11 and 20 days (p = 0.008), and higher SOFA and APACHE II scores (p < 0.05) were significantly associated with mortality. The ICU mortality rate was 29.3%. Among all GNB isolates, 48 (36.9%) were ESBL producers, predominantly yielded from urine. Escherichia coli (60.5%) and Klebsiella pneumoniae (25%) were the most common ESBL producers, showing 90 to 100% resistance to cephalosporins and fluoroquinolones. MDR and XDR GNB isolates accounted for 49.2% and 13.9%, respectively. Conclusions: A high prevalence of ESBL-producing organisms was observed in the ICU, underscoring the need for effective infection control and antibiotic stewardship programs.