Incidence and Clinical Outcome of Multidrug-resistant Gram-negative Bacteria Associated Sepsis in ICU

INTRODUCTION: CDC defines multi-drug resistant organisms (MDRO) as bacteria that are resistant to one or more classes of antimicrobial agents recommended as first line therapy(4). Critically ill patients in intensive care unit (ICU) have chronic underlying diseases and immune dysfunction which in association with invasive procedures and broad spectrum antibiotics increase risk of healthcare associated infection(1,2) which remain one of the most serious concerns in critically ill patients. Lack of antimicrobial stewardship program and inappropriate use of Antimicrobial has led to emergence of drug resistance(3). Critically ill patients in ICU has highest incidence of MDROs across all hospital departments. OBJECTIVES: Objective of this study was to determine the incidence of multi-drug resistant gram-negative bacilli (MDR-GNB) infections in the critically ill patients from adult ICU, as well as the clinical outcomes with regard to 28-days mortality, ICU and hospital length of stay and duration of mechanical ventilation. METHODS: A prospective observational study was conducted among adult patients admitted in ICU of Dr B L Kapur Memorial hospital from December 2022 to March 2023. Patients infected with multi-drug resistant gram negative bacteria and non-multi-drug resistant gram-negative bacteria were included. Demographic, clinical profiles and outcomes (28-days mortality, ICU and hospital length of stay and duration of mechanical ventilation) were documented. RESULTS: Incidence rate of multi-drug resistant gram-negative infections was 20 per 100 admitted patients (100/506) with 109 episodes. Klebsiella Pneumoniae (32%, 35/109) was the commonest followed by Acinetobacter baumannii (22.9%,25/109); Escherichia coli (22.9%,25/109) and Pseudomonas species (12.8%,14/109). 28-days mortality among patients in the MDR group (40%, 40/100) (p < 0.001) was higher than those in the non-MDR GNB group (27.2%, 3/11) (p = 0.4) and uninfected group (11%, 40/358) (p < 0.001). Low mortality in E.coli compared to others was highly significant (p = 0.005) and higher mortality in Acinetobacter was significant (p=0.027) compared to others. Duration of invasive mechanical ventilation and ICU and hospital length of stay were longer in patients with MDR-GNB infection however, this was statistically insignificant. CONCLUSIONS: Present study showed higher 28-days mortality with MDR-GNB infection. Patients with MDR-GNB infection needed prolonged duration of mechanical ventilation and longer ICU and hospital stay. Inadequate empirical antibiotic therapy was a major contributor to MDRO infection.