Emergence of Multidrug-Resistant and Extensively Drug-Resistant Non-Fermenting Gram-Negative Bacilli in a Tertiary Hospital in India

Introduction: Non-fermenting Gram-negative bacilli (NFGNB), particularly the Acinetobacter baumannii complex (ABC) and Pseudomonas aeruginosa, are common causes of infections in both hospitalized patients and outpatients, posing significant clinical and therapeutic challenges. The primary objective of this study was to conduct a comprehensive analysis of NFGNB, specifically ABC and P. aeruginosa, isolated from pus specimens obtained from both hospitalized patients and outpatients. Methods: This study investigated the antibiotic resistance patterns of NFGNB, focusing on ABC and P. aeruginosa, isolated from pus samples collected from both hospitalized patients and outpatients. The isolates were tested for multidrug resistance (MDR) and extensive drug resistance (XDR) using standardized microbiological protocols. The data were analyzed using descriptive statistics to summarize the findings. Results: Out of 1234 pus samples received, 117 (9.5%) NFGNB were isolated, accounting for 30% of the total Gram-negative bacilli (GNB) isolates. The majority of NFGNB (82.9%, n = 97/117) were isolated from inpatients, with surgical site infections being the most common clinical condition (33.3%, n = 39/117). Among the NFGNB isolates, P. aeruginosa was the predominant species (76.9%, n = 90/117), followed by A. baumannii (22.2%, n = 26/117). Antimicrobial susceptibility testing revealed that 37.7% (n = 34/90) of P. aeruginosa isolates were MDR and 13% (n = 12/90) were XDR, while 65% (n = 17/26) of A. baumannii isolates were MDR and 26.9% (n = 7/26) were XDR. Conclusion: This study highlights the emergence of NFGNB as significant nosocomial pathogens, exhibiting a high degree of resistance to commonly used antibiotics. The findings underscore the urgent need to enhance and strictly implement effective antibiotic stewardship policies, including the development of new antibiotic regimens and antimicrobial resistance surveillance programs, to combat the growing resistance of nosocomial pathogens and ultimately improve patient outcomes.

Emergence of Multidrug-Resistant and Extensively Drug-Resistant Non-Fermenting Gram-Negative Bacilli in a Tertiary Hospital in India Keywords:

Acinetobacter baumannii , Multidrug-resistant (MDR) , Extensive drug resistant (XDR) , Non-fermenting Gram-negative bacteria (NFGNB) , Pseudomonas aeruginosa