Prevalence of multidrug-resistant Acinetobacter baumannii in intensive care unit admitted patients from a hospital in Dhaka City, Bangladesh

Abstract

Background: Multidrug-resistant Acinetobacter baumannii has become a concern in the world of healthcare. The most common source of infections acquired in hospitals is an opportunistic bacterial pathogen called A. baumannii. It has become a significant nosocomial pathogen that has claimed many lives throughout the world, including in Bangladesh. This study's goals were to determine the pathogen's prevalence and contribute to the development of a local antibiogram database so that future treatment approaches can be improved. Materials and Method: From August 2022 to December 2022, a total of 72 pathogenic Gram negative clinical isolates of Acinetobacter spp. were collected from ICU- admitted patients, and tested at the clinical microbiology laboratory of a private hospital in Dhaka, Bangladesh. Most of the isolates were recovered from tracheal aspirates, sputum, pus, and wounds. The collected isolates were further analyzed at BRACU MNS research laboratory presumptively by cultural methods for the presence of A. baumannii using highly selective Leeds Acinetobacter Medium (LAM) and A. baumannii was confirmed by conventional polymerase chain reaction (PCR) using the primers of blaOXA-51. Findings: From all the 72 clinical isolates, a total of 24 A. baumannii isolates tested positive using conventional Polymerase Chain Reaction (PCR) and Agarose Gel Electrophoresis, determining the prevalence as 33%. All confirmed isolates were characterized by Antimicrobial Susceptibility Testing (AST), performed following the disk diffusion method as recommended by Clinical Laboratory and Standards Institute (CLSI). The A. baumannii isolates confirmed Multidrug resistance (MDR) by showing antimicrobial resistance to more than three antimicrobial categories, such as 100% resistance to Ampicillin (AMP), 70.8% resistance to Cefepime (CPM), Ceftazidime (CAZ), and Levofloxacin (LE), 66.7% resistance to Imipenem (IMP), 62.5% to Gentamicin (GEN), Amikacin (AK) and Tetracycline (TE), and 58.3% resistance Piperacillin-tazobactam (PIT). However, the highest sensitivity result showed 62.5% for Doxycycline (DO) and 58.3% for Trimethoprim-sulfamethoxazole (COT). Conclusion: This research suggests that the supervision of antimicrobial resistance of A. baumannii is essential. The prevalence will help in the implementation of better infection control measures, and a local antibiogram update will increase our awareness of the patterns of antimicrobial resistance in healthcare facilities.