Exploring Multi-Drug Resistance Mechanisms in MBL-Producing Gram-Negative Bacteria Isolated from Hospitalized Patients: A Phenotypic Analysis

Multi-drug resistance (MDR) is a serious threat to the efficacy of therapeutic therapies for antimicrobial resistance (AMR), which is a worldwide health problem. Gram-negative bacteria that produce metallo-beta-lactamase (MBL) have become important sources of MDR, making it more difficult to treat infections in hospitalized patients. Objective: The Gram-negative bacteria (GNB) that produces MBL was isolated from hospitalized patients. Method: Fifty-five Acinetobacter baumannii isolates were analyzed in this Phenotypic Analysis. These isolates were taken from specimens of sputum that came from adult Intensive Care Unit (ICU) patients. Gram-negative panels, namely the "VITEK 2 AST–N233 and AST-XNO5 susceptibility cards," were used for the identification and testing of each isolate in compliance with the Clinical recommendations. Multi-Drug Resistance (MDR) isolates were identified using Polymerase Chain Reaction (PCR) and Minimal Inhibitory Concentrations (MIC) experiments. Result: A 100% resistance to cefepime, ciprofloxacin, aztreonem, piperacillin and ceftazidime was detected in all 55 isolates. The 90% of samples indicated resistance to levofloxacin, but 6% to colistin. A significant prevalence of resistance genes was found; 95% of samples tested positive for blaOXA-23 and percentages ranging from 3% to 12% were positive for blaOXA-24, blaOXA-51, blaOXA-143 and blaOXA-235. 21% expressed KPC, 85% carried Integron-1 and 25% carried NDM-1. The knowledge acquired aids in improving comprehension of the difficulties presented by MBL-producing bacteria, directing the creation of focused treatments and influencing infection control procedures in hospital environments.