Abstract
Ventilator-associated pneumonia (VAP) represents an important nosocomial infection, frequently encountered in intensive care unit (ICU) settings which results in prolonged hospitals stays. The nosocomial infections caused by Burkholderia cepacia complex (BCC) bacteria pose a significant challenge in healthcare settings owing to their intrinsic resistance to many antibiotics. This study investigates the antimicrobial susceptibility patterns and mechanisms of carbapenem resistance among BCC bacteria from VAP patients and the ventilator tubing. The blood and respiratory specimens from patients diagnosed with VAP were collected. In addition, the ventilators were also screened for the presence of BCC bacteria. The susceptibility profiling of BCC isolates was performed against the various antimicrobial agents, and screening for acquired beta-lactamase enzymes was conducted by polymerase chain reaction. Out of the total 134 patients with BCC-associated VAP, B. cepacia, Burkholderia multivorans, and Burkholderia cenocepacia was 68.7% (n = 92), 18.7% (n = 25), and 12.7% (n = 17). Overall, the BCC isolates showed varying susceptibility to different antibiotics: 76.9% were susceptible to chloramphenicol, 76.1% to minocycline, 69.4% to meropenem, 60.4% to ceftazidime, 51.5% to trimethoprim-sulfamethoxazole, and 50% to levofloxacin. Resistance to ceftazidime (51/92, 55.4%) and meropenem (36/92, 39.1%) was exclusively observed in B. cepacia isolates, and all isolates of B. multivorans and B. cenocepacia were found to be susceptible to both beta-lactam drugs. Among the 134 clinical isolates, 15 were found to harbor the bla (NDM) variants, that is, bla (NDM-1) and bla (NDM-5). All carbapenem-resistant isolates from the ventilator tubing were identified as B. cepacia and were found to harbor either the bla (NDM-1) or the bla (NDM-5) variants. The observed increase in resistance and the emergence of acquired beta-lactamases among BCC isolates highlight a concerning trend that could potentially lead to serious outbreaks.