Role of Multidrug-resistant Pathogens in Ventilator-Associated Pneumonia in a Tertiary Care Hospital in India

Aim: Ventilator-associated pneumonia (VAP) is the second most common infection acquired in the intensive care unit (ICU). Bacteriological profiles cause VAP and their susceptibility patterns vary in different institutions. Methods: A prospective study was conducted from June ۲۰۱۷ to May ۲۰۱۸ in a tertiary care hospital as per the recent NHSN guidelines in finding the incidence of VAP and further determining the etiological agents by both conventional and automated methods. The combination disk method (Phenotypic confirmatory test), ampicillin C (AmpC) disk test, modified carbapenem inactivation method, imipenem/ethylenediamine tetraacetic acid combined disc test, and cefoxitin disk test were performed for the detection of extendedspectrum beta-lactamases (ESBL), AmpC β-lactamases, carbapenemases, metallo-beta-lactamases (MBL), and methicillin-resistant Staphylococcus aureus, respectively. Results: Among ۱۰۴ patients, ۳۱ cases developed PVAP (possible VAP) during their ICU stay; of these cases, two patients had two episodes of VAP each, and the incidence of VAP was ۳۲%. The most common isolate was Acinetobacter baumannii (۳۸%), followed by Pseudomonas aeruginosa (۲۲%), Klebsiella pneumoniae (۱۶%), and Escherichia coli (۱۳.۵۱%). Twenty (۵۴%) of the ۳۷ VAP pathogens were multidrug resistant. ESBL was produced by ۴۰% and ۶۷% of E. coli and K. pneumoniae, respectively. MBL was produced by ۲۵% of P. aeruginosa. In addition, AmpC beta-lactamases were produced by ۱۸% each of the Enterobacteriaceae and non-fermenters, respectively. One of the two S. aureus isolates was methicillinresistant. Conclusion: The majority of VAP cases in our setting were caused by highly resistant strains. The frequency of specific multidrug resistance pathogens causing VAP may vary due to hospital, patient population, exposure to antibiotics, type of ICU patients, and changes over time, emphasizing the need for timely local surveillance data.

کلیدواژه ها:

Ventilator-associated pneumonia ، Extended-spectrum beta-lactamase ، Modified carbapenem inactivation method ، Intensive care unit ، Metallo-beta-lactamase ، Multidrug resistance