Characterisation of aerobic bacteria isolated from endotracheal aspirate in adult patients suspected ventilator associated pneumonia in a tertiary care center in Mangalore

ABSTRACT

Despite advances in antimicrobial therapy, better supportive care modalities and use of a wide range of preventive measures, ventilator-associated pneumonia [VAP] continues to be an important cause of morbidity and mortality in intensive care unit [ICU]. VAP requires a rapid diagnosis and initiation of appropriate antibiotic treatment, to prevent mortality and morbidity. Inappropriate and inadequate antibiotic treatment causes emergence of drug resistance in pathogens and poor prognosis in patients. Early detection of pathogens causing VAP helps to control their spread by administration of suitable antibiotics and proper infection control measures. The study was conducted to know the pathogens causing VAP in Fr. Muller Medical College Hospital, Mangalore, and their susceptibility pattern. A total of 100 patients, on mechanical ventilation for more than 48 h, who were suspected to have VAP were included in the study between December 2008 and November 2009. Their endotracheal aspirates [ETAs] were collected and processed. From 100 ETA, 138 isolates of count >10[5] CFU/ mL were characterized and antibiogram was determined using standard antibiotics regime. Incidence of VAP was found to be 44.2% among the mechanically ventilated patients. Klebsiella pneumoniae [34%] was the most common pathogen isolated, followed by Pseudomonas aeruginosa [20%]. Among them, most of the K. pneumoniae and P. aeruginosa isolates were resistant to penicillins, cephalosporins, fluoroquinolones was observed but were sensitive to piperacillin/tazobactum, cefaperazone/sulbactum, and carbapenems. All isolates were sensitive to amikacin. The present study shows prevalence of multidrug-resistant organisms in the study region. Klebsiella species was the most common pathogen isolated in ETA. Acinetobacter species were the most resistant pathogens prevailing in our ICU setup, leading to the increased mortality in the ventilated patients. Patients with chronic obstructive pulmonary disease is the most common predisposing factor for VAP in the study group