Antibiotic resistance & pathogen profile in ventilator-associated pneumonia in a tertiary care hospital in India

Abstract

Background & objectives:Ventilator-associated pneumonia (VAP) is an important hospital-acquired infection with substantial mortality. Only a few studies are available from India addressing the microbiological aspects of VAP, which have been done with small study populations. This study was carried out in the intensive care units (ICUs) of a tertiary care hospital to assess the profile of pathogens and to determine the pattern of antimicrobial resistance.Methods:This was a retrospective study of clinically suspected cases of VAP. Over a three year period, a total of 247 cases in 2011, 297 in 2012 and 303 in 2013 admitted in ICUs on mechanical ventilation with clinical evidence of VAP were included in our study. The endotracheal aspirate samples from these suspected cases were subjected to quantitative culture technique, and colony count of ≥105 colony forming units/ml was considered significant. Antimicrobial susceptibility test for the isolates was done.Results:VAP rates of 44.1, 43.8 and 26.3 were seen in 2011, 2012 and 2013, respectively. In all the three years, non-fermentative Gram-negative bacilli were the predominant organisms, followed by Pseudomonas spp. and Klebsiella spp. Staphylococcus aureus exhibited a downwards trend in prevalence from 50.0 per cent in 2011 to 34.9 per cent in 2013. An increase in vancomycin-resistant enterococci was seen from 4.3 per cent in 2012 to 8.3 per cent in 2013, while methicillin resistance amongst the S. aureus crossed the 50 per cent mark in 2013. An increasing trend in resistance was shown by Pseudomonas spp. for piperacillin-tazobactam (PTZ), amikacin and imipenem (IPM). For the non-fermenters, resistance frequency remained very high except for IPM (33.1%) and polymyxin-B (2.4%).Interpretation & conclusions:Our findings show VAP as an important problem in the ICU setting. The incidence of multidrug-resistant pathogens was on the rise. The resistance pattern of these pathogens can help an institution to formulate effective antimicrobial policy. To have a comprehensive pan-India picture, multicentric studies are needed.

Microbiological profile of ventilator-associated pneumonia among intensive care unit patients in tertiary Egyptian hospitals

“…Similarly, in an Indian study, the most frequent microorganisms isolated from VAP patients were, in order, Klebsiella spp. and P. aeruginosa [27]. Additionally, previous studies in India and the same geographical country of our study Egypt on VAP reported Klebsiella spp.…”

Authors' Response

“…First, the authors have raised the appropriateness of including Candida as a pathogen for ventilator associated pneumonia (VAP), since it is extremely rare and lung biopsy is the only definitive method for diagnosis of Candida pneumonia. Earlier, the data from 24 investigations conducted with ventilated patients for a total of 1,689 episodes and 2,490 pathogens revealed Candida as an aetiological agent in 0.9 per cent 2 while in our study, it was 2.0 per cent (63 out of 3084 clinically suspected cases) 3 which may not be termed substantially high. We agree that the existing bronchoscopic or non-bronchoscopic specimens are not appropriate for diagnosis of Candida pneumonia and Candida recovered from such samples signifies colonization.…”

A Study on Bacterial Etiology of Ventilator Associated Pneumonia and its Antimicrobial Pattern

“…10 In critical ill patients, the longer period of mechanical ventilation and hospital stay increases colonization rate and the incidence of resistant bacteria. 14 15 In a study from North India, Mehndiratta, et al have reported isolates of Pseudomonas, Klebsiella and E. coli with 100% sensitivity to imipenem and all the gram-positive isolates studied were sensitive to linezolid. 16 In this study,the most effective antibiotic against gram negative bacilli was found to be Imipenem followed by Piperacillin tazobactam.…”