Isolation of non-fermenting Gram negative bacteria in respiratory tract infections

Abstract

Respiratory tract infections are the most common diseases that are associated with mortality and morbidity. They are often misdiagnosed due to its nonspecific presentation in clinical settings. The risk factors of RTI vary geographically and timely(1). So it is important to evaluate more for RTI causative agents.The non-fermentative Gram negative bacilli (NFGNB) are often associated with RTI. The NFGNB are a group of several different aerobic, non-sporing, Gram negative bacilli that either unable to utilize carbohydrates as a source of energy or withhold them through metabolic pathways other than the fermentation. The study was undertaken to identify various non- fermenters by additional conventional tests, isolated from patients having respiratory tract infection in department of Microbiology, SVPPGIP and SCBMCH Medical college, a Tertiary Care Center, Odisha. Our study also line up the singnificant role of NFGNB as respiratory pathogens.391 (14.6 %) non-fermenters were isolated from 2678 clinical specimens. Out of which NFGNB(391 samples), a total of 143 (36.57%) were from various respiratory samples were included in this study and were isolated on MacConkey and blood agar plates incubated at 35°C for 24-48 hours. Patients mostly belonged to age group of 65 to 80 years and were 96(67%)male. complex 67(46.8%) was the commonest isolate followed by 56(39.1%). While other NFGNB like were isolated in few respiratory samples.The most effective antibiotics were Tigecycline and Polymyxin B/ Colistin, however majority of them showed multidrug resistance.