Research Articles






S Balakrishnan, N Shaji, RP Jakribettu, R Boloor, MS Baliga


ABSTRACT: Antimicrobial resistance (AMR) is a major issue especially in patients admitted in Intensive care units. Irrational overuse and misuse of antibacterial drugs has made the pathogens resistant to them. In eastern countries, infections in ICU are caused mainly by Gram negative pathogens, which are MDR. Hence, this study was conducted to study the gram negative pathogens causing ICU infections in our centre and their drug resistance pattern. Material and Methods: It was a prospective study done for four months (Dec 2015-March 2016) in different ICU of the tertiary care hospital. All patients admitted for more than 48 hours in ICU and having symptoms of infections were included in the study. The relevant sample was collected and preceded as per Standard microbiological procedure and Antimicrobial susceptibility test was done by Kirby Bauer’s disc diffusion method as per CLSI guidelines. Results: During the study period, 327 patients were admitted in ICUs, of which 173 were admitted for more than 2 days. A total of 1013 samples were received from ICU, only 245 samples showed significant bacterial growth. Majority of the isolates were Gram negative pathogens accounting for 209 (73.8%) of the 283 total pathogens isolated. Respiratory infection and Urinary tract infections, were the commonest infections accounting for around 25% each. Klebsiella species and Acinetobacter species were the commonest Gram negative pathogen isolated. Klebsiella species and Escherichia coli were resistant to most of the commonly used drugs like aminoglycosides, 3rd Generation cephalsporins (3GC) and  β lactam – β lactamase Inhibitor (BL-BLI) combination, with only resort being  carbapenems. But, in case of Acinetobacter species, 92% of the isolates were resistant to carbapenems. Conclusion: The infections in patients admitted in ICU are predominantly caused by MDR Gram negative bacteria. The commonly administered antibacterial drugs in ICU like aminoglycosides, 3GC and BL-BLI are not effective in combating these pathogens. It’s high time to implement antibiotic stewardship programme to combat this menace of drug resistance.


KEY WORDS: ICU infections, Nosocomial infections, MDR-GNB


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