Bacteriological Profile and Antibiotic Sensitivity Pattern of Isolates of the Patients Admitted in Medical Intensive Care Unit of a Tertiary Care Hospital

Nosocomial infections are one of the leading causes of morbidity and mortality in hospitalized patients especially the critically ill patients in the Intensive care unit (ICU) where a large number of drugs are administered to the patient which leads to emergence antibiotic resistant pathogens.

1. To determine the Bacteriological profile of isolates of the patients admitted in MICU.

2. To determine the antibiotic sensitivity pattern of the isolates.

A prospective study was conducted in the MICU of Vydehi Institute of Medical Sciences and Research Centre Bangalore for a period of 4 months from October 2015 to January 2016. Patients developing fever after admission in MICU for more than 48 hours indicating hospital acquired infection were included in the study and various clinical specimens like blood, sputum, Pus Swab, Catheter tip, tracheal aspirate, sterile body fluids, urine etc were collected. The isolates were identified by standard procedures and tested for antibiotic sensitivity pattern (MIC of antibiotics) according to Vitek 2 compact system.

A total of 300 samples received 230 (76.7%) yielded growth of bacteria. Total 165 (72%) isolates were gram negative and 65 (28%) were gram positive isolates. Most commonly isolated bacteria was Klebsiella pneumoniae 62 (27%) followed by Staphylococcus aureus 60 (26%), Pseudomonas aeruginosa 33 (14.3%). Klebsiella pneumoniae was predominantly isolated from sputum (44%), Staphylococcus aureus (57%) from blood. Non fermenter gram negative bacilli like Pseudomonas aeruginosa (23.5%) from sputum and Escherichia coli (44%) predominantly from urine. Klebsiella pneumoniae was sensitive to amikacin (81%), piperacillin/tazobactam (78%) and colistin (89%). Pseudomonas aeruginosa was sensitive to amikacin (88%), piperacillin/tazobactam (77%), colistin (90%) ceftazidime (69%) Acinetobacter baumanii was sensitive to amikacin (75%), piperacillin/Tazobactam (79%), and colistin (92%) ceftazidime (65%). 58.6% Staphylococcus aureus isolates were MRSA. All MRSA were sensitive to Vancomycin (100%) and Linezolid (100%).

MICU patients are more prone to hospital acquired infections by Klebsiella pneumoniae and Staphylococcus aureus commonly. Colistin showed 90% sensitivity to gram negative isolates and all MRSA isolates were sensitive to Vancomycin (100%) and Linezolid (100%).