Abstract
BACKGROUND: Lower respiratory tract infections (LRTIs) are the most frequent infections among patients in Intensive care units (ICUs). AIMS: To know the bacterial profile and determine the antibiotic susceptibility pattern of the lower respiratory tract isolates from patients admitted to the ICU. SETTINGS AND DESIGN: Tertiary care hospital, retrospective study. MATERIALS AND METHODS: Transtracheal or bronchial aspirates from 207 patients admitted to the ICU were cultured, identified, and antibiotic sensitivity was performed by standard methods. STATISTICAL ANALYSIS USED: SPSS software was used for calculation of % R of 95% confidence interval (CI). RESULTS: Of 207 specimens, 144 (69.5%) were culture positive and 63 (30.4%) showed no growth. From 144 culture positives, 161 isolates were recovered, of which 154 (95.6%) were Gram negative bacilli (GNB). In 17 (11.0%) patients, two isolates per specimen were recovered. The most common GNB in order of frequency were Pseudomonas aeruginosa (35%), Acinetobacter baumannii (23.6%), and Klebsiella pneumoniae (13.6%). A very high rate of resistance (80-100%) was observed among predominant GNB to ciprofloxacin, ceftazidime, co-trimoxazole, and amoxycillin/clavulanic acid combination. Least resistance was noted to meropenem and doxycycline. CONCLUSION: Nonfermenters are the most common etiological agents of LRTIs in ICU. There is an alarmingly high rate of resistance to cephalosporin and beta-lactam-beta-lactamase inhibitor group of drugs. Meropenem was found to be the most sensitive drug against all GNB. Acinetobacter and Klebsiella spp. showed good sensitivity to doxycycline.