Objective Intensive care unit (ICU) acquired infections bring some degree of morbidity and mortality to the ICU patients. In this study the prevalent bacterial infections among ICU patients in two major university hospitals in Shiraz was investigated.

Methods A cross sectional prevalence study was performed on all the patients hospitalized longer than 48 hours in a total of 8 intensive care units at two Shiraz University teaching hospitals. Samples were microbiologically cultured. Rates of infection and death, microbiological isolates and their resistance profile to most commonly available antibiotics were detected.

Results 123 specimens from 89 patients aged 1 month to 80 years (38.3±13.4) were studied. 46 patients (51.7%, 95% CI 41.3 to 62.1%) showed infection based on culture and clinical finding. 43 patients (48.3%) had no defined type. 37 patients (41.6%) had more than one, and 9 patients (10.1%) had only one ICU-related nosocomial infections. The overall mortality rate for ICU acquired infections was 10.9% (5 patients) and bacteria with gram-negative microorganisms was the cause of death. Gram negative bacteria were significantly more involved in infections than Gram-positive bacteria (p<0.05). The most frequently reported infections were urinary tract (84.7%), respiratory tract (65.2%), wound (32.6%), and blood (23.8%). The most frequently isolated bacteria was Pseudomonas (39.1%) which was mainly sensitive to amikacin and ceftazidme.

Conclusion The potential effects of such rates of ICU infection and the outcomes emphasize the importance of specific measures for infection control in critically ill patients in ICUs, especially when using urinary catheters.