A 6-month study of infections and antibiotic resistance pattern in a Greek intensive care unit

Introduction

Severe infections and resistance of microorganisms to broad-spectrum antibiotics constitute a major concern for ICU physicians. Our purpose was to record the microorganisms usually responsible for infections in our ICU and their pattern of resistance to antibiotics during a 6-month period.

Patients and methods

We performed a prospective study between 1 June 2003 and 1 December 2003, including all patients hospitalized for more than 48 hours. Infections presented during this period were recorded as well as the sensitivity of microorganisms to special antimicrobial agents.

Results

A total of 65 patients were included in the study (53 men, 12 women) with a mean age of 54.6 years. The mean ICU stay was 24 days. One hundred and fifty-one infections were recorded: ventilator-associated pneumonia (62.3%), primary bacteremias (22.5%), catheter-related infections (9.4%), meningitis (1.3%) and surgical infections (2%). Microorganisms most commonly isolated were: Pseudomonas aeruginosa (33.7%), Acinetobacter baumannii (28.5%), Klebsiella pneumoniae (14%), and Staphylococcus epidermidis (7.8%). Patterns of resistance were as follows: P. aeruginosa was sensitive to ceftazidime in 16.7% of cases, to imipenem in 38.4%, to ciprofloxacin in 10.2% to piperacillin/tazobactam in 62.8% and to colistin in 98.7%. A. baumannii was sensitive to imipenem in 61% of cases, to ampicillin/sulbactam in 51.5% and to colistin in 76.5%. K. pneumoniae was sensitive to imipenem in 74% of cases, to piperacillin/tazobactam in 48% of cases and to colistin in 88.8%.

Conclusion

Significant resistance of Gram-negative microorganisms to broad-spectrum antibiotics is noticed, posing important therapeutic problems. Change of antibiotic policy and strict hand hygiene are some of the measures that could possibly help us face this ominous situation.