Multidrug-resistant bacteria isolated from intensive-care-unit patient samples

ABSTRACT

We examined epidemiological aspects and bacterial resistance patterns of bacteria isolated from intensive care unit (ICU) patient samples. During a 10 month period (from June 2006 to March 2007), 812 samples of blood, urine and cerebral spinal fluid (CSF) from 553 hospitalized patients, in ICU wards, including pediatric surgical, neonatal, adult surgical I, adult surgical II, general pediatrics, neurosurgical I, neurosurgical II, and internal medical, were collected. Minimum inhibitory concentration (MIC) of antibiotics for bacteria isolates was determined by the E-test method. The internal medicine ICU with 28.7 percent admissions gave the largest contribution. Coagulase negative staphylococci at frequencies of 66.7 percent and 36.5 percent and E. coli at 20.9 percent were the bacteria most frequently isolated from the blood, CSF and urine samples, respectively. Samples taken from patients 20-40 years old were the most frequent (32.2 percent), while the group of patients over sixty years contributed least (18.5 percent). Both Gram-positive and - negative isolates expressed resistance to most of the penicillins and cephalosporins tested. Combined therapy with vancomycin and meropenem or imipenem gave the most effective treatment against Gram-positive and Gram-negative isolates based on empirical therapy. High frequencies of multiresistant bacteria in ICUs warn us to administer a few effective antibiotics in our hospitals more wisely in order to reduce selective pressure on sensitive strains. This could help save the life of ICU patients and prevent of spread of resistant isolates in these critical wards. Due to continuous changes in antibacterial susceptibility patterns, periodical antibacterial sensitivity assessment in ICUs should be mandatory.