Antimicrobial resistance of Salmonella and Shigella spp. isolated from blood and feces samples

Abstract

The present study was performed to contribute to the constitution of treatment protocols and to the follow up of future resistance development by determining antibiotic susceptibilities, the presence of extended spectrum beta lactamase and antimicrobial resistance rates in 21 Salmonella and 31 Shigella spp. isolated from feces samples and 30 Salmonella spp. isolated from blood samples at our bacteriology laboratory between 2001 and 2004. Antimicrobial susceptibilities were determined by using Kirby-Bauer disc diffusion method according to the criteria of Clinical and Laboratory Standards Instute, 2005. Resistance rates in Shigella isolates for trimethoprim/sulphamethoxazole and tetracycline were 71% and for amoxycillin/ clavulanic acid was 9.7%. In Salmonella isolates from feces samples, resistance rates for ceftazidime, cefotaxime, trimethoprim/sulphamethoxazole and gentamicin were 4.8%, 9.5% for amoxycillin/clavulanic acid, and 33.3% for tetracycline. In Salmonella isolates from blood samples resistance rates were 50.0% for ampicillin, 20.0% for nalidixic acid, 10.0% for amoxycillin/clavulanic acid, and 6.7% for chloramphenicol, cefotaxime, trimethoprim/sulphamethoxazole, and 3.3% for gentamicin, tetracycline, ceftazidime, and piperasillin-tazobactam. There was no extended spectrum beta lactamase in isolates studied. Although there was no resistance for kinolons that have been frequently used instead of other antibiotics in treatment protocols recently, a clinical treatment failure risk should be kept in mind considering the resistance rate of 20.0% for nalidixic acid.