Distribution of sulfamethoxazole trimethoprim constin in Vibrio cholerae isolated from patients and environment in Iran

The occurrence of drug-resistant Vibrio cholerae is being reported with increasing frequency worldwide. Spread of resistant strains has been attributed, in part, sulfamethoxazole trimethoprimconstin (SXT-C). Sixty V. cholerae isolates obtained from cholera patients from different provinces in Iran during 2004 to 2006 and thirty-seven V. cholerae strains from surface water sources at 5 different locations in Tehran, Iran during 2006 were subjected to antibiotic susceptibility testing and polymerase chain reaction amplification of SXT-C. In clinical isolates the highest and the least levels of antibiotic resistance were seen to SXT, streptomycin and chloramphenicol (95, 95 and 92%, respectively) and doxycycline, gentamicin and oxytetracycline (0, 3 and 3%, respectively). PCR for SXT element of clinical and environmental isolates was positive for 95 and 19% of isolates, respectively. The results of this study showed that among the clinical and environmental V. cholerae resistance to SXT, streptomycin and chloramphenicol could be, in part, due to wide distribution of SXT-C isolates.