Epidemiology and Antimicrobial Resistance of Enteric Pathogens in Dhahira Region, Oman

Background: We reviewed the monthly laboratory surveillance reports and hospital laboratory database in Dhahira region, Oman. Methods: All patients for whom a stool sample examination request was made from 1st January 2002 to 31st December 2006 (5 years) were included in the study. Antimicrobial resistance pattern was studied for 2 years period. The cultures were done using standard laboratory procedures and antibiotic sensitivity by Kirby Bauer disc diffusion method. Results: Of the 85,210 stool samples examined, 18% showed positive result for one or more parasitic infection. The most common were E. hystolytica (7.1%), Giardia (7.9%) and E. coli (1.9%). A total of 7,830 cultures were done, among them 11.4% showed positive result for bacterial pathogen. The most common were Salmonella (5.8%) and Shigella species (4.4%). The antimicrobial susceptibility patterns of 265 bacterial pathogens were analyzed. Of the Shigella strains, 71.8% were resistant to trimethoprim/sulphamethoxazole (SXT) and 39.4% to ampicillin and 32.4% to tetracycline. Salmonella and E. coli strains were frequently resistant to ampicillin (12.5% and 47.7%, respectively) Conclusion: This study provides important information on the prevalence and antimicrobial resistance pattern of enteric pathogens in Dhahira region population. SXT, ampicillin, and tetracycline are the drugs commonly associated with resistance.