The Frequency of Infection with Campylobacter, Its Species Diversity, and Antimicrobial Resistance in Stool Samples of Patients with Community-Acquired Gastroenteritis in Tehran

Campylobacter species are among foodborne pathogens that are known as the main cause of inflammatory diarrhea in humans. In this cross-sectional study, we investigated the prevalence of Campylobacter spp. and their drug resistance status in fecal samples of patients with community-acquired gastroenteritis in Tehran.

In this survey, infection with Campylobacter spp. was evaluated in 400 stool samples of patients with diarrhea. Accordingly, microscopic examination to show the presence of exudative diarrhea, rejection of fungi and parasitic infections, enrichment and culture in a specific medium under microaerophilic conditions, determination of biochemical identity, and molecular confirmation at genus and species levels for C. jejuni, C. coli, C. lari, and C. upsaliensis were performed. Antibiotic resistance patterns were determined by E-test and disk diffusion methods, and the presence of the dominant gyrA gene mutations in the quinolone-resistance domain of C. jejuni isolates was determined by using Mismatch Amplification Mutation Assay-polymerase chain reaction (MAMA-PCR)[1].

A total of 28 strains of Campylobacter were isolated from the samples obtained from the patients with diarrhea. The most common species were C. jejuni (6%), C. coli (0.5%), C. lari (0.25%), and other unknown species (0.25%). The highest antibiotic resistance rate was observed against tetracycline and ampicillin (53.5% and 50%, respectively), and the lowest rate was detected for nalidixic acid and ciprofloxacin (28.5% and 28.5%). Multiple drug resistance (MDR) phenotype was detected among 51.8% of the strains.

Results of this study indicated C. jejuni as the main Campylobacter species responsible for community-acquired diarrhea among the studied patients. The high rate of resistance to antibiotics and MDR phenotype in these strains compared with other countries is considered a risk, especially in the treatment of invasive infections.