Comparative Study of Campylobacter spp. Isolated from Children With Gastroenteritis in Bahonar Hospital, Karaj, Using PCR and RFLP

Campylobacter species are responsible for the majority of cases of food-borne gastroenteritis. The sources of the disease outbreaks are often contaminated water or milk, and consumption of undercooked poultry product is the main cause of sporadic campylobacteriosis cases.
The aims of this study were to determine the prevalence of Campylobacter gastroenteritis in children and to differentiate the interfering species using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) methods at the Bahonar hospital in Karaj, Iran.
Patients and A total of 150 stool samples were collected from children under 10 years old during the summer of 2014. PCR was performed using genus- and species-specific primers and RFLP was done using AluI and TasI enzymes.
The results showed the amplification of 400 and 491 bp segments and Campylobacter contamination in 30 (20%) samples; 5 out of 30 Campylobacter positive samples (16.66%) were identified as C. jejuni, 20 (66.66%) as C. coli, 3 (10%) as C. jejuni and C. coli (mixed infection), and 2 (6.66%) were identified as non-jejuni, non-coli Campylobacter using the PCR method. Following the evaluation of RFLP results, 7 positive samples (23.33%) showed the electrophoretic pattern of C. jejuni, 21 (70%) showed the electrophoretic pattern of C. coli, and 2 (6.6%) showed both of the patterns and mixed contamination with jejuni and coli species. The results of digestion with TasI did not show any C. lari or C. upsaliensis patterns.
The results of this study showed high percentage of Campylobacter contamination in the tested stool samples. The other surprising finding was the high rate of Campylobacter coli positive samples; the difference between the results of PCR using species-specific primers (hipo and asp) and the RFLP method (electrophoretic patterns) in some of the positive samples confirms the hypothesis of variations in nucleotide sequences of the hipo primer binding site in some Iranian isolates of Campylobacters.