Abstract
Background and Objectives: Incidence of Y. enterocolitica has been increased in the world and several studies have proposed relation between Y. enterocolitica infection and acute diarrhea in children. In this study rate of Y. enterocolitica emergence in children under14 years old and role of some interventional factors including: age and season were investigated. The efficiency rate of KOH and cold enrichment methods and resistant pattern of Y. enterocolitica were also studied.
Materials and Methods: Five hundred diarrheic specimens collected from children under 14 years old (in case of infants rectal swab were used) who were referred to microbiology laboratory of children medical center of Emam hospital in Tehran (1381) and were cultured on selective media for Y. enterocolitica, Shigella spp., pathogenic E. coli and Salmonella spp. In order to increase rate of Y. enterocolitica isolation, samples were enriched at cold (4 ˚ C) and KOH prior to cultivation in selective media.
Results: Six strains of Y. enterocolitica serotype O: 3 were isolated from 500 diarrheic specimens of children under 14 years old. In addition to Y. entercocolitica other enteropathogenic bacteria including Shigella spp. in 36 cases, enteropathogenic E. coli in 26 cases and Salmonella spp. in 12 cases were isolated. All of the Y. enterocolitica positive specimens showed many leukocytes and in 4 cases associated with red blood cells. Clinical manifestations included: diarrhea, abdominal pain and vomiting in all of patients and fever in two of the cases were recorded. Isolated strains of Y. enterolitica were sensitive to aminoglycosids, cotrimoxazole, ceftizoxim and resistant to ampicillin, cefazolin and cephalothin.
Conclusion: Isolation rate of Y. enterolitica increased using enrichment in 4 ˚ C and KOH. The rate of Y. enterocolitica isolation was not as high as other enteropathgens and showed association with seasons and age.