Yersinia enterocolitica bacteremia and enterocolitis in a previously healthy 20-month-old girl

Yersinia enterocolitica is a gram-negative bacillus that can cause illness ranging from a self-limiting enterocolitis to life-threatening bacteremia. Y. enterocolitica biotype 1B, serotype O:8 (1B/O:8), is the most pathogenic of the Yersinia species because of the presence of the high-pathogenicity island and the Yersinia virulence plasmid (pYV). Here, we report a pediatric case of Y. enterocolitica 1B/O:8 bacteremia and enterocolitis. A 20-month-old girl was admitted to hospital with fever, pharyngitis, and abdominal pain on day 2. Blood culture on admission was positive for Y. enterocolitica 1B/O:8. Stool culture on day 5 after cefotaxime treatment was also positive for Y. enterocolitica 1B/O:8, but only after cold enrichment at 4°C for 3 weeks. PCR assays identified the pYV only in stool specimens, indicating that strains from routine blood culture at 37°C lacked the pYV. The present case showed the usefulness of stool culture with cold enrichment and agglutination test for the diagnosis of Y. enterocolitica infection. We would therefore like to emphasize the importance of collection and preservation of stool specimens for the identification of pYV. To our knowledge, this is the first reported pediatric case of Y. enterocolitica 1B/O:8 bacteremia.