[Two cases of Yersinia pseudotuberculosis infection in children]

Yersinia pseudotuberculosis (Y. pseudotuberculosis) infection is an intestinal infectious disease comparable in importance as those with Campylobacter or Salmonella. Clinical symptoms of Y. pseudotuberculosis infection vary. In this report, we will describe the clinical symptoms and immunological conditions of the patients with Y. pseudotuberculosis infection, including 2 or our own cases. Case 1 was a 4 years old male infant admitted to the hospital with major complaints of fever, diarrhea, and vomiting. Kawasaki disease was the most suspected diagnosis from the clinical viewpoint. These symptoms improved by symptomatic treatments. Serum examination during hospitalisation revealed the infection of Y. pseudotuberculosis 4a. Case 2 was a 7 months old male baby with psychomotor developmental delay. The patient was admitted to hospital with major complaints of fever and eruptions. The patient was diagnosed to have a severe infectious disorder based on the clinical symptoms and findings of laboratory tests. Treatments with antibiotics improved the conditions. Serum examination during hospitalisation also revealed the Y. pseudotuberculosis 5a infection. Both of these cases showed decreased cellular immunity during the acute phase of the infection which was normalized with the improvement in clinical conditions. It was thus suggested that Y. pseudotuberculosis had a possibility to influence the cellular immunity of hosts transiently but significantly.