Systemic reactive inflammation by Yersinia pseudotuberculosis

Introduction: Yersinia belongs to the family of enterobacteriaceae. Yersinia pseudotuberculosis is a rare cause of disease in humans but has become of increasing importance. Common manifestations are mesenteric lymphadenitis presenting with symptoms of appendicitis, and inflammation of the terminal ileum with gastrointestinal bleeding and intussusception. A septicemic form of Yersinia pseudotuberculosis infection has been reported only rarely and is seen in patients with underlying disorders (diabetes, hepatic cirrhosis, malignancy, iron overload). More frequently enteritis is followed by immunological post-infectious syndromes such as arthritis and erythema nodosum but not by severe systemic inflammation.

Case report: We report a 13-year old boy, presenting with fever of unknown origin for eight weeks and severe abdominal pain. The fever was high to 40° C all evening. The diagnostic workup revealed peritonitis, abdominal lymphadenopathy (caseating aspect), pseudomembranous colitis, pericarditis with insufficiency of the tricuspidal valve, mikrocytic hypochromic anemia, and splenomegaly. ESR was 120/140, CRP showed a maximum of 150,9mg/l. The immunological parameters were normal. No bacteria could be detected in stool, urine, blood cultures, and in peritoneal fluid and mesenterial lymph nodes. Serotyping revealed high titers of IgG, IgA and IgM for Yersinia pseudotuberculosis. Histologically the lymph node showed epitheloid granulomatosis.

Discussion: The patient's history and the clinical presentation pointed to an acute septicemia based on a focus in the abdomen. The labs and the macroscopic and microscopic findings of the colonoscopy and laparoscopy revealed the diagnosis of a systemic reactive inflammation by Yersinia pseudotuberculosis. After starting a therapy with Trimethoprim-Sulfamethoxazol the patient improved rapidly and the laboratory parameters became normal.

Conclusions: A reactive inflammation by Yersinia pseudotuberculosis is a rare differential diagnosis in case of fever of unknown origin and severe abdominal pain.