Spontaneous rupture of the spleen caused by a Bacillus infection: report of a case.

We report a case of spontaneous splenic rupture (SSR) caused by a Bacillus species (sp.) infection. A 36-year-old man on warfarin therapy since an aortic valve replacement at the age of 13 was admitted to our hospital with a 3-week history of a high fever. He had been asymptomatic until 4 months previously, when he suffered a cerebral embolism despite adequate oral anticoagulation. Abdominal computed tomography revealed splenic infarctions, which resulted in splenic rupture 2 days later. After embolization of the splenic artery, splenectomy was successfully performed. Pathologic examination revealed splenic infarction, resulting from septic emboli, with associated rupture of the splenic capsule, but no abscess was found. Bacillus sp. was isolated from cultures of arterial blood preoperatively, and the excised splenic specimens, postoperatively. In addition to rupture of the suppurating intrasplenic vessels with hematoma formation, the anticoagulant therapy possibly contributed to distension of the intrasplenic hematoma.