Cholecystitis caused by infiltration of immature myeloid cells: a case report.

A 59-year-old man with myelodysplastic syndrome who was hospitalized for evaluation of fever and generalized fatigue had elevated levels of C-reactive protein and pancytopenia. A search for a site of infection and empiric treatment with antibiotics were unsuccessful. Over 5 to 6 weeks right upper quadrant pain and rebound tenderness developed. Sonographic Murphys sign was present. Computed tomography showed thickening of the gallbladder wall, and repeated ultrasonography demonstrated changes consistent with cholecystitis. Open cholecystectomy was performed as an emergency procedure. Macroscopically the resected gallbladder showed an edematous and thickened wall. Histopathologic examination revealed transmural infiltration by atypical mononuclear cells with distinct nuclei. The cells showed immunohistochemical staining for CD15, indicating myeloid lineage. By 10 days after surgery, counts of leukocytes and leukoblasts had markedly increased, reaching 36,700/microL and 76.0%, respectively. The blast crisis was thought to indicate progression from myelodysplastic syndrome to leukemia. The patient died of progressive disease 12 days after surgery. We have described a rare case of acute cholecystitis caused by infiltration of immature myeloid cells to the gallbladder. An acute abdomen complicating hematologic disorders is life-threatening and requires prompt and appropriate treatment.