Acute Myeloid Sarcoma: An Unusual Cause of Diarrhea.

A 62-year-old man with a past medical history of hypothyroidism was admitted for diarrhea and abdominal pain for three weeks. Initial workup for diarrhea was negative. His condition deteriorated after hospitalization. He underwent sigmoidoscopy which showed rectosigmoid mucosal ulceration. Pathology showed leukemic cells infiltration of the mucosa. The patient underwent bone marrow biopsy which confirmed the diagnosis of acute myeloid leukemia (AML). He received induction chemotherapy and his symptoms improved.