Idiopathic Myointimal Hyperplasia of the Mesenteric Veins Diagnosed Preoperatively.

Idiopathic myointimal hyperplasia of the mesenteric veins (IMHMV) of the colon is a very rare disease that in previously reported cases was often mistaken for inflammatory bowel disease because of similar clinical characteristics. In our review of the literature, we found a total of 15 cases described, generally featuring sigmoid and rectal colitis and symptoms of abdominal pain, diarrhea, and hematochezia refractory to treatment with immunosuppressants. In all previously reported cases, the diagnosis was achieved only after surgical resection of the affected area. Herein, we report a case of IMHMV that was diagnosed preoperatively based on clinical information and endoscopy with biopsies. This led to the withdrawal of immunosuppression before a carefully planned surgical resection, with confirmation of the diagnosis in the resected tissue. To our knowledge, our case of IMHMV is the first to be diagnosed preoperatively.