Intramural Hematoma Causing Complete Colonic Obstruction: 1165

Purpose: Intramural hematomas are a rare cause of colonic obstruction, usually associated with trauma or coagulopathy. We present a case of intramural hematoma in a patient with AL amyloidosis. A 57-year-old man with a history of AL amyloidosis with cardiac, hepatic and soft tissue involvement presented with LLQ abdominal pain and diarrhea. Shortly after admission, he ceased having any bowel movements and could not pass flatus. His physical exam was notable for a markedly distended and tympanitic abdomen with tenderness to palpation in the LLQ, without rebound or guarding. Laboratory values were unchanged from baseline. A plain abdominal radiograph revealed a transition point at the splenic flexure concerning for colonic obstruction. Abdominal CT scan revealed a 9 × 8 × 18 cm obstructing mass in the splenic flexure with dilation of the proximal transverse colon. Based on Houndsfield units, there was concern that the mass was a hematoma. Other considerations, such as a plasmacytoma or adenocarcinoma were less likely. The patient underwent exploratory laparotomy and diverting colostomy leaving the mass in situ given his tenuous status. The post-operative course was complicated by multi-organ system failure and the patient expired on POD #1. Autopsy revealed hemoperitoneum and the intramural hematoma. Histology showed extensive amyloid deposition in all blood vessels of the colon. Intramural hematomas are a rare cause of colonic obstruction with only 30 cases of colonic hematomas reported in the literature since 1950. Amyloidosis predisposes patients to bleeding secondary to coagulopathy or amyloid angiopathy, but still rarely leads to colonic hematoma formation. Patients present with typical bowel obstructive symptoms. Prognosis depends on patients' physiologic reserve.Figure: Axial image of hematoma at the splenic flexure.Figure: [1165] Gross specimen, autopsy.