Acute colonic intramural hematoma: a rare complication of colonoscopy.

A 74-year-old man with a medical history of chronic renal failure and congestive heart failure underwent diagnostic colonoscopy following a positive fecal occult blood test. He was given oral antiplatelet medications including aspirin (100mg/ day) and sarpogrelate hydrochloride (100mg/day), which were stopped 5 days before colonoscopy. During the procedure, difficulty was encountered in reaching the ileocecal valve because of a redundant tortuous sigmoid colon, and the procedure took approximately 1 hour. On withdrawal of the colonoscope, a bright-red, hyperemic, elevatedmasswith some oozing blood was identified in the sigmoid colon, although no abnormalities had been detected on insertion. The colonic lumen was occupied by the mass, the surface of which was smooth and covered with normal colonic mucosa (●" Fig.1). Urgent abdominal computed tomography (CT) showed a soft tissue mass of the sigmoid colon with a density suggesting blood (●" Fig.2). There was no evidence of free air. On the basis of these findings, a diagnosis of colonic intramural hematoma was made. As the patient’s condition was stable, he was treated conservatively with observation. Three days later, follow-up colonoscopy showed that the hematoma had ruptured and disappeared, having reverted spontaneously back to flat mucosa (●" Fig.3). The patient was discharged home 5 days later free of symptoms. Colonoscopy is a relatively safe procedure, and themost common complications such as bleeding and perforation are rare [1]. In our patient, excessive intraluminal pressure on the sigmoid colon caused by insertion of the colonoscope may have led to injury of intramural vessels. Colonic intramural hematoma is an extremely rare complication of diagnostic colonoscopy and has been described in only two cases [2,3], both of which were detected by CT within the first 12 hours after colonoscopy. To the best of our knowledge, ours is the first case diagnosed as colonic intramural hematoma during colonoscopy.