Abstract
A previously healthy, a 28-year-old man visited the hospital because of sudden diarrhea and bloody stool. Abdomen was soft and flat. He complained of mild upper abdominal pain, but not nausea or vomiting. Blood results showed neither inflammatory response nor anemia. Arterial phase of computed tomography (CT) scan showed appendiceal hemorrhage. Findings that would indicate acute appendicitis, such as appendix swelling, were not shown in the CT scan. Emergency colonoscopy examination revealed oozing from the appendiceal orifice. We performed a single incision laparoscopic appendectomy on the unexplained appendiceal hemorrhage. Laparoscopic findings revealed the appendix to be normal with no sign of inflammation. We also examined toward the oral side of the terminal ileum, but did not find evidence to doubt a diagnosis of Meckel's diverticulum. The serosa of the specimen was unremarkable. Histopathological diagnosis was acute phlegmonous appendicitis. Histopathological findings showed the growth of capillaries associated with erosion and abscess formation, but did not show any exposure of vessels nor ulceration that would cause arterial hemorrhage. Histopathological examination indicated the cause of appendiceal hemorrhage to be acute appendicitis with erosion. There were no postoperative recurrences, such as bloody stool or progression of anemia. The postoperative course was uneventful, and the patient was discharged on the 4th postoperative day. The causes of melena and bloody stool can vary widely. To our knowledge, bloody stool caused by arterial appendiceal hemorrhage is rare.
