A Rare Cause of Massive Hematochezia: Arteriovenous Malformation of the Appendix

CASE REPORT

A 53-year-old man presented with shortness of breath. He was found to have a hemoglobin level of 3.0 g/dL. He reported multiple episodes of hematochezia for few weeks.

He had a history of iron deficiency anemia and had undergone esophagogastroduodenoscopy and colonoscopy for hematochezia 1 year ago. A computed tomography angiogram did not reveal any active source of gastrointestinal bleeding. Esophagogastroduodenoscopy was normal and colonoscopy showed an arteriovenous malformation (AVM) in the transverse colon, which was treated with argon plasma coagulation.

Colonoscopy this time revealed old blood clots in the entire colon (Figure 1). No more bleeding lesion was seen in the rest of the large bowel. After aggressive cleaning, active bleeding was noted from the appendiceal orifice (AO) (Figure 1). Three cc 1:1,000 epinephrine was injected at the base of the AO. However, this was unsuccessful in achieving hemostasis. Blood kept emanating from the AO, and it seemed that bleeding was arising from within the appendix. The terminal ileum was unremarkable (Figure 1). The patient underwent an urgent appendectomy. Pathology revealed AVM of the appendix. The wall of the appendix shows vascular proliferation with marked congestion (Figure 1).

Figure 1.

Colonoscopy showing (A) large old blood clots in the colon, (B) active appendiceal orifice bleeding, (C) unremarkable terminal ileum, and (D) pathology findings consistent with an arteriovenous malformation.

Acute bleeding from the appendix is one of the least common causes of lower gastrointestinal bleeding. Reported causes include diverticulum, acute appendicitis, AVM, appendiceal neoplasms, ulcer, and erosion. It is critical to perform an urgent colonoscopy with optimal bowel prep to identify the location during the acute occurrence, leading to appendectomy in a timely manner.

DISCLOSURES

Author contributions: F. Khan wrote the article and is the article guarantor. S. Lu provided the pathology images. D. Parajuli revised the manuscript for intellectual content.

Financial disclosure: None to report.

Informed consent was obtained for this case report.