Abstract
Pyogenic granuloma (PG) represents a lobular capillary proliferation commonly seen in the skin or oral mucosa. They are rarely reported in the gastrointestinal tract. The mechanism underlying PG pathogenesis is not well understood. Only one case of cutaneous PG associated with cytomegalovirus (CMV) infection has been reported in the English literature. Here, we report such a unique case of PG arising from the small bowel. A 67-year-old male, status post ileocolic resection, presented for follow-up colonoscopy because of Crohn's disease of the terminal ileum and the colon. Colonoscopy revealed inflammation at the ileocolic anastomosis as well as an 8-mm pedunculated lesion with an irregular surface in the neo-terminal ileum. Histological studies of the small bowel mucosa revealed chronic active ileitis with pyloric gland metaplasia, consistent with his clinical history of Crohn's disease. The lesion demonstrated a lobular architecture consisting of clusters of small capillaries of various sizes lined by a single layer of cytologically bland endothelial cells, and accompanied by acute and chronic inflammatory infiltrates and surface erosion/ulceration. The histological features supported the diagnosis of PG. Scattered viral inclusions with positive CMV immunoreactivity were present in the endothelial cells and glandular cells of pyloric gland metaplasia within the PG. To the best of our knowledge, this is the first documented case of PG with local CMV infection in patients with inflammatory bowel disease.