[A pseudotumoral lesion revealing Meckel's diverticulum].

INTRODUCTION: Meckel's diverticulum is a common malformation in children, usually asymptomatic, with complications in only 20% of cases. Exceptionally, a tumor can develop in Meckel's diverticulum in children, particularly Burkitt's lymphoma; in adults it can develop into a gastrointestinal stromal tumor, a leiomyosarcoma, or a neuroendocrine tumor such as a carcinoid tumor. The diagnosis of inflammatory pseudotumor following an insidious perforation is rare.

OBSERVATION: We report the case of a 14-month-old boy who presented with fever, asthenia, food refusal, and digestive complaints such as vomiting and tender abdomen suggesting appendicitis. Computed tomography showed an ileal mass of 3cm in diameter, which led to the suspicion of Burkitt's lymphoma. Laparoscopy showed Meckel's diverticulum with a mass of 3×2.8×2cm. Histological examination confirmed the diagnosis of Meckel's diverticulum with gastric heterotopia and showed a proliferation of spindle cells in a myxoid background, with an inflammatory infiltrate made of lymphocytes and plasmocytes. Immunostaining ruled out a malignant tumor. The diagnosis of an inflammatory pseudotumor developing on a Meckel diverticulum with gastric heterotopias was made. The outcome was favorable after surgical resection.

CONCLUSION: While perforation of a Meckel diverticulum with gastric heterotopia is a common finding, the discovery of an inflammatory pseudotumor following a perforation is rare; the differential diagnosis should include Burkitt's lymphoma.