RESUMO
A 5-year-old boy presented with the history of a small lower abdominal swelling since childhood which increased in size and became painful following a fall. Examination revealed a mobile, globular, cystic intraabdominal mass in the lower abdomen. Ultrasonography of the abdomen suggested a 7.5 × 5.5 cm cystic lesion, separate from the bladder, containing an echogenic mobile mass. Intra venous urography excluded any abnormality of the kidneys, ureters and bladder. Exploratory laparotomy revealed a sigmoid mesenteric cyst protruding out of one of the mesenteric leaves and attached to it by a narrow stalk. The excised cyst was found to be thin walled and unilocular. It was internally lined with fibrinous exhudate and contained serous fluid and a solid spherical blood clot. The child had an uneventful postoperative recovery. Histopathology of the cyst wall showed maturing granulation and fibrous tissue with hemosiderin laden macrophages and lymphoid aggregates consistent with the diagnosis of a lymphagioma with chronic inflammatory changes and evidence of past hemorrhage.