Acute abdomen caused by an infected mesenteric cyst in the ascending colon: a case report.

Mesenteric cysts are rare intra-abdominal tumors. Mesenteric cysts are usually asymptomatic and are incidentally detected during physical or radiological examination. Although uncommon, complications such as infection, bleeding, torsion, rupture and intestinal obstruction cause an acute abdomen. Spontaneous infection is a very rare complication. We present a case of infected mesenteric cysts in the ascending colon, which caused an acute abdomen. A 26-year-old woman was admitted to our hospital with acute abdominal pain. She had a painful mass in the right abdomen on physical examination. Abdominal computed tomography showed a hypodense cystic mass with septation at the mesenteric region of the ascending colon. A laparotomy revealed two cystic tumors at the mesenteric region of the ascending colon. She underwent a right hemicolectomy. The two cysts were filled with a yellowish turbid fluid. The walls of both two cysts were lined with a thin fibrotic membrane without any epithelial cell. They were diagnosed as psuedocysts with E. coli infection. Mesenferic cysts may cause life-threatening complications. Mesenteric cyst, even if it is asymptomatic and was diagnosed incidentally, should be removed completely.