Inflammatory Pseudotumor of Omentum Containing Gas Misdiagnosed as Perforation of Hollow Organs

Abstract BackgroundInflammatory pseudotumors that grow on the omentum are relatively rare, and inflammatory pseudotumor most often involves the lung. As far as we know, the inflammatory pseudotumor of omentum, which is in the shape of beaded vesicles and contains gas, has never been reported in the literature. Case presentationwe report a 45-year-old Chinese woman who complained of epigastric pain with hematemesis for 9 hours, physical examination showed subxiphoid tenderness, previous history of gastric ulcer and repair of gastric perforation, laboratory examination showed slight increase of white blood cells and decrease of hemoglobin. Computed tomography showed dotted free gas in the abdominal cavity, and the perforation of the hollow organs was considered. The pathological results after emergency operation showed that histiocyte aggregation with multinucleated giant cell reaction could be seen in the omental tissue. Immunohistochemistry :ER (-), PR (-), PAX-8 (-), CK (mesothelial+), MC (mesothelial+), CR (mesothelial+), CD68 (histiocyte+), SMA (smooth muscle+). The abdominal pain was relieved after surgical resection of the tumor, and recovered well after symptomatic treatment.ConclusionInflammatory pseudotumor of omentum containing gas is easily diagnosed as perforation of hollow organs, with few clinical manifestations of acute abdomen, mostly non-specific, and a good prognosis. Understanding its clinicopathological features and pathological examination methods are helpful to diagnose the disease, so as to choose an appropriate treatment plan, and whether surgical treatment is better than conservative treatment remains to be further studied. The disease should be distinguished from perforation of hollow organs, but the source of gas is unknown. It may have something to do with past medical history.