Small Bowel Obstruction Caused by Peritoneal Immunoglobulin G4-Related Disease Mimicking Carcinomatosis: Case Report
A 57-year-old female presented with a several-year history of unexplained dyspeptic symptoms. Numerous vague causes were suggested including oesophagitis due to a small hiatal hernia and treated with lansoprazole and dysfunction of the sphincter of Oddi on the basis of a hepato-biliary scintigraphy (data not shown).\nDuring the past year, the patient had experienced three acute episodes characterized by hypogastric colic pain followed colickly pain followed by alimentary-but occasionaly fecaloid-vomiting. These episodes lasted for about 24 to 48 hours and ended by diarrheal debacle. During the last episode, the patient was admitted to the emergency room after the ending diarrheal debacle. Laboratory tests and abdominal plain film were normal at this time. A new episode of abdominal pain compelled the patient to get readmitted to the emergency room. The pain was increasing for a period of 24 hours. The patient remained apyretic. On physical examination, the abdomen was distended. On palpation, there was diffuse tenderness especially in the right iliac fossa. Auscultation revealed a metallic sound. Laboratory test results indicated a mild inflammation with a CRP level of 5.84 mg/L (normal value: < 5 mg/L) and a white blood cell count of 16200 units.\nContrast-enhanced abdominal multidetector-row computed tomography () revealed a subocclusive intestinal syndrome. The middle and distal small bowel loops were distended along with the presence of hydroaeric levels. The transitional level was found within the pelvic area, and the origin seemed to be related to diffuse peritoneal carcinomatosis including pelvic masses and nodules diffusely covering and encasing the gynecological structures, the terminal ileum and the pelvic folds. A small amount of ascites was present. Numerous smaller nodules were scattered in the hypogastrium and in both iliac fossae. Some nodules were partially calcified and moderately enhanced on delayed contrast-enhanced CT scan. A possible ovarian origin was considered. The option of an emergency surgery was chosen to treat the subocclusive intestinal syndrome. An extensive surgical procedure was performed at one time including total radical hysterectomy, debulking, omentectomy, and resection of the ileo-cecal junction with resection of more than 30 centimeters of the terminal ileum.\nGross anatomy () showed numerous whitish nodules which extensively covered and invaded the gynecologic structures, the wall of the ileum and the mesenteric fat tissue. The pattern of invasion was that of diffuse carcinomatosis. On sections, some of these nodules were found to deeply penetrate the entire bowel wall from the serosa to the mucosa ().\nMicroscopically (), these nodules showed areas of dense storiform fibrosis separated by areas of dense lymphoplasmacytic inflammatory infiltrate containing numerous normal plasma cells. Typical mild to moderate eosinophilia, germinal center formation and obliterative phlebitis were also detected. IgG4 immunostaining showed numerous IgG4-positive plasma cells.\nThe final diagnosis was IgG4-RD with a predominant but a very unusual peritoneal involvement. The serum IgG4 level was not assessed in the preoperative period, but it was found to be normal in the postoperative and follow-up periods.\nThe patient was treated by methylprednisolone with an initial dose of 32 mg per day. This dose was reduced in a stepwise manner to 12 mg per day. Due to persistent small peritoneal nodules in the right iliac fossa and in the pouch of Douglas after six months (data not shown), azathioprine at a dose of 100 mg daily was added. Concomitantly, the dose of methylprednisolone was gradually lowered to 2 mg per day. At one year of evolution, the remaining small nodules were stable (data not shown).