Sclerosing Mesenteritis: A Rare Cause of Abdominal Pain

Sclerosing mesenteritis (SM) is a rare inflammatory fibrotic disease of the small intestine mesenteric fat often discovered incidentally on a CT scan. Clinical manifestations depend on the mass effect on the viscera and vessels. The most common symptoms are abdominal pain, bloating, and nausea. SM occurs predominantly in Caucasian men, during the fifth to seventh decades of life. We present a 69-year-old woman with SM whose symptoms were thought to be from irritable bowel syndrome. A 69-year-old female with a history of fibromyalgia presented with recurrent bouts of abdominal pain across her mid-abdomen lasting 30 minutes to an hour associated with nausea, alternating constipation and diarrhea with occasional mucus, and bloating. She used bismuth subsalicylate and ondansetron with temporary relief. Upper endoscopy and colonoscopy were unrevealing. Initially, she was felt to have irritable bowel. Later she presented with nausea and right upper quadrant pain and underwent cholecystectomy. When her pain recurred, the patient had a CT abdomen and pelvis which showed multiple sub-centimeter mesenteric lymph nodes with surrounding haziness and stranding in the root of the mesentery consistent with SM. The patient had a pannus biopsy showing fat necrosis that confirmed the diagnosis. She continued to have waxing and waning symptoms over several years and in the interim was diagnosed with melanoma limited to the skin. The patient had a particularly severe episode of abdominal pain prompting a repeat CT scan with a subsequent biopsy of an enlarged left para-aortic lymph node that revealed lymphoma. Our patient's diagnosis of SM was delayed as her symptoms were mistaken for irritable bowel syndrome. Worsening symptoms should alert clinicians to an alternate diagnosis such as SM. There are characteristic radiographic findings on CT scans and biopsy of the lesions. SM's association with neoplastic diseases such as lymphoma, melanoma, colorectal, and prostate cancer is controversial, however, practitioners should be aware of this possibility and consider biopsy for any suspicious lesions.