[Case of subcutaneous and mesenteric acute panniculitis with Sjögren's syndrome]

We report a case of a 27-year-old Japanese female with Sjogren's syndrome (SS), who suffered from several episodes of subcutaneous and mesenteric panniculitis with a recurrence within one year. After a history of fever and skin rash, the patient underwent surgery at a local hospital with a diagnosis of acute appendicitis complicated with an ileocecal abscess. She was also diagnosed as having SS. After the operation, the fever and skin rash persisted. She was treated with prednisolone (PSL), and her symptoms resolved. A recurrent bout of abdominal pain with fever, annular erythema on the trunk and a nodular erythematous rash on the lower extremities occurred six months after the operation. A skin biopsy from the lower extremities showed findings that were compatible with panniculitis. Abdominal computer tomography (CT) showed a diffuse swelling with soft tissue density in the intestinal mesenterium and para aortic area. A retrospective examination of the operative specimen obtained from the local hospital revealed centrilobular infiltration of neutrophils in the mesenteric adipose tissue with fat necrosis, which is compatible with mesenteric panniculitis. Twenty mg/day of PSL was successful in treating the systemic panniculitis, and the abnormal diffuse soft tissue density on the abdominal CT disappeared after three weeks of PSL administration. Systemic panniculitis is a rare complication in SS, and the pathogenesis is unclear.