2571 Unicentric Castleman Disease as a Cause of Ileal Perforation: A Case Report

Abstract

INTRODUCTION: Castleman disease is describes a group of heterogenous lymphoproliferative disorders that share histopathologic features. It is divided into Unicentric castleman disease (UCD) and Multicentric Castleman disease. We present a case of a patient with one year history of recurrent small bowel obstruction (SBO), which was found to be due to UCD affecting the mesentery. CASE DESCRIPTION/METHODS: A 75 years old gentleman initially presented one year ago with an episode of SBO. He had no history of abdominal or pelvic surgery. CT scan showed a transition point near the terminal ileum and mesenteric/retroperitoneal lymphadenopathy. Patient underwent a colonoscopy which showed a stenotic ileocecal valve with active colitis in the terminal ileum and ascending colon suggestive of resolving intestinal ischemia. This time, patient was admitted with decreased oral intake due to SBO. He was found to have a low albumin of 0.8 and an AKI on CKD. He also had bilateral pleural effusions and new ascites. He was treated conservatively initially, but he developed new abdominal pain with X ray showing free air under the diaphragm concerning for intestinal perforation. Patient underwent emergent laparotomy, where he had a perforated terminal ileum and multiple large fibrotic lymph nodes in the associated mesentery. Pathology showed proliferation of atretic follicles. There were occasional penetrating capillaries and the mantle lymphocytes have an onion-skin pattern. The interfollicular zones showed increased plasma cells, but not prominent vascular proliferation. CD3 and CD20 stains showed an intact immune-architecture. The overall findings showed a mixed pattern of Castleman lymphadenopathy, with some features of both the hyaline vascular and plasma cell variants. He had IgA of 510 mg/dl and an abnormal SPEP with IgG lambda paraprotein of 0.39 g/dl. His hospital course was complicated by septic shock due to bacterial and fungal peritonitis. Patient eventually went into cardiac arrest and died. DISCUSSION: Mixed variant CD is mostly multicentric, however, some patients with UCD reveal features of both hyaline vascular type and plasma cell type. In this case, apart from abdominal pain and recurrent SBO episodes, there were no other complaints. Acute phase reactants, CBC, and serological testing for HIV, HHV-8, Hepatitis B, Hepatitis C, RPR and PPD were all unremarkable. UCD is usually asymptomatic and generally curable using surgical resection but in this case led to severe complication ending in patient's demise.