An Unusual Case of Ascites: Multicentric Castleman Disease Associated with Poems Syndrome Presenting as High Saag Ascites

Castleman disease is a rare histopathological entity associated with a variety of lymphoproliferative disorders and autoimmune conditions. The disease can occur in a unicentric form (involving single lymph node group) or multicentric form. While sometimes associated with POEMS syndrome, ascites is not an uncommon association with these disorders. However, the ascites described in association with Castleman disease or POEMS is usually a low SAAG ascites. We report a case with high SAAG ascites as the presenting feature in a patient with POEMS syndrome and multicentric Castleman disease which is quite rare as evidenced by scarcity of literature. Our patient who had presented with ascites, was found to have polyneuropathy, organomegaly (liver and spleen), endocrinopathy (thyroid hormone abnormality), monoclonal gammopathy and skin lesions on evaluation. The scenario was complicated due to a misdiagnosis of tuberculosis from elsewhere and an improper course of antituberculosis treatment. Things fell into place when the diagnosis was confirmed with the histopathological examination of the cervical lymph node biopsy showing hyaline vascular variant of Castleman disease. Thalidomide and its congeners along with steroids have been the mainstay of treatment of this along with stem cell transplantation, while anti IL-6 agents like siltuximab are emerging treatment options. In view of its complexity and the multisystem involvement of this syndrome, it may be easily overlooked or missed if one is not aware or actively looking for the various clinical clues.