Castleman's disease--a rare disease with varying presentation

Castleman's disease is a relatively rare immunoproliferative disease primarily involving the lymph nodes. It occurs in two forms- unicentric and multicentric. Though it is a benign disorder the multicentric form can be difficult to treat and can have a poor prognosis. The treatment is often delayed as its differential diagnosis includes several common diseases including lymphoma, benign and malignant lymph node mass, thymoma, rheumatoid nodules. It is at times associated with pemphigus vulgaris as a paraneoplastic syndrome as has occurred in one of the cases. This makes the diagnosis even more difficult as the patients generally undergo a prolonged treatment initially for the associated condition without significant improvement. Three such cases were encountered in the last three years, all of which occurred in relatively young patients and caused great diagnostic dilemma. They responded well to treatment and are currently doing well in follow-up. This disease though rare should be considered in the differential diagnosis of lymphoma, reactive nodular hyperplasia, malignant lymph node enlargement. It is also important to rule out this disease in the diagnosis of treatment-refractory cases of pemphigus vulgaris.