Profound Hypogammaglobulinemia 7 Years after Treatment for Indolent Lymphoma

We report a case of a previously healthy 31 year old woman diagnosed with Stage IIIA follicular lymphoma treated with fludarabine in combination with cyclophosphamide and rituximab who presented seven years after the completion of therapy with CD4 count depression, panhypogammaglobulinema and a history of recurrent sinus infections. We performed comprehensive immunophenotypic analysis and found her to have only 1.2% switched (normal 21 +/- 8%) and 4.7% non-switched (11 +/- 4%) memory B cells with 92% of B cells belonging to the naïve compartment. We have previously evaluated reconstitution of the B cell compartment during the 6 to 12 month recovery period after treatment with rituximab and found a similar immunophenotypic pattern. In our patient, this defect was observed seven years after the administration of rituximab in combination with an alkylating agent and purine analog. The patient was started on monthly intravenous immunoglobulin treatments with complete resolution of her symptoms.