68:
Clinical Diagnostic Difficulties of Post-Rituximab Secondary Immunodeficiency Prior to the Onset of Long Term Complications
Saturday, March 3, 2018
South Hall A2 (Convention Center)
Jeehyun Katie Rha, MD, Elise Loughman, BS, Marissa A. Love, MD, Selina A. Gierer, DO FAAAAI
RATIONALE:

Rituximab, an anti-CD20 antibody widely used in the treatment of B cell lymphoma and rheumatologic diseases, depletes a large portion of B cells, whose main function is to produce antibody. Our proposed retrospective research reviewed charts of patients’ post-rituximab therapy for lymphoma to identify if they had primary versus secondary immunodeficiency, given Rituximab may complicate the diagnosis as to whether the patient had a primary or secondary immunodeficiency. A universal protocol for long-term follow up has yet to be developed.

METHODS:

Retrospective case study of 10 patients with a history of hypogammaglobulinemia status-post rituximab therapy was completed. We reviewed the complications that ensued from this disease state, follow-up, and treatment regimens post diagnosis.

RESULTS:

We identified a number of patients who suffered from common complications of hypogammaglobulinemia including recurrent infections, splenomegaly, and bronchiectasis prior to the formal assessment. It is possible some patients had pre-existing primary immune deficiency, but there was no screening lab prior to initiating rituximab. In addition, the time to diagnosis varied from months to years post-rituximab. Earlier diagnosis may have prevented many complications in our patient population.

CONCLUSIONS:

This highlights the need for a protocol for pre- and post-rituximab immunoglobulin evaluation to reveal any unmasked primary or developing secondary immunodeficiency prior to the onset of complications. This protocol could be effectively utilized by immunologists or other specialists caring for patients who need rituximab and would ensure prompt referral to immunology for appropriate treatment recommendations.