#55
IVIG THERAPY FOR PLATELET REFRACTORINESS DUE TO HLA CLASS I ANTIBODIES: A CASE REPORT.
Tal Z. Zaks, MD, PhD and Deborah Sesok-Pizzini MD . Philadelphia PA, University of Pennsylvania School of Medicine, 19104, Hematology Oncology and Philadelphia PA, University of Pennsylvania School of Medicine, 19104, Blood Bank/Transfusion Medicine .
US-licensed intravenous immunoglobulin (IVIG) products are labeled for use as replacement therapy in patients with primary immunodeficiency. IVIG is also effective for idiopathic thrombocytopenic purpura, and has been used with variable success for alloimmune thrombocytopenia. We report a case study using IVIG as a therapy for platelet refractoriness due to HLA Class I antibodies.
Methods: a 59 year old African American woman suffering from MDS for 6 months was admitted with progressive thrombocytopenia requiring platelet transfusions. RAEB II was diagnosed and MEC induction chemotherapy was administered. She soon failed to respond to single donor platelets with an increase in post transfusion platelet counts. Her PRA showed 95% reactivity. Several subsequent transfusions of C and D HLA-matched platelets failed to yield a post count increment. IVIG therapy, 1 gm/kg, was given for 2 days and the patient continued to receive HLA-matched platelets.
Results: Additional D, C and B1X HLA-matched platelet transfusions became effective (see Figure) following the first day of IVIG therapy. Post transfusion counts improved and her petechiae, melena, and hematuria resolved.
Conclusion: The use of IVIG for alloimmune platelet refractoriness has been controversial. This case report suggests that in severe cases of platelet refractoriness due to HLA sensitization, IVIG may be of benefit when combined with HLA-matched platelet transfusions. Larger, randomized trials are needed to determine the effectiveness of this therapy.