Disparity in HLA Typing Rates Among Hospitalized Pediatric Patients with Sickle Cell Disease

Abstract

Hematopoietic stem cell transplantation (HSCT) using an HLA-identical sibling donor is a well-established cure for sickle cell disease (SCD). The proportion of patients with SCD who have completed HLA typing, a key first step in considering HSCT, is unknown. We sought to determine the prevalence of HLA typing among patients with SCD hospitalized at our institution, identify characteristics associated with having had typing, and describe the acceptability of this testing. Area deprivation index (ADI) was studied as a measure of family socioeconomic status. Among 291 hospitalized patients with SCD, 71 (24%) had HLA typing at study baseline. On multivariate analysis, HLA typing at baseline was associated with hydroxyurea (OR 3.10, p=0.003) and chronic transfusion therapy (OR 7.04, p<0.001), prior intensive care unit admission (OR: 1.89, p=0.04), and ADI score (OR 0.74, p=0.004). Patients who lived in more disadvantaged neighborhoods were less likely to have had HLA typing. Among patients with healthy full siblings, 69% of families without typing at baseline were interested in obtaining testing when explictly offered. These findings suggest that continued work is needed to raise family awareness of HLA typing and ensure equal access to curative therapy for SCD.