Health literacy and knowledge of chronic transfusion therapy in adolescents with sickle cell disease and caregivers.

BACKGROUND: Patients with sickle cell disease (SCD) may require chronic transfusion therapy (CTT) for prevention of stroke or other complications. Limited health literacy (HL) is common and is associated with poor health-related knowledge and outcomes in chronic disease. We sought to assess HL and transfusion knowledge in patients with SCD on CTT and their caregivers. METHODS: A cross-sectional study of patients was conducted in outpatient hematology clinics. Forty-five pairs of adolescent patients and caregivers and 20 caregivers of pre-adolescent patients completed the Newest Vital Sign HL assessment and answered questions assessing SCD and transfusion knowledge. Community-level median income and unemployment rates were estimated from Census data. We computed the correlation of HL with knowledge and compared each to Census variables, payor status, educational attainment, and stroke. RESULTS: HL was inadequate in 22 (34%) caregivers and 31 (69%) adolescents. Adequate caregiver HL was associated with higher educational attainment but not community-level socioeconomics or payor status. Mean knowledge score was lower in adolescents than in caregivers and correlated with age in adolescents (r = 0.42, P = .004). HL correlated with knowledge (r = 0.46, P < .0001). There were no significant correlations of HL or knowledge between adolescents and their caregivers. Neither HL nor knowledge was associated with prior stroke. The greatest knowledge was demonstrated for iron overload and SCD genotype, whereas knowledge gaps existed in alloimmunization, indication for CTT, and SCD curative therapy. CONCLUSIONS: Enhanced educational resources in transfusion therapy, alloimmunization, and curative therapy are needed for patients with SCD and caregivers of all HL levels.

Class I and II HLA antibodies in pediatric patients with thalassemia major.

BACKGROUND: HLA alloimmunization is a potential complication of red blood cell (RBC) transfusion with detrimental consequences for future organ or hematopoietic stem cell transplantation. STUDY DESIGN AND METHODS: The study aimed to determine the prevalence and specificity of HLA antibodies among pediatric patients with thalassemia major (TM) and antibody changes over time while on leukoreduced chronic transfusion therapy. HLA antibodies were measured at two or more time points in children and young adults ages 3 to 21 years with TM. HLA Class I and II antibodies were measured by FlowPRA screening. Positive screening assays were confirmed with LabScreen single-antigen bead assays for antibody specificity. RESULTS: HLA antibodies were detected in 10 of 19 (53%) subjects: seven of 19 (37%) with HLA Class I and II antibodies, two of 19 (11%) with only HLA Class I antibodies, and one of 19 (5%) with only HLA Class II antibodies. Subjects with HLA antibodies were older (14.6 years vs. 7.1 years, p = 0.05), predominantly male (80%), and more likely to have a remote history of nonleukoreduced transfusions (p = 0.057). Median time between testing was 3.7 years. De novo HLA antibodies were detected in two of 11 patients who initially had negative panel-reactive antibody screens, while one subject lost detection of Class II antibody. Two of seven patients with HLA antibodies had antibodies to self-HLA. CONCLUSION: HLA antibodies have a high prevalence in TM patients and may be associated with nonleukoreduced transfusions and older age. For such patients, antibody identification will be useful if subsequent organ or stem cell transplantation is needed.