central to renal injury, decreasing this by haptoglobin infusions is a novel approach. Clinical studies in nonsickle cell patients suggest this may be beneficial.55,56 Sickle cell patients often have a delay in initiation of early therapy for advanced renal disease, which results in increased mortality. Improved multidisciplinary care with planning of vascular access, transfusion therapy, initiation of dialysis, and listing on a renal transplantation registry are major priorities and improve survival.38,57 Recent studies indicate a trend toward improved survival for kidney transplantation. Although survival at 6 years is lower for SCD compared with nonSCD, it has increased to 70%. When matched for multiple covariates, SCD survival is comparable to African Americans with diabetes as a cause of renal failure.58 Adjustment of narcotic analgesia dosing based on renal clearance needs to be considered. Sickle cell patients with renal failure usually have erythropoietin resistance. Chronic transfusion therapy is often necessary. Hydroxyurea with erythropoietin is often initially used. Hemosiderosis is a serious problem in renal failure; iron chelators should be routinely used in patients on dialysis who have hemosiderosis.57 Morbidity and mortality from comorbid complications including thrombosis, cardiac failure, stroke, and infection are more frequent in chronic renal failure patients and can be minimized with patient education and early intervention.59 In summary, chronic organ dysfunction is a major cause of sickle cell morbidity and death in adult patients. More aggressive monitoring and improved treatments are necessary. The etiology of organ failure in the adult population overlaps with many of the risk factors seen in pediatrics. Pediatric and adult patients share some common phenotypes and biomarkers,60,61 such as stroke and renal disease. There may be differences in the biology- and age-dependent potential therapy. In adults, clinical problems such as pulmonary hypertension, cardiac dysfunction, and cardioembolism may be more important than in pediatrics. Biomarkers of intima-media thickness, nitric oxide dysfunction, natriuretic peptide, and genetic variance of free hemoglobin processing such as ApoL1 and HMOX1 may play a more important role in the older population.62,63 More research in chronic organ failure in adults is critical. Longitudinal studies correlating age, phenotype, genotype, biologic markers, and response to therapy are essential to better understand age-specific therapy. Correspondence Elliott Vichinsky, UCSF Benioff Children’s Hospital Oakland, 747 52nd St, Oakland, CA 94609. e-mail: evichinsky@mail.cho.org. References 1. Thein MS, Igbineweka NE, Thein SL. Sickle cell disease in the older adult. Pathology. 2017;49(1):1-9. 2. Gardner K, Douiri A, Drasar E, et al. Survival in adults with sickle cell disease in a high-income setting. Blood. 2016;128(10):1436-1438. 3. 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