Prevalence and progression of chronic kidney disease in adult patients with sickle cell disease.

AIM: We evaluated the prevalence and progression of chronic kidney disease (CKD) during the 5-year period in a cohort of patients with sickle cell disease (SCD) aged 18 years and older. METHODS: We studied 98 patients with SCD. Chronic kidney disease stages I through V were defined based on estimated glomerular filtration rate (eGFR), and albuminuria grades were defined based on spot urine protein-to-creatinine ratio according to the 2012 Kidney Disease Improving Global Outcomes recommendations. In patients with eGFR of greater than 60 mL/min per 1.73 m(2), CKD was diagnosed if grade A2 or A3 albuminuria was present. Chronic kidney disease progression was defined as an increase in CKD stage with an additional eGFR reduction of more than 25% from baseline. RESULTS: At baseline, 28.6% of patients had CKD. After a mean follow-up of 5.0 (SD, 0.9) years, 17 patients developed new CKD and the overall CKD prevalence increased to 41.8%. In addition, 8 patients experienced CKD progression. The following baseline variables were associated with the development and progression of CKD in univariate analysis: older age (P = 0.003), higher systolic blood pressure (BP; P = 0.003), lower eGFR (P = 0.001), higher serum creatinine (P = 0.001), and A3 albuminuria (P = 0.008). In multivariate analysis, baseline A3 albuminuria (adjusted odds ratio, 5.0; 95% confidence interval, 1.1-24.3; P = 0.048) and each 1-mm Hg increase in systolic BP (adjusted odds ratio, 1.04; 95% confidence interval, 1.0-1.07; P = 0.039) predicted CKD development and progression. CONCLUSIONS: Chronic kidney disease is common in patients with SCD and its prevalence increases with age. Several baseline modifiable and nonmodifiable factors were associated with the development and progression of CKD in patients with SCD. Strategies targeting BP control and proteinuria may be beneficial for individuals with SCD.

Leg ulcers in sickle cell disease: current patterns and practices.

Leg ulcers are a debilitating complication of patients with sickle cell disease, and their frequency in North America was reported to be 2.5% by the Cooperative Study of Sickle Cell Disease more than 20 years ago. We sought to determine if the frequency of leg ulcers in sickle cell patients in the United States had declined and to assess which treatments providers use most commonly. We sent an e-mail survey to health professionals belonging to the national Sickle Cell Adult Provider Network. Responses were obtained from 31 of them (26.0%). Most of them (96.0%) reported having some patients with leg ulcers. Providers reported a total of 185 patients with active leg ulcers and 224 in the previous 5 years, for a total of 409 patients. Hb SS (homozygous sickle cell anemia) was the most common genotype of affected individuals, followed by Hb SC (double heterozygote for Hb S [ß6(A3)Glu→Val, GAG>GTG; HBB: c.20A>T] and Hb C [ß6(A3)Glu→Lys, GAG>AAG; HBB: c.19G>A]). Males showed a 2:1 predominance. Two-thirds of patients were treated with either hydroxyurea (HU) or transfusion therapy and most used compression stockings and topical therapies as directed by wound care services. We conclude that leg ulcers continue to be a debilitating complication of young adults with sickle cell disease, despite improved supportive care and the widespread use of disease modifying agents such HU and transfusion. While some providers offer office-based ulcer care, the majority prefer specialty consultation including podiatry, plastic surgery and dermatology. Despite their frequency, there is no clear consensus among providers as to the best treatment.

Phenocopy of warfarin syndrome in an infant born to a mother with sickle cell anemia and severe transfusional iron overload.

Neonatal chondrodysplasia punctata (CDP) is characterized by epiphyseal stippling and midfacial hypoplasia. CDP is usually inherited, but can be acquired because of maternal vitamin K deficiency. We describe an infant with CDP born to a teenager with sickle cell anemia and transfusional iron overload. The mother had severe liver fibrosis, elevated liver iron concentration (34 mg Fe/g), and coagulopathy, but no gestational use of warfarin. Fetal abnormalities were attributed to vitamin K deficiency secondary to liver dysfunction from iron toxicity. Treatment of iron overload among women with sickle cell anemia of childbearing potential is important to avoid possible CDP in newborns.