Chronic Kidney Disease and Albuminuria in Children with Sickle Cell Disease

Abstract

Summary Background and objectives Sickle cell nephropathy begins in childhood and may progress to renal failure. Albuminuria is a sensitive marker of glomerular damage that may indicate early chronic kidney disease (CKD). Design, setting, participants, & measurements The aims of this study were to determine the cross-sectional prevalence and clinical correlates of albuminuria and CKD among children with sickle cell disease (SCD). Over a 10-year period (1995 to 2005) 410 pediatric SCD patients ages 2 to 21 years were enrolled: 261 with hemoglobin SS (HbSS) or HbSβ0 thalassemia (HbSβ0) and 149 with HbSC or HbSβ+ thalassemia (HbSβ+). The albumin/creatinine ratio (ACR) of spot-urine specimens and serum creatinine were measured; abnormal albuminuria was defined as urinary ACR ≥ 30 mg/g. Results The prevalence of abnormal albuminuria was 20.7% (23.0% in HbSS/HbSβ0, 16.8% in HbSC/HbSβ+). Among HbSS/HbSβ0, abnormal albuminuria was associated with increasing age and lower baseline hemoglobin. GFR, estimated in 189 patients using the updated Schwartz formula, correlated negatively with age (r = −0.27, P = 0.0002). CKD defined according to the Kidney Disease: Improving Global Outcomes study was present in 26.5% (50 of 189) of patients: stage 1 in 27 (14.8%) and stage 2 in 22 (11.6%). In multivariate analysis, age and HbSC/HbSβ+ genotype were associated with CKD. Conclusions This is the first study to stage CKD in children with SCD and highlights a high prevalence of albuminuria and glomerular injury early in life. Detecting CKD in childhood could allow for earlier intervention and prevention of renal failure in adulthood.

How I treat renal complications in sickle cell disease

“…16 In our own cohort of adult patients, microalbuminuria was detectable in 28% of patients in the 16-to 25-year age group, 38% in patients 26 to 35 years, 50% in those 36 to 45 years, and .60% in those 46 years of age or older. 6 In a subset of patients, microalbuminuria progresses to unselective proteinuria, occasionally becoming nephrotic in range (.3 g total protein in 24 hr) after many years.…”

Renal Tubular Dysfunction in Sickle Cell Disease

“…Urine endothelin-1 was also found to be associated with microalbuminuria in SCD patients, as well as with urinary concentration defect [26]. Albuminuria has been described in 16 to 60% of adults with SDC [5,18,20,21,22,27], and has significant correlation with age [11,19,24]. No patient in our cohort developed nephrotic range proteinuria, which is really rare in SCD [5].…”

Acute kidney injury in children with sickle cell disease—compounding a chronic problem

“…However, data on the prevalence of CKD in childhood SCD are relatively scarce. McPherson Yee reported a CKD (eGFR <90 ml/min/1.73m 2 ) prevalence of 12% of their cohort of 410 children with SCD [22], using serum creatinine and a modified Schwartz formula to calculate eGFR [23]. Similarly, Bodas et al recently reported a CKD prevalence of 8% in a cohort of patients with SCD aged 3-17 years, using the same CKD criteria and the same eGFR calculation [24].…”