Renal dysfunction in patients with sickle cell anemia or sickle cell trait

Abstract

Patients with sickle cell anemia (Hb SS) or sickle cell trait (Hb AS) may present several types of renal dysfunction; however, comparison of the prevalence of these abnormalities between these two groups and correlation with the duration of disease in a large number of patients have not been thoroughly investigated. In a cross-sectional study using immunoenzymometric assays to measure tubular proteinuria, microalbuminuria, measurement of creatinine clearance, urinary osmolality and analysis of urine sediment, we evaluated glomerular and tubular renal function in 106 adults and children with Hb SS (N = 66) or Hb AS (N = 40) with no renal failure (glomerular filtration rate (GFR) >85 ml/min). The percentage of individuals with microalbuminuria was higher among Hb SS than among Hb AS patients (30 vs 8%, P<0.0001). The prevalence of microhematuria was similar in both groups (26 vs 30%, respectively). Increased urinary levels of retinol-binding protein or ß 2 -microglobulin were detected in only 3 Hb SS and 2 Hb AS patients. Urinary osmolality was reduced in patients with Hb SS or with Hb AS; however, it was particularly evident in Hb SS patients older than 15 years (median = 393 mOsm/kg, range = 366-469) compared with Hb AS patients (median = 541 mOsm/kg, range = 406-722). Thus, in addition to the frequently reported early reduction of urinary osmolality and increased GFR, nondysmorphic hematuria was found in 26 and 30% of patients with Hb SS or Hb AS, respectively. Microalbuminuria is an important marker of glomerular injury in patients with Hb SS and may also be demonstrated in some Hb AS individuals. Significant proximal tubular dysfunction is not a common feature in Hb SS and Hb AS population at this stage of the disease (i.e., GFR >85 ml/min).

High Prevalence of Sickle Cell Trait in African Americans with ESRD

“…3,6,7,10,11 The rare renal medullary carcinoma is seen almost exclusively among HbAS patients. 6,11,12 In epidemiologic studies, the presence of HbAS has been associated with microalbuminuria and proteinuria, particularly among diabetic men, 13,14 and African Americans with autosomal dominant polycystic kidney disease (AD-PKD) and HbAS have been shown to progress to ESRD more rapidly than those without the trait. 15 With its associated structural and physiologic changes, HbAS could adversely affect renal function, especially in the setting of comorbid disease, and may represent a potential risk factor for kidney disease.…”

Nocturnal Enuresis in Children and Adolescent with Sickle cell Anemia

“…The first study that linked hyposthenuria and nocturnal enuresis was in 1967 by Noll et al [43]. This assumption was based on the fact that failure to concentrate urine is one of the earliest infarction-related renal complication of SCA [44].…”

“…Enuresis and nocturia, as indicators of UBD, are common in individuals with sickle cell anemia [18,43,53,54]. Field et al reported that enuresis declined with age but nocturia persisted throughout childhood and early adulthood [18].…”

Murine glutathione S‐transferase A1‐1 in sickle transgenic mice

“…The pathophysiology of renal damage and proteinuria in this population is unclear [9]. The proposed process involves ischemia and microinfarction resulting from medullary hypoxia, acidosis, and hyperosmolarity, an environment that promotes red blood cell (RBC) sickling.…”