Hyperfiltration is associated with the development of microalbuminuria in patients with sickle cell anemia

Renal Complications of Sickle Cell Syndrome in Southern Iran

“…During adolescence both GFR and RPF are normal, but are frequently subnormal after the age of 40. Progressive renal insufficiency in these patients has been ascribed to hyperfiltration-mediated sclerosis of the glomerular capillaries (13). In a more recent study, Schmitt et al, found enhanced macromolecule trafficking, decreased glomerular size selectivity, and at later stages, the reversible changes are no longer detected, and even a decrease in Kf may contribute to the decrease in GFR (14).…”

The spectrum of sickle hemoglobin-related nephropathy: from sickle cell disease to sickle trait

“…In the BABY HUG study, elevated glomerular filtration rate (GFR) ≥ 110 mL/min/1.73 m 2 as measured directly by plasma clearance of 99m Tc-DTPA was present in over 50% of infants from 9 months to 1 year and demonstrated progressive escalation with increasing age beyond 15–19 months [28]. This increase in GFR appears to continue to progress well into young adulthood with nearly all children >2.5 years of age demonstrating elevated GFR in the HUSTLE study [29], and nearly all adults age 18–30 years also demonstrating high creatinine-based eGFR ≥ 130 mL/min/1.73 m 2 [30]. As the degree of renal clearance declines, however, eGFR levels also appear to drop off, starting around age 30–40 [30].…”

“…This increase in GFR appears to continue to progress well into young adulthood with nearly all children >2.5 years of age demonstrating elevated GFR in the HUSTLE study [29], and nearly all adults age 18–30 years also demonstrating high creatinine-based eGFR ≥ 130 mL/min/1.73 m 2 [30]. As the degree of renal clearance declines, however, eGFR levels also appear to drop off, starting around age 30–40 [30]. Whether similar glomerular hyperfiltration occurs in SCT is unknown, although one small study of Congolese children suggested that hyperfiltration defined as creatinine-based eGFR >140 mL/min/1.73 m 2 was more common in SCT than hemoglobin AA controls [31].…”

“…Baseline hyperfiltration of eGFR >130–140 mL/min/1.73 m 2 is associated with the development of microalbuminuria (urine albumin 30–299 mg/g creatinine) in adults with SCA [30]. Albuminuria >30mg/g has also been found in over 20% of SCD children, with greater than 60% of patients with SCA demonstrating albuminuria by adulthood [35,36].…”

Genetic variants and cell-free hemoglobin processing in sickle cell nephropathy

“…36,37 Urine concentrations of hemoglobin (Bethyl laboratories, Montgomery, TX, USA) and kidney injury molecule-1 (KIM-1) (R&D Systems, Minneapolis, MN, USA) were measured using enzyme-linked immunosorbent assays (ELISA). Urine albumin and creatinine values were determined by the UIC Clinical Pathology Laboratories using methods approved by Clinical Laboratory Improvement Amendments.…”