Sickle Cell Trait and Renal disease

Are there any association of sickle cell trait( SCT) and renal disease? Sickle cell disease and renal disease has been well established, but SCT and renal disease is an area understudied. A recent JAMA study showed association using a registry data.  Primary outcomes were CKD , incident CKD, albuminuria and decline in eGFR. The study concluded that among African Americans in these cohorts, the presence of SCT was associated with an increased risk of CKD, decline in eGFR, and albuminuria, compared with noncarriers.

What type of diseases do we see with SCT in the kidney? In SCT, injection radiographs demonstrate renal medullary vascular disruption, though to a lesser extent than seen in sickle cell disease, suggesting that sickle hemoglobin may have a dose-dependent relationship with kidney injury.  Our finding that SCT was related to both CKD and albuminuria is consistent with these proposed mechanisms. SCT is 4-5 times more common than sickle cell disease.  Hematuria by far is the most common complication of SCT especially seen in African Americans.  Admission rate in one study with patients with SCT and hematuria was 4%.  

The most common renal involvement in SCT are:

1.    Papillary necrosis ( most common)

2.    Renal infarction

3.    Isosthenuria

4.    Increased risk of exercise induced rhabdomyolysis

5.    Renal medullary carcinoma( very rare)

6.    Earlier onset of ESRD if also have ADPKD