All reported affected individuals have eventually developed renal dysfunction. The kidney disease is characterized by progressively worsening loss of protein in the urine and ultimately concludes with renal failure. The progressive renal disease is not responsive to immunosuppressant therapy. The diagnosis of renal dysfunction is usually made concurrent with or within the five years following the diagnosis of the growth failure. Renal failure requiring dialysis or kidney transplantation usually develops within the subsequent 11 years, although the rate of progression varies greatly. Because renal disease causes high blood pressure and high levels of blood cholesterol and lipids, the theory is that it accentuates the vascular disease of SIOD; however, renal transplantation does not prevent progression of the atherosclerosis. The incidence of a single kidney may be higher than in the unaffected population and this is associated with a more rapid onset of renal failure.
-National Organization for Rare Disorders