Diabetic nephropathy: pathophysiology, clinical course and susceptibility.

Abstract

The clinical diagnosis of diabetic nephropathy in an insulin-dependent patient relies on the detection of persistent proteinuria (i.e., urinary total protein excretion rate greater than 0.5 g/24h) after 10 years or more of the disease, with concomitant diabetic retinopathy and rising arterial pressure, but without signs of other renal disease, urinary tract infection or heart failure. Diabetic glomerulosclerosis is found at renal biopsy in over 90% of the cases, confirming the diagnosis (1,2). Epidemiological studies show that, cumulatively, nephropathy develops in approximately 35% of insulin-dependent patients, and it is mostly in this kind of patient that the natural history of this disorder has been outlined (1,3). Noninsulin-dependent diabetics of European origin seem to develop nephropathy less frequently than insulin-dependent patients, but because of their larger number, the actual number of patients developing end-stage renal failure is approximately the same (4).