Diabetic nephropathy--the family physician's role.

Nearly one-half of persons with chronic kidney disease have diabetes mellitus. Diabetes accounted for 44 percent of new cases of kidney failure in 2008. Diabetic nephropathy, also called diabetic kidney disease, is associated with significant macrovascular risk, and is the leading cause of kidney failure in the United States. Diabetic nephropathy usually manifests after 10 years' duration of type 1 diabetes, but may be present at diagnosis of type 2 diabetes. Screening for microalbuminuria should be initiated five years after diagnosis of type 1 diabetes and at diagnosis of type 2 diabetes. Screening for microalbuminuria with a spot urine albumin/creatinine ratio identifies the early stages of nephropathy. Positive results on two of three tests (30 to 300 mg of albumin per g of creatinine) in a six-month period meet the diagnostic criteria for diabetic nephropathy. Because diabetic nephropathy may also manifest as a decreased glomerular filtration rate or an increased serum creatinine level, these tests should be included in annual monitoring. Preventive measures include using an angiotensin- converting enzyme inhibitor or angiotensin II receptor blocker in normotensive persons. Optimizing glycemic control and using an angiotensin-converting enzyme inhibitor or angiotensin II receptor blocker to control blood pressure slow the progression of diabetic nephropathy, but implementing intensive glycemic and blood pressure control is associated with more adverse outcomes. Low-protein diets may also decrease adverse renal outcomes and mortality in persons with diabetic nephropathy.