Urine and blood tests are used to detect and monitor kidney disease. Currently, the key markers used include abnormal urine albumin levels and a persistent reduction in the estimated glomerular filtration rate (eGFR). Identification of the etiology may help guide management. Diabetes and hypertension are the leading causes of CKD in adults. Many diseases that cause kidney failure may have their origins in childhood. Early detection and appropriate treatment may improve prognosis in all age groups.
Screen people at risk for CKD, including those with
The benefit of CKD screening in the general population is unclear.
The two key markers for CKD are urine albumin and eGFR. To screen for CKD:
CKD is generally diagnosed when there is evidence, for more than 3 months, of
Staging systems for chronic disease should identify risk for progression and complications. The current staging system for CKD, based exclusively on eGFR, does not appear to reliably identify those people at greatest risk for progression. Emerging research suggests an approach that includes multiple factors, such as urine albumin, age, and diabetes status may better predict progression.
In addition, the current staging requires accuracy of eGFR above 60 mL/min/1.73 m2. However, values above 60 calculated using the MDRD Study equation are not accurate. NKDEP encourages laboratories to report eGFR above 60 as "≥ 60" rather than as numerical values.
Although kidney function tends to decrease with age, this process has not been well investigated. Many people with age-related kidney function decline may not progress to kidney failure. Thus, the prognosis for a 75-year-old patient with an eGFR of 55 may be different than that for a 45-year-old patient with the same eGFR.
In addition, GFR may be too narrow a basis on which to assess risk for progression. The approach to staging is likely to evolve as it is informed by ongoing longitudinal research, e.g., the Chronic Renal Insufficiency Cohort Study.
Because kidney damage is generally irreversible, it is important to identify the etiology as early as possible. Specific treatments are available in many cases (e.g., membraneous nephropathy, lupus nephropathy) and a diagnosis will guide management.
Although diabetes is the most common cause of CKD, it is important not to assume that a patient with diabetes and CKD has diabetic kidney disease. However, non-diabetic kidney disease is unlikely in a person with diabetes of long duration with other diabetic complications, physical findings of end-organ diabetic damage, and negative screening laboratory studies.
If a patient with diabetes has retinopathy, albuminuria, and negative screening tests listed above, it is reasonable to assume the diagnosis is diabetic kidney disease. Patients who do not conform to these criteria should be discussed with a nephrologist.
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Page last updated: March 28, 2012