Applying clinical guidelines –
✓ Determine patient risk.
- All patients should be assessed for chronic kidney disease (CKD) risk factors as part of their routine physical examination.
- Major risk factors for CKD and end-stage renal disease (ESRD) include diabetes, hypertension, cardiovascular disease, and family history of kidney disease.
- Being African American, Hispanic, or Native American increases the risk.
Other clinical risk factors include:
- Acute kidney injury (AKI)
- Metabolic syndrome
- Autoimmune disease
- Systemic infection
- Lower urinary tract obstruction
- Drug toxicity
✓ Test at-risk patients.
Two simple tests will detect kidney disease:
1. Spot urine albumin to creatinine ratio to determine albuminuria (UACR).
Albuminuria is present when UACR is > 30 mg/g and indicates possible kidney damage.
2. Serum creatinine applied to a prediction equation to estimate glomerular filtration rate (eGFR). eGFR is more accurate than serum creatinine alone. Serum creatinine is affected by muscle mass, age, sex, and race.
The National Kidney Disease Education Program recommends using the isotope dilution mass spectrometry (IDMS)-traceable Modification of Diet in Renal Disease (MDRD) Study equation to estimate GFR from serum creatinine in adults.
GFR (ml/min/1.73m2) = 175 x (Scr)-1.154 x (Age)-0.203 x (0.742 if female) x (1.212 if African American) [conventional units]
This equation does not require weight because the results are reported normalized to 1.73m2 body surface area, which is an accepted average adult surface area.
Kidney disease may be present when the calculated GFR value is < 60 ml/min/1.73m2.
✓ To confirm the presence of CKD, clinical marker(s) of kidney damage and/or decreased kidney function must be present ≥ 3 months.
- Albuminuria: > 30 mg of urinary albumin per gram of urinary creatinine (UACR) and/or
- eGFR: < 60 ml per minute per 1.73m2.
- If UACR is > 30 mg/g at initial testing, repeat UACR within 3 months.
- A minimum of 2 out of 3 elevated UACRs present for ≥ 3 months indicates kidney damage and an initial diagnosis of CKD.
- If eGFR is < 60 ml/min/1.73m2 at initial testing, repeat eGFR test within 14 days.
- If eGFR is stable or reduced, repeat eGFR test again within 3 months.
- A minimum of 3 reduced eGFRs present for ≥ 3 months indicates reduced kidney function and an initial diagnosis of CKD.