CKD Screening: Recommended Tests and Intervals
Screen all patients with diabetes, hypertension, age >60 years, family history of kidney disease, cardiovascular disease, or obesity using both estimated glomerular filtration rate (eGFR) and urinary albumin-to-creatinine ratio (UACR) on a random spot urine sample. 1, 2
Who Should Be Screened
High-Risk Populations Requiring Immediate Screening
Diabetes mellitus patients should be screened immediately at diagnosis for type 2 diabetes (as CKD may already be present) and annually thereafter, as 20-40% will develop CKD within 10-15 years 1, 3
Hypertension patients require screening during chronic disease management, as 91% of CKD patients have hypertension and the combination dramatically accelerates kidney damage 1, 2
Age >60 years is a mandatory screening criterion, as CKD prevalence increases substantially with advancing age 1, 2
Family history of chronic kidney disease significantly increases risk, with affected individuals showing higher prevalence of hypertension, diabetes, and earlier CKD stages 1, 2
Cardiovascular disease patients should be screened, as 46% of CKD patients have atherosclerotic heart disease 1
Obesity is an established risk factor warranting screening 1, 2
Populations NOT Requiring Routine Screening
- Asymptomatic adults without risk factors should not be screened, as the USPSTF found insufficient evidence for universal screening and the risk of false positives and medication harms outweigh benefits in this low-risk population 4, 1
What Tests to Order
Essential Screening Tests (Both Required)
Estimated GFR (eGFR) calculated from serum creatinine using validated equations (CKD-EPI 2021), as serum creatinine alone is inadequate 1, 3
Urinary albumin-to-creatinine ratio (UACR) on a random spot urine sample, as eGFR and UACR provide independent prognostic information for cardiovascular events, CKD progression, and mortality 1, 5
Preferred Initial Laboratory Panel
Comprehensive metabolic panel (CMP) is preferred over a basic renal panel for high-risk patients, as it includes kidney function markers (creatinine, BUN, eGFR), electrolytes (sodium, potassium, chloride, bicarbonate), plus liver function tests and glucose 6
UACR must be ordered separately from the CMP, as it is mandatory for CKD diagnosis and risk stratification but not included in standard panels 6
Diagnostic Thresholds
CKD is diagnosed when eGFR <60 mL/min/1.73 m² OR UACR ≥30 mg/g persists for at least 3 months 1, 5
Albuminuria categories: Normal ≤30 mg/g, moderately increased (microalbuminuria) 31-300 mg/g, severely increased (macroalbuminuria) >300 mg/g 7
Confirmation requires 2 out of 3 urine specimens showing UACR >30 mg/g within a 3-6 month period 7
Screening Intervals
Initial Screening Frequency
- Annual screening for all high-risk patients (diabetes, hypertension, age >60, family history, cardiovascular disease, obesity) using both eGFR and UACR 1, 2
Risk-Stratified Monitoring After CKD Diagnosis
Low risk (eGFR 60-89 with UACR <30 mg/g): Annual monitoring of eGFR and UACR 1
Moderate risk (eGFR 45-59 or UACR 30-300 mg/g): Every 6 months (2 times per year) 1, 6
High risk (eGFR 30-44 or UACR >300 mg/g): Every 3-4 months (3-4 times per year) 1, 6
Very high risk (eGFR <30 mL/min/1.73 m²): Every 3 months with nephrology referral 6
Critical Timing Considerations
When to Defer Testing
- Active urinary tract infection: Defer albuminuria testing until infection is completely resolved and wait at least 2-4 weeks after treatment completion, as active UTI causes false-positive albuminuria results 7
Special Populations
Type 1 diabetes: Screening can begin 5 years after diagnosis or at puberty, as albuminuria rarely occurs earlier; if detected sooner, consider alternative causes and nephrology referral 7
Type 2 diabetes: Screen immediately at diagnosis, as 6.5% already have urinary albumin >50 mg/L and 28% have hypertension at diagnosis 1
Common Pitfalls to Avoid
Never rely on serum creatinine alone without calculating eGFR using validated equations, as this misses early CKD 1
Never skip albuminuria testing even if eGFR is normal, as both provide independent prognostic information 1
Never use dipstick urinalysis alone for albuminuria screening; always confirm with quantitative UACR in an accredited laboratory due to false results from urine concentration variations 7
Never interpret albuminuria results obtained during or immediately after UTI, as this is the most common error leading to false-positive CKD diagnoses and unnecessary interventions 7