From the Guidelines
The initial workup of Chronic Kidney Disease (CKD) should include testing people at risk for and with CKD using both urine albumin measurement and assessment of glomerular filtration rate (GFR) as recommended by the KDIGO 2024 clinical practice guideline 1. The initial steps in the workup of CKD involve several key components to establish diagnosis, determine severity, identify underlying causes, and guide management.
- Obtain a comprehensive medical history focusing on risk factors such as diabetes, hypertension, family history of kidney disease, and medication use (especially NSAIDs and nephrotoxic drugs).
- Perform laboratory tests including serum creatinine to calculate estimated glomerular filtration rate (eGFR), which defines CKD when below 60 mL/min/1.73m² for more than 3 months.
- Conduct a urinalysis to assess for proteinuria, hematuria, and other abnormalities, along with a urine albumin-to-creatinine ratio (UACR) to quantify albuminuria.
- Complete blood count, comprehensive metabolic panel, lipid profile, and hemoglobin A1c (if diabetic) are essential baseline tests.
- Renal ultrasound should be performed to evaluate kidney size, structure, and rule out obstruction. These initial steps help stage CKD (based on eGFR and albuminuria), identify modifiable risk factors, and determine appropriate management strategies to slow disease progression and prevent complications, as emphasized by the KDIGO 2024 guideline 1. The importance of early detection and intervention in CKD is highlighted by the potential to reduce morbidity and mortality, and improve quality of life, which is a key consideration in the management of CKD 1.
From the Research
Initial CKD Workup
The initial steps in the workup of Chronic Kidney Disease (CKD) involve several key components, including:
- Screening for patients with risk factors, such as diabetes mellitus, hypertension, and a history of cardiovascular disease 2
- Measurement of serum creatinine, urine albumin/creatinine ratio, and urinalysis to detect persistently elevated serum creatinine and albuminuria, which are diagnostic and prognostic hallmarks of CKD 2
- Estimation of glomerular filtration rate (GFR) to diagnose and stage CKD, with a GFR <60 mL/min/1.73 m2 or albuminuria ≥30 mg per 24 hours indicating CKD 3
- Assessment of urine albumin/creatinine ratio and urine protein/creatinine ratio to identify patients with high levels of albuminuria or proteinuria, which are associated with adverse renal and cardiovascular outcomes 2
Diagnostic Tests
Diagnostic tests for CKD include:
- Serum creatinine measurement to estimate GFR 2
- Urine albumin/creatinine ratio or urine protein/creatinine ratio to detect albuminuria or proteinuria 2
- Urinalysis to detect hematuria, proteinuria, or other abnormalities 2
- Serum cystatin C measurement, which is a novel biomarker that can be useful in certain situations, such as when a false-positive decreased estimated GFR is suspected 2
Referral to Nephrologist
Referral to a nephrologist is indicated for patients with:
- An estimated GFR less than 30 mL per minute per 1.73 m2 2
- Persistent urine albumin/creatinine ratio greater than 300 mg per g or urine protein/creatinine ratio greater than 500 mg per g 2
- Evidence of a rapid loss of kidney function 2
- Other complications of CKD, such as hyperkalemia, metabolic acidosis, hyperphosphatemia, vitamin D deficiency, secondary hyperparathyroidism, or anemia 3
Management
Management of CKD involves a multidisciplinary approach, including:
- Cardiovascular risk reduction, such as statins and blood pressure management 3
- Treatment of albuminuria, such as angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers 3
- Avoidance of potential nephrotoxins, such as nonsteroidal anti-inflammatory drugs 3
- Adjustments to drug dosing, such as many antibiotics and oral hypoglycemic agents 3
- Lifestyle modifications, such as dietary changes, physical activity, and smoking cessation 4, 5