Do I have kidney disease?

Determining if You Have Kidney Disease

To know if you have kidney disease, you need two specific tests: a blood test to estimate your kidney function (eGFR from serum creatinine) and a urine test to check for kidney damage (urine albumin-to-creatinine ratio). Without these laboratory values, kidney disease cannot be ruled in or out, as chronic kidney disease is typically asymptomatic in its early stages 1, 2.

What Defines Kidney Disease

Chronic kidney disease (CKD) is defined as either:

• Decreased kidney function: eGFR less than 60 mL/min/1.73 m² for at least 3 months 1
• Kidney damage markers: Primarily persistent proteinuria (albumin-to-creatinine ratio >30 mg/g) for at least 3 months, regardless of eGFR level 1

The 3-month duration is critical - a single abnormal test does not confirm CKD; the abnormality must persist for more than 3 months to distinguish chronic kidney disease from acute kidney injury 1.

Required Testing to Answer Your Question

Blood Test for Kidney Function

• Serum creatinine should be measured and used with a GFR estimating equation (not creatinine alone) to calculate eGFR 1
• Normal eGFR in young adults is approximately 120-130 mL/min/1.73 m², declining with age 1
• eGFR <60 mL/min/1.73 m² represents loss of half or more of normal kidney function and defines CKD stages G3-G5 1

Urine Test for Kidney Damage

• Spot urine albumin-to-creatinine ratio (UACR) is the preferred test 1, 3
• Normal: <30 mg/g creatinine 1
• Moderately elevated albuminuria: 30-300 mg/g creatinine 1
• Severely elevated albuminuria: ≥300 mg/g creatinine 1
• Avoid dipstick-only testing as it is susceptible to false results due to urine concentration variations 1

Why You Cannot Self-Diagnose

CKD is usually asymptomatic until advanced stages, making it impossible to determine kidney disease status based on symptoms alone 1, 2. Many people with CKD are diagnosed only after chance findings from screening tests 2. Even when symptoms occur (lethargy, itch, loss of appetite), they are non-specific and appear late in disease progression 2.

Risk Factors That Warrant Testing

You should be tested if you have:

• Diabetes - the leading cause of CKD, affecting 20-40% of people with diabetes 1, 2
• Hypertension - a major cause of CKD 1, 2
• Older age - CKD prevalence increases significantly with age; approximately 17% of persons over 60 have eGFR <60 mL/min/1.73 m² 1
• Ethnic minority status in the US (African American, American Indian, Hispanic, Asian or Pacific Islander) 1
• Family history of kidney disease 1

Critical Pitfall to Avoid

Do not rely on serum creatinine level alone - it must be converted to eGFR using validated equations that account for age, sex, race, and body size 1. A "normal" creatinine can mask significantly reduced kidney function, especially in elderly or smaller individuals 1.

Next Steps

If you have not had these tests performed:

• Request serum creatinine with eGFR calculation from your physician 1
• Request spot urine albumin-to-creatinine ratio 1, 3
• If either test is abnormal, repeat testing after 3 months to confirm chronicity 1

If you have continuously increasing urinary albumin, decreasing eGFR, or eGFR <30 mL/min/1.73 m², you should be referred to a nephrologist 1, 3.