Patient Guide

Kidney Health Tests — Complete Guide

Chronic kidney disease often has no symptoms until kidneys are significantly damaged. These blood and urine tests catch problems early — when treatment works best.

The complete kidney test panel

TestNormalWhat it checks
Serum Creatinine0.6–1.35 mg/dLKidney filtering efficiency
eGFR>90 mL/min% of kidney function remaining
Blood Urea Nitrogen (BUN)7–20 mg/dLProtein waste in blood
BUN:Creatinine Ratio10:1 – 20:1Dehydration vs kidney damage
Urine RoutineNo protein, no RBCKidney leakage
Urine Microalbumin<30 mg/g creatinineEarliest sign of kidney damage
Serum ElectrolytesNa 136–145, K 3.5–5.1 mEq/LFluid and salt balance
Uric Acid<7.2 mg/dL (men)Gout and kidney stones risk

Who should get regular kidney tests?

The most important early warning sign: urine microalbumin

Microalbuminuria — catch kidney damage years early

Normal kidneys do not let albumin (a large protein) escape into urine. The earliest sign of diabetic or hypertensive kidney damage is tiny amounts of albumin leaking through (microalbuminuria: 30–300 mg/g creatinine). This is detectable years before creatinine rises or eGFR drops. At the microalbuminuria stage, kidney damage is almost completely reversible with tight blood pressure and sugar control. Once creatinine rises significantly, damage is mostly irreversible — which is why early testing matters so much.

Questions to ask your doctor

Medical Disclaimer: This page is for general educational purposes only. It does not constitute medical advice. Always consult a qualified doctor before making any health decisions.