Understanding Your Labs
What your blood and urine tests measure, what to track, and the question to ask at every visit.
Why labs matter in CKD
Your labs are how your care team tracks kidney function, catches problems early, and adjusts treatment. The numbers on the printout aren’t a verdict — they’re a conversation starter. The more you understand what each one means, the more useful those conversations become.
How often labs are drawn changes with your stage. Early stages might be every 6–12 months. Stage 3 is typically every 3–6 months. Stage 4 moves to every 1–3 months, and Stage 5 is monthly or more often if you’re on dialysis.
Kidney function
Most relevant:All stagesEstimates how many milliliters of blood your kidneys filter each minute. A healthy young adult is around 100–120 mL/min.
eGFR comes from your creatinine blood test, your age, and your sex, run through the CKD-EPI 2021 equation. The 2021 update removed the race coefficient — so older results may look a bit different from newer ones for Black patients.
What to track: the trend over three months or more, not a single reading. The question to ask is “Is my GFR stable, rising, or falling?”
Things that can move eGFR by 5–10 points without anything changing in your kidneys: hydration, a big protein meal the day before, intense exercise, certain medications. ACE inhibitors and ARBs often cause a small expected dip when started— that’s usually a sign they’re doing their protective job, not a sign of harm.
Cross-reference: Understanding your GFR and the CKD Stages section.
Urine tests
Most relevant:All stagesMeasures protein (specifically albumin) leaking into urine. Healthy kidneys keep albumin in your blood, not your urine.
- Normal: less than 30 mg/g
- Moderately increased(formerly “microalbuminuria”): 30–300 mg/g
- Severely increased: over 300 mg/g
UACR is an independent risk factor for both kidney progression and cardiovascular disease — and it’s a treatment target your team actively works on (ACE/ARB and SGLT2 inhibitors reduce it). Can be done from a single urine sample; no 24-hour collection needed.
Electrolytes & minerals
Most relevant:More relevant Stages 3–5Blood count & anemia
Most relevant:More relevant Stages 3b–5Bone & mineral metabolism
Most relevant:Stages 3–5Other important labs
Most relevant:Varies — based on your conditionsYour lab tracker
Type in the labs from your last few visits to see them at a glance and spot the trend. The green/amber/grey shading uses general reference ranges — your team may set personal targets that differ. Nothing is saved or sent; this stays in your browser.
Your lab tracker
Type in your most recent labs to see them at a glance. Reference ranges are general — your care team may set different personal targets. Nothing is saved or sent; this stays in your browser.
| Date | eGFR mL/min | Creatinine mg/dL | Potassium mEq/L | Phosphorus mg/dL | Hemoglobin g/dL | Urine ACR mg/g | PTH pg/mL | Remove this row |
|---|---|---|---|---|---|---|---|---|
Questions for your next visit
- Is my GFR stable, rising, or falling — and over what time period?
- Where would you like my urine albumin to be, and what are we doing to get there?
- Are my mineral and bone labs (phosphorus, calcium, PTH) where you want them?
- Am I anemic, and if so, what’s the workup plan?
- Is bicarbonate at a level where you’d treat the acidosis?
- Which labs should I bring questions about at my next visit?
Related guides
This guide is for education only and doesn't replace advice from your care team.