1. About you

Age years

Sex

Male Female

Date of this test

Height cm · needed under 18

Weight kg · for medicine doses

Conditions

Diabetes High blood pressure

2. Blood and urine results

Serum creatinine

Cystatin C mg/L · optional, more accurate in Indians

Urine protein test

ACR

"mg/g creatinine" and "mcg/mg" are the same as mg/g. A "urine microalbumin" in mg/L alone is not a ratio: look for the ratio on the report.

Potassium mmol/L · optional

Earlier creatinine results (for the trend)

Add past results with their dates. Use the same unit as above. Age at each date is worked out for you.

Anything that makes creatinine less reliable?

Very thin, frail or undernourished Very muscular, body building Creatine or protein supplements Vegetarian or low-protein diet Amputation or spinal cord injury Cirrhosis, heart failure, cancer, muscle wasting Obesity Recently unwell, dehydrated, or creatinine changing fast Pregnant

For doctors: referral and treatment details

ACE inhibitor/ARB, SGLT2 inhibitor or finerenone started or increased in the last 3 months Albuminuria confirmed on a repeat sample Red cell casts, or RBC over 20 per HPF, not explained BP not controlled on 4 or more medicines Recurrent or extensive kidney stones Known or suspected hereditary kidney disease Cause of CKD uncertain (for example, no diabetic retinopathy, sudden albuminuria) Anaemia, acidosis, bone-mineral disease or malnutrition from CKD Albuminuria has doubled on follow-up

Your eGFR

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Stage

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Risk level

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Where you are on the kidney risk chart

Equations

Equation	Result	Use

KDIGO category and monitoring

Kidney failure risk (KFRE, 4-variable)

Trend

Referral to nephrology (KDIGO 2024)

Medicines at this level of kidney function

Generic names. Label thresholds use eGFR unless marked CrCl (Cockcroft-Gault). Rows needing a change or caution at this level are highlighted. Check the current label before prescribing.

Medicine	At this patient's level	Rule

Monitoring after starting kidney-protective treatment

ACE inhibitor or ARB: check BP, creatinine and potassium 2 to 4 weeks after starting or increasing. Continue unless creatinine rises by more than 30% within 4 weeks.
SGLT2 inhibitor: an early, reversible dip in eGFR is expected and is not a reason to stop. Continue even if eGFR falls below 20, until dialysis or transplant.
Finerenone: check potassium at 4 weeks after starting or any dose change, then regularly.
Sick-day rule: during vomiting, diarrhoea or poor intake, pause metformin, SGLT2 inhibitors, ACE inhibitor/ARB, diuretics and NSAIDs, and restart 24 to 48 hours after eating and drinking normally.
Iodinated contrast: with eGFR below 60, hold metformin at the time of the scan and recheck eGFR at 48 hours before restarting.

About accuracy in Indian patients

In 412 Indian adults with measured GFR (Yadav et al., Kidney International Reports 2024), creatinine-based CKD-EPI 2021 overestimated GFR by about 19 mL/min/1.73m² on average, and only 41% of estimates were within 30% of measured GFR. Cystatin C alone was within 30% in 61%, and the combined equation in 55%. Lower muscle mass and vegetarian diets are the likely reasons. When a decision turns on the number (starting or stopping a medicine, referral, a borderline stage), a cystatin C level is worth ordering.

Understanding the numbers

What eGFR is

eGFR (estimated glomerular filtration rate) is how much blood your kidneys clean each minute, estimated from a blood test. A healthy young adult is usually above 90. It falls slowly with age. It is an estimate: muscle, diet and illness move creatinine, which is why a second marker, cystatin C, is sometimes added.

What the urine test adds

The albumin-creatinine ratio (ACR) looks for albumin leaking into the urine. In diabetes it is often the first sign of kidney damage, years before eGFR falls, and it is the part that treatment can bring down. Below 30 mg/g (3 mg/mmol) is normal. 30 to 299 is moderately increased. 300 or more is severely increased. Because exercise, fever, a urine infection or very high sugars can raise it for a day, a raised result is repeated, ideally on an early-morning sample.

Why one test is not a diagnosis

Chronic kidney disease means an eGFR below 60, or signs of kidney damage such as albumin in the urine, lasting more than three months. A single low value after a fever, dehydration or a new medicine may recover. Repeat it before drawing conclusions.

Sources

Inker LA, et al. New creatinine- and cystatin C-based equations to estimate GFR without race. N Engl J Med 2021. Coefficients as published by NIDDK.
KDIGO 2024 Clinical Practice Guideline for the Evaluation and Management of CKD. kdigo.org
KDIGO 2022 Clinical Practice Guideline for Diabetes Management in CKD. kdigo.org
Pierce CB, et al. Age- and sex-dependent clinical equations to estimate GFR in children and young adults with CKD (CKiD U25). Kidney Int 2021;99:948.
Tangri N, et al. Multinational assessment of the Kidney Failure Risk Equation. JAMA 2016. kidneyfailurerisk.com
Yadav AK, Jha V, et al. Performance of GFR estimating equations in Indians. Kidney Int Rep 2024. ScienceDirect
Prescribing information: metformin, dapagliflozin, empagliflozin, canagliflozin, finerenone, sitagliptin, saxagliptin, alogliptin (US labels); vildagliptin, gliclazide, acarbose (UK SmPCs); teneligliptin (Indian prescribing information); insulin icodec (EU SmPC).

Found an error? Write to info@caspianhealthcare.in. Kidney diet guidance for clinicians: diet in CKD with diabetes.

eGFR and kidney disease calculator