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Kidney function test in Lucknow: creatinine, eGFR and the test everyone skips
· 6 min read · Lucknow
Chronic kidney disease is common in India, closely tied to the diabetes and hypertension that are common alongside it, and it is almost entirely silent until it is advanced. There is usually no pain, no change in urine, and no symptom to prompt a test.
That silence is the whole problem, and it is why screening the right people matters far more here than waiting for something to feel wrong.
What the blood tests show — and their blind spot
Creatinine is a waste product from muscle that healthy kidneys clear. As filtration falls, creatinine rises. But it depends on muscle mass, which is why the same value can mean different things in a heavily built young man and a slight elderly woman.
eGFR corrects for that by estimating filtration rate from creatinine along with age and sex, and it is the more meaningful number. It is the one to look for on your report.
The blind spot is important: creatinine often stays within the normal range until a substantial proportion of kidney function is already lost. A normal creatinine is genuinely reassuring, but it is not the same as proof that the kidneys are entirely well.
The urine test that finds it earlier
Urine albumin-creatinine ratio, usually written ACR, detects small amounts of albumin leaking into urine — often the earliest sign of kidney damage, appearing well before creatinine moves at all.
It is inexpensive, needs only a spot urine sample, and is repeatedly under-ordered. For anyone with diabetes or hypertension it should be an annual test alongside the bloods. A raised ACR is also a cardiovascular risk marker in its own right, so its usefulness extends beyond the kidneys.
- Diabetes — annual eGFR and urine ACR, without waiting for symptoms
- Hypertension — the same, annually
- A family history of kidney disease
- Long-term use of painkillers, particularly NSAIDs
- Recurrent kidney stones or repeated urinary infections
- Age over 60, as part of a routine panel
Before you test, and what a result means
Creatinine rises transiently after heavy exercise, a high-protein meal or creatine supplements, and with dehydration. Avoid strenuous exercise the day before, be normally hydrated, and mention any supplements — an abnormal result that was really a gym session wastes a scan and a fortnight of worry.
A single abnormal result is not a diagnosis. Chronic kidney disease is defined by abnormality persisting over three months, so a repeat is standard. What matters most is the trend, and catching it early enough that controlling blood pressure and sugar can genuinely slow the decline.
This article is general health information, not a diagnosis or a treatment plan. Test results are read alongside your symptoms and history — please discuss yours with your doctor. See our disclaimer.
