Chronic Kidney Disease: An Evidence-Based Overview
What chronic kidney disease is, how it is diagnosed and staged, and how it is managed — an overview from the Department of Nephrology, CMC Vellore.
Last updated: 2026-09-24
Chronic kidney disease (CKD) is the gradual and usually permanent loss of kidney function over months or years. Because the kidneys have considerable reserve capacity, the condition typically causes no symptoms until it is well advanced, which is why screening based on risk factors matters more than waiting for symptoms.
What the kidneys do
The kidneys filter waste and excess fluid from the blood, regulate blood pressure, activate vitamin D for bone health, and produce erythropoietin, a hormone that drives red blood cell formation. Loss of these functions explains much of what is seen clinically in CKD.
Common causes
- Diabetes — the leading cause of kidney failure in India
- High blood pressure
- Glomerulonephritis (inflammation of the kidney filters)
- Obstructive conditions such as recurrent stones or an enlarged prostate
- Some inherited and autoimmune conditions
Diagnosis and staging
CKD is confirmed by a blood test for creatinine, from which an estimated glomerular filtration rate (eGFR) is derived, together with a urine test for protein. The disease is staged from 1 to 5 according to eGFR, and the urine protein result is used alongside the stage to estimate risk of progression.
A single abnormal result does not confirm CKD. The diagnosis requires abnormality persisting for at least three months, which is why a repeat test is standard rather than a sign of uncertainty.
Frequently asked questions
Can chronic kidney disease be cured?
Most CKD cannot be reversed, but its progression can often be slowed substantially with blood-pressure and blood-sugar control, medication, and diet. Early detection is the strongest determinant of outcome.
Is CKD the same as kidney failure?
No. Kidney failure (stage 5) is the advanced end of CKD, when the kidneys function below about 15% of normal and dialysis or transplantation is usually required.