How Kidneys Fail: Understanding Chronic Kidney Disease

The kidneys are two bean-shaped organs that filter about 200 litres of blood every day, removing waste products and excess fluid as urine. They also regulate blood pressure, produce red blood cells (via erythropoietin), and maintain the balance of minerals in the blood.

Chronic kidney disease (CKD) is a gradual loss of kidney function over months or years. It is classified in 5 stages based on the glomerular filtration rate (GFR) — a measure of how well the kidneys are filtering. Stage 5 (GFR below 15) is called end-stage renal disease (ESRD) — the kidneys have lost 85–90% of their function and the patient requires dialysis or a kidney transplant to survive.

• Diabetes mellitus — the leading cause of kidney failure worldwide; high blood sugar damages the kidney's filtering units (glomeruli)
• Hypertension (high blood pressure) — the second most common cause; damages blood vessels in the kidneys
• Glomerulonephritis — inflammation of the kidney's filtering units; can be autoimmune or infection-related
• Polycystic kidney disease (PKD) — a genetic condition where cysts replace normal kidney tissue
• Recurrent kidney infections (pyelonephritis) — chronic infection causing scarring
• Obstructive uropathy — blockage of urine flow (kidney stones, enlarged prostate) causing back-pressure damage
• Lupus nephritis — kidney damage caused by the autoimmune disease lupus

Symptoms of Kidney Failure

CKD is often called a "silent" disease because symptoms are minimal until the kidneys have lost 60–70% of their function. By the time symptoms appear, the disease is usually advanced.

• Fatigue and weakness — kidneys are not removing waste products from the blood
• Swelling (oedema) of the legs, ankles, and face — fluid retention
• Shortness of breath — fluid accumulating in the lungs
• Decreased urine output or no urine at all
• Foamy or bubbly urine — protein leaking into the urine
• Blood in urine (haematuria)
• Persistent nausea, vomiting, and loss of appetite
• Itching all over the body (uraemic pruritus) — waste products depositing in the skin
• Muscle cramps and restless legs
• High blood pressure that is difficult to control

The Kidney Transplant Operation

A kidney transplant places a healthy kidney from a donor into the recipient's lower abdomen (pelvis). The diseased kidneys are usually left in place — they are only removed if they are causing problems (infection, uncontrolled hypertension, or are very large in PKD).

The donor kidney's blood vessels are connected to the recipient's iliac vessels (in the pelvis), and the ureter (the tube from the kidney to the bladder) is connected to the recipient's bladder. The new kidney usually starts producing urine within minutes to hours of being connected.

• Living donor transplant: a family member or compatible donor donates one kidney; they live normally with one kidney
• Deceased donor transplant: kidney from a brain-dead donor; waiting time in India is shorter than in Western countries
• Surgery duration: 3–4 hours for the recipient; 2–3 hours for the living donor
• Compatibility testing: blood group, HLA tissue typing, and crossmatch test must be compatible
• Immunosuppressants: tacrolimus, mycophenolate, and steroids prevent rejection — taken for life
• Dialysis: most patients can stop dialysis within days of a successful transplant

Life After Kidney Transplant

A successful kidney transplant dramatically improves quality of life. Most patients feel the difference within days — energy returns, swelling reduces, and the need for dialysis ends. The 1-year graft survival rate at India's top centres is over 95%.

Patients must take immunosuppressant medications every day for life and attend regular follow-up appointments. With proper care, a transplanted kidney can function for 15–20+ years.

• Hospital stay: 10–14 days after transplant
• Overseas patients: stay in India for 4–6 weeks for close monitoring before flying home
• Diet: low-potassium, low-phosphorus diet in the first few months; gradually liberalised
• Avoid raw/undercooked food and crowded places for the first 3–6 months
• Annual cancer screening — immunosuppressants increase risk of skin cancer and lymphoma
• Blood tests: weekly for the first month, then monthly, then every 3 months
• Return to work: most patients return to desk jobs within 2–3 months