Nephrology — Find Specialists & Top Hospitals Worldwide | MyMedicPlus

Nephrology is the medical specialty focused on the diagnosis, treatment, and long-term management of kidney (renal) diseases and their systemic consequences. The kidneys are vital organs that filter waste and excess fluids from the blood, regulate blood pressure, balance electrolytes such as sodium, potassium, and calcium, and produce hormones that stimulate red blood cell production. When kidneys malfunction, consequences ripple across every organ system.

Nephrologists are internal medicine specialists with advanced training in kidney function and renal physiology. They manage the entire spectrum of kidney disease — from early-stage chronic kidney disease (CKD) detected incidentally on blood tests, to end-stage renal disease (ESRD) requiring dialysis or kidney transplantation. Nephrology differs from urology in that urologists treat structural and surgical problems of the urinary tract, while nephrologists focus on the medical management of kidney function and systemic kidney diseases.

Subspecialties within nephrology include transplant nephrology (managing patients before and after kidney transplantation), onco-nephrology (kidney complications of cancer and chemotherapy), interventional nephrology (dialysis access procedures), and glomerular disease. Nephrologists work closely with dietitians, social workers, and transplant coordinators in multidisciplinary kidney care teams.

Nephrologists diagnose and manage a wide range of kidney and related systemic conditions:

• Chronic kidney disease (CKD): Progressive, irreversible reduction in kidney function across five stages, managed to slow progression and prevent complications.
• Acute kidney injury (AKI): Sudden, often reversible decline in kidney function from causes including dehydration, medications, sepsis, or obstruction requiring rapid intervention.
• Glomerulonephritis: Inflammation of the kidney's filtering units (glomeruli), presenting with haematuria, proteinuria, and declining function; causes include IgA nephropathy and lupus nephritis.
• Nephrotic syndrome: Characterised by heavy proteinuria (greater than 3.5 g/day), low albumin, and oedema, with causes including minimal change disease and focal segmental glomerulosclerosis.
• Polycystic kidney disease (PKD): Inherited condition causing progressive cyst development and kidney enlargement, leading to renal failure.
• Diabetic nephropathy: Kidney damage caused by longstanding diabetes, the most common cause of ESRD worldwide.
• Hypertensive nephropathy: Kidney damage from poorly controlled hypertension, managed with ACE inhibitors or ARBs.
• Kidney stones (recurrent or complex): Metabolic evaluation and prevention strategies for patients with recurrent stone formation.
• Renovascular disease: Renal artery stenosis causing secondary hypertension and ischaemic nephropathy.
• Electrolyte and acid-base disorders: Including hyponatraemia, hyperkalaemia, and metabolic acidosis requiring specialist management.

Nephrologists perform and supervise a range of diagnostic and therapeutic procedures specific to kidney and renal replacement care:

• Kidney biopsy: Percutaneous needle biopsy of kidney tissue under ultrasound or CT guidance, the definitive test for diagnosing glomerulonephritis, interstitial nephritis, and unexplained kidney failure.
• Haemodialysis initiation and prescription: Programming and monitoring of the dialysis machine parameters including flow rate, duration, and membrane type to adequately filter blood waste products.
• Peritoneal dialysis catheter insertion: Placing a silicone catheter into the peritoneal cavity for home-based dialysis using the abdominal lining as the filter membrane.
• Tunnelled haemodialysis catheter management: Long-term central venous catheter care for patients requiring temporary or bridge dialysis access.
• AV fistula and graft assessment: Evaluating arteriovenous fistulae created by vascular surgeons for dialysis adequacy and detecting complications such as stenosis.
• Kidney transplant pre-assessment and post-transplant monitoring: Evaluating transplant candidacy, managing immunosuppression, and monitoring for rejection.
• Plasmapheresis: Removing antibodies from blood plasma to treat antibody-mediated kidney diseases such as anti-GBM disease and ANCA vasculitis.

Referral to a nephrologist is indicated in these clinical situations:

• Reduced kidney function: eGFR below 45 mL/min/1.73m² (CKD Stage 3b or worse) warrants nephrology consultation; eGFR below 30 requires active co-management.
• Significant proteinuria: Urine protein-to-creatinine ratio above 100 mg/mmol (approximately 1 g/g) or albuminuria above 300 mg/day requires evaluation for glomerular disease.
• Unexplained haematuria: Blood in urine with concurrent reduced kidney function or proteinuria points to a glomerular cause needing nephrology assessment.
• Refractory or secondary hypertension: Blood pressure uncontrolled despite three medications, or hypertension with kidney involvement, warrants specialist review.
• Acute kidney injury not resolving: Creatinine failing to return to baseline within 48–72 hours, or AKI requiring dialysis.
• Electrolyte disorders: Persistent hyperkalaemia, hyponatraemia, or metabolic acidosis not responsive to primary care management.
• Approaching dialysis: Patients with CKD Stage 4 should be referred to plan renal replacement therapy modality and timing.
• Kidney transplant evaluation: Assessing fitness for transplantation and managing waitlist criteria.

Nephrologists undergo rigorous, multi-year specialised training. In the United States, the pathway begins with a four-year medical degree (MD or DO), followed by a three-year internal medicine residency during which trainees develop broad adult medicine competency. This is followed by a two-year nephrology fellowship at an accredited training program, where fellows rotate through haemodialysis and peritoneal dialysis units, kidney transplant services, outpatient renal clinics, and kidney biopsy services. Transplant nephrology subspecialists complete an additional one-year fellowship at a transplant centre with high organ volume.

Board certification in nephrology is awarded by the American Board of Internal Medicine (ABIM) upon passing the nephrology certifying examination. Equivalent credentialing bodies exist internationally, including the Royal College of Physicians in the UK (MRCP plus nephrology CCT) and similar bodies in Canada, Australia, and India. Continuing medical education and recertification maintain competency throughout a nephrologist's career, particularly as new treatments such as SGLT-2 inhibitors for CKD and novel dialysis modalities continue to emerge.

Referral to a nephrologist typically comes from your GP or internist based on abnormal kidney blood tests (elevated creatinine, reduced eGFR) or urinalysis findings (protein or blood in urine). When seeing a nephrologist for the first time, bring all recent kidney function blood tests (ideally from the past one to two years), urine test results, a full medication list including supplements, your blood pressure readings, and any relevant imaging such as kidney ultrasound reports.

Patients with CKD Stages 4 to 5 are best managed by a multidisciplinary kidney team that includes a nephrologist, renal dietitian, renal nurse educator, social worker, and transplant coordinator. Ask your nephrologist about the timing of dialysis access creation (AV fistula), home dialysis options, and kidney transplant waitlist evaluation well before dialysis becomes urgent.