Kidney inflammation is called nephritis. The term most often refers to glomerulonephritis, where the filtering units (glomeruli) are inflamed, usually by the immune system. Interstitial nephritis, inflammation of the tissue between the tubules, is typically a reaction to a medicine. A bacterial kidney infection (pyelonephritis) is a different problem and is treated with antibiotics.
Nephritis ranges from a mild finding on a urine test to a rapidly progressive illness that can destroy kidney function within weeks. The precise type, usually settled by a kidney biopsy, determines treatment.
Symptoms
- Blood in the urine, either visible (cola or tea coloured) or found only on testing
- Foamy urine from protein loss
- Swelling of the eyelids, ankles or legs
- High blood pressure
- Passing less urine
- Tiredness, poor appetite and nausea as function falls
- Rash, joint pains, fever, sinus problems or coughing up blood when a body-wide disease such as vasculitis or lupus is responsible
Causes and risk factors
IgA nephropathy is the commonest glomerulonephritis worldwide and often shows up as visible blood in the urine during a throat infection. Other types include post-infectious glomerulonephritis 1 to 3 weeks after a streptococcal infection, membranous nephropathy, minimal change disease, focal segmental glomerulosclerosis, lupus nephritis, ANCA-associated vasculitis and anti-GBM disease. Hepatitis B, hepatitis C, HIV and endocarditis can drive it. Interstitial nephritis is most often caused by antibiotics, anti-inflammatory painkillers and stomach acid tablets (proton pump inhibitors).
How it is diagnosed
- Urine dipstick and microscopy: Blood, protein and red cell casts indicate glomerular inflammation; white cells suggest interstitial nephritis.
- Urine protein quantification: A protein or albumin to creatinine ratio; very heavy loss defines nephrotic syndrome.
- Creatinine and eGFR: Repeated over days to weeks to see how quickly function is changing.
- Immunology blood tests: ANA, anti-dsDNA, ANCA, anti-GBM, complement C3 and C4, anti-PLA2R, immunoglobulins, and hepatitis and HIV serology.
- Kidney ultrasound: Checks size and excludes obstruction before biopsy.
- Kidney biopsy: The definitive test: a needle sample under local anaesthetic examined by light microscopy, immunofluorescence and electron microscopy.
Treatment options
- Supportive kidney protection: ACE inhibitor or ARB, SGLT2 inhibitor, salt restriction and blood pressure control underpin care for all chronic types.
- Corticosteroids: Used for minimal change disease, selected IgA nephropathy, interstitial nephritis and as part of combination regimens.
- Immunosuppressants: Cyclophosphamide, mycophenolate, rituximab or calcineurin inhibitors depending on the biopsy diagnosis.
- Newer targeted drugs: Targeted-release budesonide and sparsentan for IgA nephropathy; avacopan in ANCA vasculitis.
- Plasma exchange: For anti-GBM disease and selected severe vasculitis.
- Stopping the offending medicine: The first and most important step in drug-induced interstitial nephritis.
- Diuretics, statins and anticoagulation: For swelling, high cholesterol and clot risk in nephrotic syndrome.
- Dialysis: Temporary or permanent support if the kidneys fail.
When it is urgent
Seek emergency care locally if you cough up blood, pass very little urine, develop sudden severe swelling or breathlessness, a severe headache with very high blood pressure, or one painful swollen leg. Rapidly progressive glomerulonephritis needs treatment within days to save kidney function.
Travelling to Türkiye for treatment
If function is falling quickly, be treated where you are: delay costs nephrons. For stable or unexplained blood and protein in the urine, a visit can deliver a full immunology work-up and a kidney biopsy with expert pathology within about a week, plus a treatment plan. The treatment itself usually runs for 6 to 24 months with frequent blood tests and infection monitoring, so it has to be supervised by a nephrologist near you.
Send your reports, scans and a short history and a Clinic-Y coordinator replies within 24 hours with suitable teams and written, all-inclusive proposals side by side. Reviewing your case is free.
Frequently Asked Questions
Is it the same as a kidney infection?
No. Pyelonephritis is a bacterial infection with fever and flank pain, cured with antibiotics. Glomerulonephritis is immune-mediated and antibiotics do not treat it.
Do I really need a biopsy?
Usually, in adults. Different types look alike on blood and urine tests but need different treatment. The main risk is bleeding, significant in around 1 in 100.
Will it lead to kidney failure?
Some forms resolve fully, such as most post-infectious cases in children. Others progress slowly over decades, and a few are aggressive. Proteinuria, blood pressure and biopsy findings indicate your own risk.
Can it return after a transplant?
Several types can recur in a transplanted kidney, but this causes graft loss in only a minority and rarely rules out transplantation.