Introduction
IgA nephropathy (also called Berger disease) is a kidney condition in which immunoglobulin A (IgA) antibodies deposit in the glomeruli—the tiny filters inside the kidneys. Those deposits trigger inflammation that can slowly reduce the kidneys’ ability to clean blood, control fluid and salt balance, and regulate blood pressure.
The exact trigger is not fully known. Most experts describe a mix of genetic predisposition, immune dysregulation, and environmental or infectious “hits” that set off abnormal IgA production and kidney deposition. Some people have silent urine changes for years; others notice cola-coloured urine during or after a respiratory or gut infection.
It is most often diagnosed between ages 15 and 35 and is more common in males. Rates are higher in parts of Asia and Europe than in some other regions. People with liver disease, coeliac disease, or other autoimmune conditions may have higher risk.
There is no single cure that removes IgA from the kidneys, but many people keep stable kidney function for years with blood-pressure control, protein-sparing therapy, lifestyle measures, and—when needed—immunosuppressive medicines. Early diagnosis and consistent follow-up improve the chance of slowing progression toward chronic kidney disease.
Overview
IgA nephropathy is one of the more common forms of primary glomerulonephritis worldwide. Severity ranges from mild, isolated blood in the urine to progressive protein leak, hypertension, and declining filtration rate.
Diagnosis is confirmed when a kidney biopsy shows IgA-dominant deposits in the mesangium. Blood and urine tests guide monitoring but cannot alone prove IgA nephropathy.
Care goals are to lower proteinuria, protect blood pressure and remaining kidney function, treat complications, and decide whether anti-inflammatory or immunosuppressive therapy is warranted for higher-risk disease.
- IgA antibodies accumulate in kidney filters and cause inflammation
- Exact cause multifactorial—genetic, immune, and environmental factors
- Classic clue: visible or microscopic blood in urine, sometimes with protein
- Definitive diagnosis usually requires kidney biopsy
- Mainstays: ACE inhibitors/ARBs, blood-pressure and lifestyle care; immunosuppression in selected severe cases
- Untreated progressive disease can lead to CKD, kidney failure, and higher cardiovascular risk
What happens in the body
Abnormally glycosylated IgA1 can form immune complexes that deposit in glomerular mesangium. Local complement activation and inflammatory cell recruitment injure capillary walls and the filtration barrier.
Damaged filters leak red cells and protein into urine. Ongoing scarring (glomerulosclerosis and interstitial fibrosis) reduces nephron number, raising blood pressure and creatinine over time. Infections may temporarily amplify immune activity and make hematuria flare.
- Mesangial IgA deposits drive local inflammation and scarring
- Proteinuria and hematuria reflect filtration-barrier injury
- Hypertension both results from and worsens kidney damage
- Infection-linked immune flares can cause episodic cola-coloured urine
Signs and symptoms
Symptoms vary widely; some people have none until urine or blood tests are abnormal. Common possibilities include:
- Hematuria: pink, red, or cola-coloured urine, or blood found only on lab testing
- Proteinuria: excess protein in urine, often found on routine dipstick
- Edema: swelling in legs, ankles, or around the eyes from fluid retention
- High blood pressure developing as kidney regulation worsens
- Fatigue or reduced stamina when kidney function declines
- Flank or abdominal discomfort in some flares
- Episode of dark urine during or soon after a respiratory or gastrointestinal infection
- In advanced disease: nausea, vomiting, confusion, or other uremic symptoms
Causes and risk factors
IgA nephropathy is not caused by one simple lifestyle mistake. Factors commonly discussed include:
- Abnormal IgA immune response with kidney deposition (core mechanism)
- Genetic predisposition or family history of kidney disease in some people
- Respiratory, gastrointestinal, or other viral illnesses that trigger symptom flares
- Autoimmune or related conditions (for example coeliac disease or certain liver diseases) associated with higher risk
- Male sex and young adult age as epidemiologic risk patterns
- Higher prevalence in some Asian and European populations
- High salt intake, obesity, smoking, and heavy alcohol use that worsen overall kidney and blood-pressure health (not proven sole causes)
- Not contagious and not typically blamed on ordinary parenting or vaccines
Diagnosis and evaluation
Evaluation combines history, urine and blood tests, imaging to exclude other problems, and often biopsy for confirmation:
- Detailed history of urine colour changes, infections, family kidney disease, and blood pressure
- Physical exam focusing on edema, blood pressure, and signs of systemic disease
- Urinalysis for blood and protein; quantification of proteinuria when present
- Blood tests of kidney function (creatinine, eGFR, BUN) and related labs
- Kidney ultrasound or CT when needed to assess size/structure and rule out obstruction or other lesions
- Kidney biopsy: microscopic and immunofluorescence exam looking for IgA deposits (definitive in most cases)
- Differential diagnosis versus minimal change disease, FSGS, membranous nephropathy, lupus nephritis, and other glomerulopathies
Treatment and management
Treatment aims to slow progression and control symptoms. Plans are individual—do not start or stop steroids or immunosuppressants on your own:
- ACE inhibitors or ARBs to lower blood pressure and reduce proteinuria
- Additional antihypertensives as needed to reach individualized targets
- Supportive medicines for edema, lipid problems, or other complications
- Corticosteroids or other immunosuppressants for selected higher-risk or rapidly progressive disease under specialist care
- Low-sodium diet rich in vegetables and fruit patterns that support blood pressure
- Regular physical activity and weight management when safe
- Stopping tobacco and limiting excess alcohol
- Pediatric and older-adult plans adjusted for growth, comorbidities, and drug interactions
- Dialysis or transplant planning if kidneys progress to end-stage disease
Prevention, self-care, and lifestyle
Not every condition is fully preventable, but the steps below may lower risk or recurrence:
- No guaranteed way to prevent IgA nephropathy itself
- Stay current with recommended vaccinations to reduce infection-triggered flares where relevant
- Good hygiene and prompt care for significant infections
- Limit salt; favour a kidney-friendly, nutrient-dense eating pattern
- Maintain healthy weight and regular exercise
- Avoid tobacco and excess alcohol
- Control blood pressure early if you already have urine abnormalities or known IgA nephropathy
Possible complications
Delay, missed care, or unsafe self-medication can raise the chance of complications in some cases:
- Progressive chronic kidney disease (CKD)
- Kidney failure requiring dialysis or transplantation
- Acute kidney injury during severe flares or intercurrent illness
- Persistent hypertension and higher risk of heart disease and stroke
- Ongoing proteinuria with edema and nutritional effects
- Medication side effects when immunosuppression is required
When to see a doctor or seek emergency care
Seek prompt medical advice or emergency care if any of the following apply—it is safer not to wait and see:
- New pink, red, or cola-coloured urine, especially with infection symptoms
- Severe or rapidly worsening swelling
- Sudden marked rise in blood pressure
- Sharp drop in urine output
- Severe abdominal or flank pain
- Nausea, vomiting, confusion, or other signs of advanced kidney failure
- Known IgA nephropathy with any rapid change in urine, weight from fluid, or energy
Living with the condition
Many people live full lives with IgA nephropathy when blood pressure, protein leak, and lifestyle measures are managed consistently. Keep scheduled nephrology visits even when you feel well—urine and blood numbers often change before you notice symptoms.
Learn your target blood pressure, bring home readings to visits, and ask which protein or creatinine trends should trigger an earlier appointment. Coordinate colds, new medicines, and imaging contrast exposure with your kidney team.
If disease progresses, early education about CKD stages, dietitian support, and transplant/dialysis options reduces crisis decision-making later.
Frequently asked questions
What are early signs of IgA nephropathy?
Early clues may include blood in the urine, protein on urine tests, and mild swelling. Many people have no obvious symptoms at first and are found through abnormal lab results.
How is IgA nephropathy diagnosed?
Doctors use urinalysis, kidney blood tests, imaging as needed, and usually a kidney biopsy to confirm IgA deposits and guide treatment risk.
Can IgA nephropathy be cured?
There is no cure that permanently clears IgA from the kidneys, but effective management can control symptoms and slow progression for many people.
What lifestyle changes help?
A lower-salt diet, healthy weight, regular activity, not smoking, and limiting excess alcohol support blood pressure and kidney health alongside prescribed medicines.
Is IgA nephropathy hereditary?
A genetic contribution exists in some families, and a family history of kidney disease may raise risk, but inheritance is not a simple single-gene pattern for most patients.
Which medicines are commonly used?
ACE inhibitors or ARBs are common first-line agents. Immunosuppressive drugs are reserved for selected more severe cases under specialist supervision.
How often should I see a doctor?
Follow-up frequency depends on kidney function, protein levels, and blood pressure. Your nephrologist sets a schedule—do not skip monitoring visits.
Can I lead a normal life with IgA nephropathy?
Many people do, especially with early care and adherence to treatment. Activity and work plans are individualized based on kidney stage and complications.
Important caution
This article is general health education in English. It is not personal medical advice, a prescription, or a dialysis/transplant plan.
Decisions about biopsy, blood-pressure drugs, steroids, or immunosuppression should follow evaluation by a qualified clinician.
Seek urgent care for severe swelling, sudden very high blood pressure, marked urine-output change, or symptoms of kidney failure.