Glomerulonephritis (often shortened to GN) is inflammation of the glomeruli — the microscopic filtering units inside the kidney. It is not one disease but a group of conditions that share the same site of injury. The exact type matters a great deal, because what causes the inflammation, how quickly it progresses, and how it is treated all differ from one form to another.
How the glomeruli work
Each kidney contains roughly a million nephrons. At the head of every nephron sits a glomerulus: a knot of capillaries held inside a cup-shaped capsule. Blood arrives under pressure, and water, salts and small waste molecules are pushed through the capillary wall into the capsule, while blood cells and large proteins are held back. What passes through goes on to become urine; what is retained returns to the circulation.
That filter is selective, and that is exactly why damage to it shows up so clearly in a urine test. When the glomerular wall becomes inflamed, red blood cells and protein leak into the urine — the two findings that most often bring a patient to a nephrologist in the first place.
Types of glomerulonephritis
By course
- Acute glomerulonephritis develops over days to weeks, frequently after an infection, and may settle with treatment.
- Rapidly progressive glomerulonephritis is the most urgent form. Kidney function can fall within weeks, and a biopsy usually shows crescent formation in the glomeruli. How early it is recognised has a strong bearing on the outcome.
- Chronic glomerulonephritis develops slowly and may cause few symptoms for years while kidney function declines gradually.
By cause
- Primary — the kidney is the main target. IgA nephropathy and membranous nephropathy belong to this group.
- Secondary — the kidney is caught up in a disease that begins elsewhere, such as lupus, IgA vasculitis (Henoch-Schönlein purpura) or a systemic vasculitis.
What causes it
In most forms the underlying mechanism is immune: antibodies or immune complexes settle in the glomeruli and set off inflammation. Recognised triggers and associations include:
- Infection — streptococcal throat or skin infection, hepatitis B or C, HIV, malaria and others
- Autoimmune disease — systemic lupus erythematosus, ANCA-associated vasculitis, anti-GBM disease
- Medications and toxins — certain antibiotics, NSAIDs, gold salts and some contrast agents
- Malignancy — some solid tumours and lymphoproliferative disorders
- Heredity — a minority of cases run in families
For many patients no trigger is ever identified. That does not make the diagnosis any less real, and it does not change the fact that the condition can be assessed, monitored and treated.
Symptoms
Early signs
- Blood in the urine — urine may look cola-coloured, tea-coloured, or simply show blood on testing
- Frothy urine — a sign that protein is passing through the filter
- Swelling — typically around the eyes on waking, and in the ankles or legs later in the day
- Raised blood pressure — sometimes the first abnormality noticed
- Passing less urine than usual
- Tiredness that does not match the patient's usual level of activity
Signs that kidney function is declining
- Loss of appetite, nausea, or an altered taste for food
- Itching without a rash
- Muscle cramps, particularly at night
- Shortness of breath or swelling that is getting worse
- Difficulty concentrating
None of these symptoms is specific to glomerulonephritis on its own. What matters is the pattern, and what the urine and blood tests show.
How it is diagnosed
Tests you can expect
- Urine analysis — dipstick and microscopy, looking for blood, protein and red cell casts
- Urine protein quantification — a protein-to-creatinine ratio on a spot sample, or a 24-hour collection
- Blood chemistry — creatinine, eGFR, urea, electrolytes and albumin
- Immunology — complement C3 and C4, ANA, anti-dsDNA, ANCA, anti-GBM antibodies, and infection serology where relevant
- Imaging — ultrasound to assess kidney size, shape and structure
- Kidney biopsy — where the diagnosis or the severity remains unclear
Understanding your results
| Test | What it reflects | Common reference range |
|---|---|---|
| eGFR | Overall filtering capacity of the kidneys | 90 mL/min/1.73 m² or above |
| Urine protein-to-creatinine ratio | How much protein is leaking through the filter | Below 30 mg/mmol |
| Urine red blood cells | Inflammation or damage in the glomerulus | 0–2 per high-power field |
| Serum albumin | Protein stores; falls when protein loss is heavy | 35–50 g/L |
| Complement C3 / C4 | Activity of part of the immune system | 0.9–1.8 g/L / 0.1–0.4 g/L |
Reference ranges differ slightly between laboratories. Always read your results against the ranges printed on your own report.
What a biopsy adds
A biopsy is a small sample of kidney tissue, usually taken with a fine needle under ultrasound guidance. It shows which part of the glomerulus is inflamed, whether there is scarring, and whether crescents are present. For some conditions — rapidly progressive disease in particular — this information is what decides the treatment.
Treatment principles
Treatment is built around the individual diagnosis, but the same few aims apply in almost every case.
1. Protect the kidney day to day
- Keep blood pressure within the target your physician sets
- Follow the salt and protein guidance given by your dietitian rather than a general diet
- Avoid NSAID painkillers and other drugs that are hard on the kidney
- Treat infections promptly and keep vaccinations up to date
2. Address the underlying cause
When the trigger is an infection, an autoimmune disease or a medication, treating or removing it is the first step. In secondary forms, controlling the systemic disease is central to protecting the kidney.
3. Reduce protein loss
Blood-pressure-lowering drugs of the ACE inhibitor or ARB class reduce pressure inside the glomerulus and lower protein leakage. They are often used even when blood pressure is normal, because the effect on the filter is the point.
4. Calm the immune response
Where the immune system is driving the damage — lupus nephritis, vasculitis, anti-GBM disease — immunosuppression is used. Depending on the condition this may include corticosteroids, cyclophosphamide, mycophenolate, rituximab, or plasma exchange. These treatments carry real risks and are dosed and monitored carefully.
5. Manage complications
Swelling, high blood pressure, electrolyte disturbance, anaemia and, in advanced cases, the need for blood purification are treated alongside the glomerular disease itself.
Where Chinese medicine fits
At our hospital, Chinese medicine is used alongside standard nephrology care, not instead of it. The hospital works within an integrated Chinese-Western model: a conventional nephrology diagnosis is established first, and a Chinese medicine pattern assessment is made alongside it. Herbal prescriptions are then considered for the individual patient.
Two practical points are worth stating plainly. First, herbal formulas can interact with immunosuppressants, antihypertensives and diuretics, so any prescription has to be reviewed against the medication a patient is already taking. Second, patients who arrive on dialysis or whose kidney function has already fallen a long way need an honest conversation about what treatment can and cannot be expected to achieve. Our specialists give that assessment in writing after reviewing the case.
Outlook and follow-up
The outlook varies widely. Some forms of acute glomerulonephritis resolve with treatment. Others are chronic and need years of monitoring. Two factors make the largest difference: identifying the exact type of glomerulonephritis early, and controlling blood pressure and protein loss consistently over time.
Follow-up usually means regular urine and blood testing, medication review, and periodic reassessment of kidney function. Patients who keep these appointments tend to have fewer surprises.
Questions patients ask us
Can glomerulonephritis be cured?
Some forms resolve completely. Others are controlled rather than cured — the aim is to preserve kidney function and prevent progression. Your nephrologist can tell you which category your diagnosis falls into.
Will I need dialysis?
Most people with glomerulonephritis never need dialysis. The risk depends on the specific type, how much function was lost before diagnosis, and how well the condition responds to treatment.
Do I need a biopsy?
Not always. A biopsy is recommended when the urine and blood results do not identify the type clearly, or when the disease is progressing quickly and treatment decisions are urgent.
Can I travel to Qingdao for treatment?
Yes. Send your reports to our international department and a specialist panel will review the case and give you a written opinion before you commit to anything. There is no charge for that review and no obligation to travel.