Quick Navigation
- What Is Glomerulonephritis?
- Acute vs Chronic Glomerulonephritis: What Is the Difference?
- What Are the Symptoms of Glomerulonephritis?
- What Causes the Kidney's Filters to Become Inflamed?
- How Is Glomerulonephritis Diagnosed?
- How Is Glomerulonephritis Treated?
- When Should You See a Doctor?
- How Do You Protect Your Kidneys Long Term?
- Frequently Asked Questions
Glomerulonephritis is inflammation of the glomeruli, the tiny filters inside the kidneys. When they are inflamed, blood and protein leak into the urine while waste and fluid build up, causing cola-coloured or foamy urine, puffy eyes or ankles and high blood pressure. It can follow an infection or an autoimmune condition, and it needs a nephrologist's assessment.
Glomerulonephritis sounds complicated, but the idea behind it is simple. Each kidney contains about a million tiny filters called glomeruli. When they become inflamed, they stop working cleanly. Waste and extra fluid build up in the body. Protein and red blood cells, which should stay in the blood, leak into the urine.
It can come on suddenly, often a week or two after an infection, or build quietly over years. This guide covers the symptoms, the causes, how doctors confirm it, and what treatment and follow-up involve.
Key Takeaways
- Glomerulonephritis is inflammation of the kidney's filters (glomeruli). It is not a kidney infection; the two have different causes.
- The classic signs are cola or tea-coloured urine, foamy urine, puffiness around the eyes or ankles, raised blood pressure and tiredness.
- It can be acute (sudden, often after a throat or skin infection, especially in children) or chronic (slow and silent until kidney function has already dropped).
- Diagnosis starts with urine and blood tests and an ultrasound; a kidney biopsy is sometimes needed to identify the exact type.
- Treatment depends on the cause and is decided by a nephrologist. Many people keep stable kidney function for years with good blood pressure control and follow-up.
What Is Glomerulonephritis?
Think of each glomerulus as a tiny sieve. Blood passes through it under pressure. Water and waste go one way to become urine; blood cells and large proteins stay behind. Inflammation damages the sieve. It then lets through what it should hold back, and holds back what it should let go. That single fault, kidney filter inflammation, explains almost every symptom in this article.
Glomerulonephritis is not a kidney infection. A kidney infection (pyelonephritis) is caused by bacteria and brings fever and back pain. Glomerulonephritis is also not one disease but a family of them, grouped by the trigger and by how quickly it happens.
Acute vs Chronic Glomerulonephritis: What Is the Difference?
Doctors describe two broad patterns. Knowing which one you have shapes everything from urgency to outlook.
| Feature | Acute glomerulonephritis | Chronic glomerulonephritis |
|---|---|---|
| How it starts | Suddenly, over days | Slowly, over months or years |
| Typical trigger | A recent infection, classically a streptococcal throat or skin infection | Immune conditions, long-standing damage; often no clear trigger |
| Who | More often children and young adults | More often adults |
| Symptoms | Dark urine, puffiness, high blood pressure, less urine | Few or none until kidney function has already declined; picked up on tests |
| Outlook | Many recover fully, especially children, once the trigger settles | Needs long-term management to slow further damage |
Both need proper medical attention. The acute form is easier to spot. The chronic form is the one that gets missed, which is why an unexplained abnormal urine test should never be filed away.
What Are the Symptoms of Glomerulonephritis?
Not everyone notices glomerulonephritis symptoms early, especially with the chronic form. When they do appear, they follow directly from the leaky-filter problem:
- Urine that looks dark, cola-coloured or tea-coloured, from blood
- Foamy or bubbly urine that does not settle, from protein
- Puffiness around the eyes on waking, or swelling of the ankles, feet or hands
- Raised blood pressure, sometimes the only early sign
- Tiredness, poor appetite or reduced energy
- Passing less urine than usual in some cases
The urine changes are the earliest clue most people can see. Our explainers on what blood in urine can mean and why urine turns foamy cover the other causes. When the two occur together with swelling or high blood pressure, the kidney's filters move to the top of the list.
In children, the acute form often follows a sore throat or a skin infection by a week or more. A child who develops dark urine, puffy eyes or reduced urine output after such an illness should see a paediatrician promptly.
What Causes the Kidney's Filters to Become Inflamed?
The common thread is the immune system. Either it reacts to an infection and the reaction spills over onto the glomeruli, or it targets the kidney directly. The main groups are:
- Infections: classically post-streptococcal illness, but other bacterial and viral infections can trigger it too.
- Immune and autoimmune conditions: IgA nephropathy (the commonest type worldwide), lupus, and rarer disorders such as Goodpasture syndrome.
- Other kidney diseases: certain forms of vasculitis (inflamed blood vessels) and scarring conditions.
- Unknown causes: in some people no clear trigger is ever found.
In a few families it runs in the genes, but most cases are not inherited. You cannot catch it from someone else.
How Is Glomerulonephritis Diagnosed?
The work-up is stepwise, and the early steps are simple:
- Urine tests to look for red blood cells, protein and casts (tiny moulds of the kidney tubules that point to the filters).
- Blood tests for kidney function (creatinine, eGFR), plus tests for recent streptococcal infection or autoimmune markers when relevant.
- Blood pressure measurement, which is part of the diagnosis, not an afterthought.
- An ultrasound to check the size and appearance of the kidneys.
- A kidney biopsy in selected cases: a small sample taken with a needle under local anaesthetic, to identify the exact type and guide treatment.
Which of these you need, and in what order, is a decision for a nephrologist, the kidney specialist. If your family doctor has found blood and protein in urine on the same test, that referral is the right next step.
How Is Glomerulonephritis Treated?
Treatment depends on the cause, whether the condition is acute or chronic, and how much the kidneys are affected. Rather than a single cure, it is usually a combination:
- Treating the trigger, for example antibiotics if an active bacterial infection is still present.
- Blood pressure medicines that also reduce protein leakage from the filters.
- Fluid tablets (diuretics) to ease swelling, and advice on salt and fluid intake.
- Medicines that calm the immune system when it is driving the inflammation; the choice and duration are individual and closely monitored by the nephrologist.
- In advanced cases, dialysis, and planning for a kidney transplant where appropriate.
Early treatment protects the kidney function you still have. In many acute cases it allows a full recovery. Dialysis is only needed if kidney function has fallen a long way, and when it is, haemodialysis is a well-established treatment, not the end of the road.
When Should You See a Doctor?
See a doctor within a few days if you notice any of these:
- Dark or cola-coloured urine
- Foamy urine that keeps happening
- New puffiness around the eyes or ankles
- Blood pressure suddenly higher than usual
- A routine urine test showing blood or protein
Ask for kidney function tests, and for a nephrology referral if anything is abnormal.
Get urgent care today if
- You are passing very little or no urine
- You are breathless or cannot lie flat because of fluid build-up
- You have a severe headache or blurred vision with very high blood pressure
- Dark urine and swelling appear in a child after a recent throat or skin infection
- Kidney function can fall quickly in acute glomerulonephritis, and a sudden drop needs hospital care
A rapid decline in kidney function is treated as acute kidney injury, which often recovers well when caught early. If in doubt, go to the nearest emergency department rather than waiting for a clinic slot.
How Do You Protect Your Kidneys Long Term?
Once glomerulonephritis is diagnosed, regular follow-up is the most useful thing you can do. Keep blood pressure in range, take medicines as prescribed, do not smoke, and treat infections promptly; all of these slow further damage. Less salt and a sensible protein intake help too, but specific diet advice should come from your kidney team, not a generic list.
Women planning a pregnancy should discuss it with their nephrologist first, since the condition and some of its medicines need planning. With the right monitoring, many people with glomerulonephritis live full, active lives and never need dialysis.
Glomerulonephritis is serious, but nephrologists understand it well and can usually manage it. Notice a change in urine colour or foam, unexplained swelling or a rising blood pressure, and get it tested rather than watched. That is where good outcomes begin.
Frequently Asked Questions
Is glomerulonephritis the same as a kidney infection?
No. A kidney infection (pyelonephritis) is caused by bacteria and usually brings fever and back pain. Glomerulonephritis is inflammation of the filters themselves, driven by the immune system, with different causes and treatment.
Can children get glomerulonephritis?
Yes. The acute form that follows a streptococcal throat or skin infection is more common in children, and most recover fully with supportive care and follow-up.
Does foamy urine always mean kidney disease?
No. Occasional foam, especially with a fast stream or concentrated urine, is normal. Persistent heavy foam that does not settle should be tested, because it can mean protein is leaking from the filters.
Can glomerulonephritis go away on its own?
Some acute cases linked to infection improve once the infection settles, but they still need monitoring. Chronic forms usually need long-term management rather than resolving on their own.
Is high blood pressure a cause or a result?
Both. Glomerulonephritis often raises blood pressure, and high blood pressure then damages the kidneys further, which is why controlling it is central to treatment.
Will I definitely need dialysis?
No. Many people keep stable kidney function for years with good treatment. Dialysis is only needed if kidney function falls significantly, and even then a transplant may be an option later.
Can diet help?
Yes. Less salt, a healthy weight and your team's advice on protein all support the kidneys. Ask your nephrologist or a renal dietitian for specific targets rather than following generic advice online.
Is glomerulonephritis contagious?
No. You cannot catch it from another person. The infections that sometimes trigger it, such as a strep throat, can spread, but the kidney reaction itself cannot.
Are there different types of glomerulonephritis?
Yes. IgA nephropathy, post-streptococcal glomerulonephritis and lupus nephritis are common examples, and there are several others. The exact type, often confirmed by biopsy, guides treatment.
Can pregnancy be affected?
Yes. Women with glomerulonephritis need planning and specialist care before and during pregnancy, because blood pressure, kidney function and some medicines all need attention.
Blood or protein on your urine report?
A nephrologist can tell whether the kidney's filters are involved and what to do next.
Get Your Kidneys Checked by a Specialist
Book a nephrology consultation at Unittas Hospital, Chennai. Bring your urine report, blood pressure readings and any kidney function results you already have.