Glomerulonephritis

Glomerulonephritis is inflammation of the glomeruli, the tiny filtering units inside the kidneys that remove waste and extra fluid from the blood. It can appear suddenly or develop slowly, and early specialist care helps protect kidney function.

Overview

Glomerulonephritis is a group of kidney diseases in which the glomeruli become inflamed. Glomeruli are microscopic filters that clean the blood by removing waste products, excess salt and extra fluid while keeping useful substances such as blood cells and proteins in the circulation. When these filters are inflamed, they can leak blood or protein into the urine and may not remove waste as efficiently.

Glomerulonephritis may be acute, meaning it begins suddenly, or chronic, meaning it develops gradually over months or years. Some people notice changes such as dark or foamy urine, swelling or high blood pressure. Others have no obvious symptoms at first, and the condition is found during routine urine or blood tests.

The outlook depends on the underlying cause, how much kidney function is affected and how early treatment begins. Many forms can be managed effectively with careful monitoring and specialist care. The main goals are to control inflammation, protect kidney function, manage blood pressure and reduce the risk of long-term kidney damage.

Symptoms

Glomerulonephritis symptoms vary widely. Mild disease may cause no noticeable problems, while more active inflammation can cause changes in urine, fluid balance and blood pressure. Symptoms can appear quickly after an infection or develop slowly over time.

Common signs and symptoms may include:

• Pink, red, brown or cola-colored urine caused by blood in the urine
• Foamy or bubbly urine, which may suggest excess protein in the urine
• Swelling around the eyes, face, feet, ankles or hands
• High blood pressure or headaches related to raised blood pressure
• Reduced urine output in some acute cases
• Tiredness, nausea or poor appetite when kidney function is reduced
• Shortness of breath if fluid builds up in the body

Children may present with puffiness around the eyes, darker urine or swelling after a throat or skin infection. Adults may first learn they have glomerulonephritis after urine testing shows blood or protein, or after blood tests show reduced kidney filtration. Because symptoms are not specific, medical testing is needed to confirm the cause.

Causes & Risk Factors

Glomerulonephritis can occur when the immune system injures the kidney filters. In some cases, this follows an infection; in others, it is linked to an autoimmune condition in which the immune system mistakenly attacks the body. Sometimes the disease is limited mainly to the kidneys, and sometimes it is part of a wider condition affecting other organs.

Possible causes and associated conditions include infections, immune-mediated kidney diseases, systemic autoimmune disorders, certain blood vessel inflammation disorders, inherited kidney filter problems and some chronic infections. A previous sore throat or skin infection can occasionally be followed by acute kidney inflammation. Conditions such as lupus or vasculitis can also affect the glomeruli.

Risk factors may include a personal or family history of kidney disease, autoimmune disease, recurrent infections, certain genetic conditions, uncontrolled high blood pressure or exposure to factors that can stress the kidneys. However, many patients have no obvious risk factor. Identifying the cause is important because treatment differs greatly between types of glomerulonephritis.

Diagnosis

Diagnosis begins with a medical history, physical examination and blood pressure measurement. The doctor asks about urine changes, swelling, recent infections, medicines, family kidney history and symptoms that may suggest autoimmune disease, such as joint pain, rash or unexplained fever. Examination may look for swelling, signs of fluid overload and evidence of high blood pressure.

Urine tests are central to diagnosis. A urine dipstick and microscopic examination can detect blood, protein and abnormal cell casts that point to inflammation in the kidney filters. The amount of protein in the urine may be measured to help assess severity and guide follow-up.

Blood tests are used to evaluate kidney function, estimate filtration rate, measure salts and assess immune or infection-related markers when appropriate. Imaging such as kidney ultrasound may be used to check kidney size, structure and obstruction. In some patients, a kidney biopsy is recommended. During a biopsy, a small sample of kidney tissue is examined under a microscope to identify the exact pattern of disease and choose the most appropriate treatment.

Treatment Options

Glomerulonephritis treatment depends on the type of disease, the level of kidney function, the amount of protein in the urine, blood pressure, symptoms and biopsy findings if a biopsy is performed. The right approach is decided by a nephrologist or kidney specialist after a full assessment. Treatment is individualized, and patients should not start or stop medicines without medical advice.

General treatment often focuses on protecting the kidneys. This may include careful blood pressure control, reducing protein loss in the urine, managing swelling with fluid and salt guidance, and treating high cholesterol or anemia if present. Nutrition advice may involve adjusting salt, fluid or protein intake depending on kidney function and the patient’s overall condition.

When inflammation is active or caused by an immune process, doctors may consider medicines that reduce immune activity or control inflammation. If an infection is contributing, treatment may target the infection. In rapidly progressive or severe disease, hospital care may be needed for close monitoring, intravenous treatments or management of complications.

If glomerulonephritis leads to advanced kidney failure, kidney replacement therapies such as dialysis may be required. Kidney transplantation may be considered for suitable patients with end-stage kidney disease, depending on the cause and overall health. Supportive care, follow-up blood and urine tests, and long-term blood pressure management remain important at every stage.

Living With / Prognosis

Living with glomerulonephritis usually involves regular follow-up with a kidney specialist. Monitoring helps detect changes in kidney function, blood pressure, urine protein and fluid balance. Some forms resolve completely, especially certain post-infectious types, while others may recur or progress slowly over time.

Patients can support kidney health by attending appointments, taking prescribed medicines as directed, avoiding unnecessary kidney-stressing medicines unless approved by a doctor and keeping blood pressure well managed. A balanced diet, reducing excess salt, not smoking and maintaining a healthy weight may also help reduce strain on the kidneys and cardiovascular system.

The prognosis is highly individual. Factors that influence outcome include the exact type of glomerulonephritis, the degree of scarring on biopsy, response to treatment, blood pressure control and the amount of protein in the urine. With early diagnosis and consistent care, many people maintain stable kidney function for long periods.

For international patients who need evaluation or ongoing care, Acibadem International provides access to multidisciplinary nephrology teams and JCI-accredited hospitals for diagnosis and treatment of kidney diseases, including glomerulonephritis.

When to See a Doctor

A person should seek medical advice if they notice blood-colored urine, persistent foamy urine, swelling around the eyes or ankles, unexplained high blood pressure, reduced urination or unusual tiredness. These symptoms do not always mean glomerulonephritis, but they should be checked because they may indicate kidney or urinary tract problems.

Prompt medical care is especially important if symptoms appear after a recent throat infection, skin infection or illness, or if there is known autoimmune disease. People with existing kidney disease should contact their doctor if swelling increases, blood pressure rises, urine output falls or blood tests become abnormal.

Emergency assessment may be needed for severe shortness of breath, very little urine, confusion, chest discomfort or severe swelling, as these can suggest significant fluid overload or reduced kidney function. Early evaluation allows doctors to identify the cause, prevent complications and start appropriate treatment when needed.

Frequently asked questions

What is glomerulonephritis?

Glomerulonephritis is inflammation of the glomeruli, the tiny filters in the kidneys that clean the blood. When these filters are inflamed, blood or protein may leak into the urine and kidney function may decrease. It can be sudden or long-term, depending on the cause.

What are the first signs of glomerulonephritis?

Early signs may include dark, red or tea-colored urine, foamy urine, swelling of the face or ankles, and high blood pressure. Some people have no symptoms and are diagnosed after routine urine or blood tests. Any persistent urine change should be discussed with a doctor.

Is glomerulonephritis the same as a kidney infection?

No. A kidney infection is usually caused by bacteria in the urinary tract, while glomerulonephritis is inflammation of the kidney filters, often related to immune system activity. Infections can sometimes trigger glomerulonephritis, but the diagnosis and treatment are different.

Can glomerulonephritis be cured?

Some types of glomerulonephritis improve or resolve, especially when they are related to a temporary trigger such as certain infections. Other forms are chronic and require long-term monitoring and treatment to protect kidney function. The chance of recovery depends on the cause, severity and response to treatment.

How is glomerulonephritis diagnosed?

Doctors usually use urine tests to check for blood and protein, blood tests to measure kidney function, and blood pressure assessment. Additional immune or infection tests may be needed. In some cases, a kidney biopsy is performed to identify the exact type of disease.

What happens if glomerulonephritis is not treated?

Untreated active glomerulonephritis can lead to worsening high blood pressure, increasing protein loss in the urine and reduced kidney function. Some forms may progress to chronic kidney disease. Early diagnosis and follow-up improve the chance of preserving kidney health.

Which specialist treats glomerulonephritis?

Glomerulonephritis is usually treated by a nephrologist, a doctor who specializes in kidney diseases. Depending on the cause, care may also involve rheumatology, infectious disease, cardiology, nutrition or transplant specialists. A coordinated approach helps tailor treatment to the patient’s condition.

References

• National Institute of Diabetes and Digestive and Kidney Diseases
• National Kidney Foundation
• Kidney Disease: Improving Global Outcomes
• Mayo Clinic
• American Society of Nephrology

This article is for general information only and is not a substitute for professional medical advice. Please consult a qualified doctor about your individual situation.