Short summary

Glomerulonephritis is a group of kidney diseases characterized by inflammation or damage in the glomeruli, the filtering units of the kidneys. It may appear with blood in the urine, foamy urine, swelling, and high blood pressure; in some cases it follows a silent course and is noticed only through laboratory tests. ^[1][2]

What is glomerulonephritis?

The glomeruli are tiny filter structures that help the kidneys remove waste and excess fluid from the blood. Glomerulonephritis means inflammation or damage in these structures. NIDDK and MedlinePlus note that when the filtration barrier is disrupted, protein and red blood cells can leak into the urine, leading to swelling and impaired kidney function. The disease is not linked to a single cause; it may be acute or chronic, may occur on its own, or may be part of another illness such as lupus. For that reason, the term “kidney inflammation” covers a broad clinical picture. ^[1][2][3]

What are the symptoms?

Glomerulonephritis may cause dark, reddish, or cola-colored urine; foamy urine; swelling of the face, feet, or legs; high blood pressure; fatigue; and sometimes decreased urine output. However, some people have no symptoms at all, and the diagnosis comes up after protein or blood is found on a routine urine test. Having no complaints does not mean the kidneys are unaffected. Kidney evaluation is especially important when swelling and high blood pressure are present together. In advanced cases, shortness of breath or uremic symptoms may appear. ^[1][2][4]

What causes it?

The causes are quite varied. In some cases, recently passed infections—especially post-streptococcal immune responses—may play a role. In others, IgA nephropathy, lupus, vasculitis, anti-GBM disease, or other immune-system disorders may be the main issue. Glomerulonephritis can sometimes be primary, meaning limited to the kidney, and sometimes secondary, meaning part of a systemic disease. This distinction is critical for treatment planning. Not every case of blood in the urine means glomerulonephritis; stones, infection, tumors, or structural causes may also need to be investigated. ^[1][2][3]

How is it diagnosed?

The diagnostic process includes urinalysis, measurement of protein in the urine, blood tests, kidney function tests, immune-related tests, and imaging. In the medical history, the doctor asks about recent infection, rash, joint pain, medication use, and family history. In some patients, a kidney biopsy is necessary to understand the exact subtype. A biopsy helps guide treatment by showing the type of disease, its activity, and the degree of damage. For that reason, even though the decision may sound intimidating, biopsy is often important for choosing the right treatment. ^[1][2][3]

How is treatment planned?

Treatment varies according to the underlying cause. Fluid and salt control, blood pressure regulation, and kidney-protective medications form the foundation in many patients. In some cases, immunosuppressive drugs, corticosteroids, or plasmapheresis may be needed. In infection-related cases, priority is given to treating the cause. If advanced kidney failure develops, dialysis may become necessary temporarily or permanently. The goal of treatment is not only to improve laboratory values, but also to slow the loss of kidney function and prevent complications. ^[1][2][4]

What should be monitored at home?

Blood pressure, increasing swelling, urine output, and changes in body weight are important. Frequent use of NSAID painkillers without a doctor’s advice may be harmful for some kidney patients. Salt restriction, fluid planning, and protein intake should be tailored individually; there is no single diet that fits everyone. Herbal products or detox practices marketed as “cleansing the kidneys” may not be safe. In kidney disease, individualized medical evaluation is essential. ^[1][3][4]

Which situations are emergencies?

A marked decrease in urine output, shortness of breath, rapidly increasing swelling, very high blood pressure, chest pain, confusion, or blood in the urine together with deterioration in general condition requires urgent evaluation. These findings may be related to rapid worsening of kidney function or fluid overload. In addition, in people with known glomerulonephritis, infection, medication side effects, or sudden blood-pressure spikes may also require prompt intervention. Even more subtle complaints such as persistent fatigue and loss of appetite can signal that it is time for reassessment. ^[1][2][4]

Long-term outlook

The course of glomerulonephritis varies greatly depending on the underlying cause. Some acute cases improve, while others may progress to chronic kidney disease. Early diagnosis, blood pressure control, and regular nephrology follow-up affect long-term outcomes. After diagnosis, it is better to track urine protein levels, creatinine, blood pressure, and clinical symptoms together rather than focusing on a single lab result. Regular follow-up reduces the risk of silent progression and offers a chance to intensify treatment on time when needed. ^[1][2][3]

Personal medical evaluation is important when symptoms are prolonged, worsening, or unusual; this content does not replace diagnosis. ^[1][2]

FAQ

Is glomerulonephritis the same as a kidney infection?

No. Glomerulonephritis is inflammatory damage to the kidney’s filtering structures; it is different from a typical urinary tract or kidney infection. ^[1][2]

Why does urine become foamy in glomerulonephritis?

When protein leaks into the urine, it may create a foamy appearance. This can be a sign of proteinuria and should be evaluated. ^[1][3]

Does every patient need a kidney biopsy?

No. However, in some patients it can be very important for clarifying the disease type and treatment. ^[1][2]

Can glomerulonephritis be completely cured?

The course depends on the cause. Some acute cases may improve, while in others chronic kidney disease may develop. ^[1][2][3]

Which symptoms are emergencies?

Reduced urine output, shortness of breath, rapidly increasing swelling, very high blood pressure, and deterioration in overall condition require urgent evaluation. ^[1][2]