Minimal change disease

Definition

Minimal change disease is a kidney disorder that can lead to nephrotic syndrome. Nephrotic syndrome is a group of symptoms that include protein in the urine, low blood protein levels in the blood, high cholesterol levels, high triglyceride levels, and swelling.

Alternative Names

Minimal change nephrotic syndrome; Nil disease; Lipoid nephrosis; Idiopathic nephrotic syndrome of childhood

Causes

Each kidney is made of more than a million units called nephrons, which filter blood and produce urine.

In minimal change disease, there is damage to the glomeruli. These are the tiny blood vessels inside the nephron where blood is filtered to make urine and waste is removed. The disease gets its name because this damage is not visible under a regular microscope. It can only be seen under a very powerful microscope called an electron microscope.

Minimal change disease is the most common cause of nephrotic syndrome in children. It is also seen in adults with nephrotic syndrome, but is less common.

The cause is unknown, but the disease may occur after or be related to:

Allergic reactions
Use of non-steroidal anti-inflammatory drugs (NSAIDs)
Tumors
Vaccinations (flu and pneumococcal, though rare)
Viral infections

Symptoms

There may be symptoms of nephrotic syndrome, including:

Foamy appearance of the urine
Poor appetite
Swelling (especially around the eyes, feet and ankles, and in the abdomen)
Weight gain (from fluid retention)

Minimal change disease does not reduce the amount of urine produced. It rarely progresses to kidney failure.

Exams and Tests

The health care provider may not be able to see any signs of the disease, other than swelling. Blood and urine tests reveal signs of nephrotic syndrome, including:

High level of cholesterol in the blood
High levels of protein in the urine
Low levels of albumin in the blood

A kidney biopsy and examination of the tissue with an electron microscope can show signs of minimal change disease.

Treatment

Medicines called corticosteroids (or steroids) can cure minimal change disease in most children. Some children may need to stay on steroids to keep the disease from returning.

Steroids are effective in adults, but less so in children. Adults may have more frequent relapses and become dependent on steroids.

If steroids are not effective, the provider will likely suggest other medicines.

Swelling may be treated with:

ACE inhibitor medicines
Blood pressure control
Diuretics (water pills)

You may also be told to reduce the amount of salt in your diet.

Outlook (Prognosis)

Children usually respond better to corticosteroids than adults. Children often respond within the first month of treatment.

A relapse can occur. The condition may improve after long-term treatment with corticosteroids and medicines that suppress the immune system (immunosuppressants).

When to Contact a Medical Professional

Contact your provider if:

You develop symptoms of minimal change disease
You have this disorder and your symptoms get worse
You develop new symptoms, including side effects from the medicines used to treat the disorder

References

Erkan E. Nephrotic syndrome. In: Kliegman RM, St. Geme JW, Blum NJ, et al, eds. Nelson Textbook of Pediatrics. 22nd ed. Philadelphia, PA: Elsevier; 2025:chap 567.

Radhakrishnan J, Appel GB, D'Agati VD. Secondary glomerular disease. In: Yu ASL, Chertow GM, Luyckx VA, Marsden PA, Skorecki K, Taal MW, eds. Brenner and Rector's The Kidney. 11th ed. Philadelphia, PA: Elsevier; 2020:chap 32.