Minimal change disease

• Alternative Names

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

• Causes, incidence, and risk factors

  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 -- the tiny blood vessels inside the nephron. The disease gets its name because this damage isn't visible under a regular microscope. It can only be seen under an electron microscope.

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

  The cause is unknown, but the disease may occur after:

  • Allergic reactions
  • Recent immunizations
  • Viral infection
• Symptoms

  There may be symptoms of nephrotic syndrome:

  • 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.

• Signs and tests

  The doctor may not be able to see any obvious outward signs of the disease, other than swelling. Blood and urine tests reveal signs typical of nephrotic syndrome, including:

  • High cholesterol
  • 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. An immunofluorescence exam of the biopsied kidney tissue is negative.

• Treatment

  Corticosteroids can cure minimal change disease in most children. Some patients may need to stay on steroids to keep the disease in remission.

  Adults do not respond to steroids quite as well as children, but many still do find steroids effective. Adults may have more frequent relapses and steroid dependence.

  Patients who have three or more relapses may do better with cytotoxic therapy. In most cases, this involves a medication called cyclophosphamide. Other medicines that have been used include cyclosporine and chlorambucil.

  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.

• Expectations (prognosis)

  Minimal change disease usually responds well to corticosteroids, often within the first month. A relapse can occur, but patients may improve after prolonged treatment with corticosteroids and medications that suppress the immune system (immunosuppressive medications).

• Complications
  • Nephrotic syndrome
  • Side effects of medications
• Calling your health care provider

  Call for an appointment with your health care provider if you develop symptoms of minimal change disease.

  If you have this disorder, call for an appointment with your health care provider if your symptoms worsen or you develop new symptoms, including side effects from the medications used to treat the disorder.

• Prevention

  There is no known prevention.

• References

  Appel GB. Glomerular disorders and nephrotic syndromes. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007: chap 122.

Review Date: 11/30/2009

Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; Herbert Y. Lin, MD, PHD, Nephrologist, Massachusetts General Hospital; Associate Professor of Medicine, Harvard Medical School. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.