Your browser does not support javascript:   Search for gard hereSearch for news-and-events here.


Genetic and Rare Diseases Information Center (GARD)

Microscopic polyangiitis

Related Diseases
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.

Your Question

My 12-year-old son was recently diagnosed with microscopic polyangiitis, presenting with acute renal failure. I need information regarding cause, treatment, and prognosis. I am specifically interested in information on pediatric cases of this disorder.

Our Answer

We have identified the following information that we hope you find helpful. If you still have questions, please contact us.

What is microscopic polyangiitis (MPA)?

Microscopic polyangiitis (MPA) is a disorder that causes blood vessel inflammation (vasculitis), which can lead to organ damage.[1] The kidneys, lungs, nerves, skin, and joints are the most commonly affected areas of the body. MPA is diagnosed in people of all ages, all ethnicities, and both genders.[2] The cause of this disorder is unknown.
Last updated: 8/13/2014

What are the symptoms of microscopic polyangiitis (MPA)?

The symptoms of MPA depend on which blood vessels are involved and what organs in the body are affected. The most common symptoms of MPA include kidney inflammation, weight loss, skin lesions, nerve damage, and fevers.[2] This disorder may occur alone or with other disorders, such as temporal arteritis.
Last updated: 2/4/2009

What causes microscopic polyangiitis (MPA)?

The cause of MPA is unknown. It is not contagious, does not usually run in families, and is not a form of cancer. The immune system is thought to play a critical role in the development of MPA.  It is thought that the immune system becomes overactive and causes blood vessel and tissue inflammation, which leads to organ damage. It is not known what causes the immune system to become overactive.[1]
Last updated: 8/13/2014

What is the treatment for microscopic polyangiitis (MPA)?

MPA is treated with medications that suppress the immune system, which can lower an individual's resistance to infections. There are a variety of immune suppressing medications that are used in MPA; however, resources state that a steroid (usually prednisone) and a medication toxic to cells (usually starting with cyclophosphamide) are typically prescribed first.[2] The goal of treatment is to stop all of the organ damage that occurs as a result of MPA.[1]  The duration of treatment with immune suppressing medication varies between individuals, but is typically given for at least one to two years.[1]
Last updated: 2/4/2009

What is the prognosis for inviduals with microscopic polyangiitis (MPA)?

The prognosis for MPA depends on the severity of the condition. The best prognosis is made when treatment has been promptly initiated and is carefully monitored by a physician who is knowledgeable about MPA.[1] With treatment, 75 percent of individuals achieve complete remission.[3] After achieving remission, it is possible for MPA to recur (often referred to as a “relapse”). Relapses occur in about 50% of people with MPA. Achieving remission is again possible for most people with MPA.[1] One of the most significant complications among people who are treated with cyclophosphamide is bladder cancer. Approximately 16 percent of individuals develop bladder cancer within 15 years.[3]
Last updated: 2/4/2009

Do children diagnosed with microscopic polyangiitis (MPA) receive different treatment or have a different prognosis than adults?

Limited information is available on pediatric vasculitis and how it differs from vasculitis in adults. Most decisions regarding the treatment of children with MPA are made by using data obtained from research on adults.[4] The Childhood Arthritis Rheumatology Research Alliance conducted research on the feasibility of establishing a registry of children with chronic systemic vasculitis for participation in future research.[5] The abstract for this article is available through PubMed. You may wish to contact this organization to learn more about pediatric vasculitis research.

Childhood Arthritis Rheumatology Research Alliance
Dept. of Pediatrics, Div. of Rheumatology
300 Pasteur Drive
Boswell Building A081
Stanford, CA 94305-5208
Phone: 650-736-4364
Fax: 650-736-4344
Online email:
Web site:
Last updated: 7/22/2013

Related Diseases
See Disclaimer regarding information on this site. Some links on this page may take you to organizations outside of the National Institutes of Health.