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Microscopic polyangiitis
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A member of my family has microscopic polyangiitis. What can you tell me about this condition?



  • What is microscopic polyangiitis (MPA)? (Back to Top)

  • 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 Reviewed: 2/4/2009

  • What are the symptoms of microscopic polyangiitis (MPA)? (Back to Top)

  • 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 Reviewed: 2/4/2009

  • What causes microscopic polyangiitis (MPA)? (Back to Top)

  • The cause of MPA is unknown. 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 Reviewed: 2/4/2009

  • What is the treatment for microscopic polyangiitis (MPA)? (Back to Top)

  • 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 Reviewed: 2/4/2009

  • What is the prognosis for inviduals with microscopic polyangiitis (MPA)? (Back to Top)

  • 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 Reviewed: 2/4/2009


References  (Back)
  1. What You Need to Know About Microscopic Polyangiitis . Cleveland Clinic Web site. October 27, 2006 Available at: http://www.clevelandclinic.org/arthritis/treat/facts/microscopic%20polyangiitis.htm. Accessed February 04, 2009.
  2. Microscopic polyangiitis. The Johns Hopkins Vasculitis Center Web site. Available at: http://vasculitis.med.jhu.edu/typesof/polyangiitis.html. Accessed February 04, 2009.
  3. Farid-Moayer M. Microscopic polyangiitis. eMedicine Journal Web site. December 6, 2006 Available at: http://www.emedicine.com/med/TOPIC2931.HTM. Accessed February 04, 2009.

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