What is Microscopic Polyangiitis?

Microscopic polyangiitis is a rare type of autoimmune disease. Problems occur when the immune system triggers inflammation in small blood vessels throughout the body, which leads to poor blood circulation and ruptures. The disease can affect the joints, skin, kidneys, lungs, and other vital organs, sometimes creating life-threatening complications. People who have microscopic polyangiitis generally need to undergo several rounds of immunosuppressive therapy to relieve symptoms and prevent future organ damage.

The exact causes of microscopic polyangiitis are not known. The immune system begins to attack healthy blood cells and blood vessel tissues as if they were dangerous pathogens. The resulting inflammation and swelling causes blood vessels to become weakened, stretched thin, and very fragile. Organs are unable to receive a steady supply of fresh blood and nutrients from damaged vessels, which can lead to a number of health problems. Microscopic polyangiitis can affect people of any age, but it is most prevalent in patients over the age of 50.

Symptoms of microscopic polyangiitis can vary depending on which parts of the body are affected and to what degree. Most people with the disease experience generalized symptoms of weakness, muscle fatigue, loss of appetite, and frequent fevers. It is also possible to experience debilitating joint pains and widespread skin rashes. If the lungs are involved, a person may have shortness of breath, extreme fatigue during physical activity, and a persistent wet or bloody cough. Other serious complications can arise if the blood vessels that feed the kidneys are severely damaged.

A series of diagnostic tests are needed to confirm microscopic polyangiitis and rule out other potential causes of symptoms. Doctors screen blood and urine samples to check for abnormal levels of specific types of white blood cells, proteins, and antibodies. X-rays and computerized tomography scans are used to determine the extent of joint and organ damage. A blood vessel biopsy may be considered as well to confirm the presence of inflammation.

Most people who have microscopic polyangiitis are given corticosteroids, such as prednisone, to combat blood vessel inflammation. They are also started on a course of immunosuppressive drugs that slow down or block immune system activity. Depending on the severity and nature of symptoms, a patient may need to receive therapy for a year or longer. The disease can cause recurring health issues even after a successful round of treatment, so patients are encouraged to meet with their doctors regularly for the rest of their lives in hopes of identifying new problems as early as possible.