Microscopic Polyangiitis: Causes, Symptoms, and Treatment
Medically reviewed by Harsha Moole, MD, Internal Medicine. Last reviewed: October 23, 2026.
What kind of doctor treats Microscopic Polyangiitis?
A rheumatologist, a doctor who treats autoimmune and joint diseases, usually treats microscopic polyangiitis (MPA). People with vasculitis in general may also need care from other doctors at times, such as a nephrologist (kidney doctor) or pulmonologist (lung doctor). A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.
What is microscopic polyangiitis?
Microscopic polyangiitis, or MPA, is a disorder that swells the blood vessels. This swelling is called vasculitis. It can lead to organ damage.
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 sexes.
Vasculitis is a group of rare diseases that cause swelling of the blood vessels.
Symptoms
MPA is one type of vasculitis. Vasculitis in general can cause poor blood flow to organs like the lungs, kidneys, skin, eyes, or nerves. Symptoms of vasculitis include:
- Rashes, such as red spots, lumps, or sores.
- Headaches with vision changes.
- Shortness of breath and cough.
- Numbness or weakness in a hand or foot.
- Joint pain, fatigue, or sinus problems in some people.
Vasculitis may seriously affect the kidneys without many symptoms at first. Patients with vasculitis may have one or repeated episodes throughout their life.
Causes and who gets it
The cause of MPA is unknown. Some types of vasculitis are reactions to medications, cancer, or viral infections like hepatitis B or C.
How doctors diagnose it
A rheumatologist can make the diagnosis. Doctors use symptoms, a physical exam, and lab tests. They may also use a tissue biopsy, which is a small tissue sample checked in a lab, and sometimes imaging.
Treatment
The goal of vasculitis treatment is usually to slow down the body's attack on the blood vessels. In vasculitis, doctors focus on preventing lasting damage to organs like the lungs, kidneys, brain, or nerves.
- Steroid medicines are used to treat swelling in many types of vasculitis. Steroids can thin the bones and the skin. They can also raise blood sugar and blood pressure.
- For milder vasculitis, doctors may use medicines that weaken the immune system. Possible side effects include a higher risk of infection and birth defects.
- Newer drugs such as rituximab or avacopan can treat MPA.
- Cyclophosphamide, a strong medicine, is used for disease that is life-threatening.
- Some people with severe disease have plasma exchange. In plasma exchange, the liquid part of the blood is removed and replaced with donor plasma or saline.
If severe vasculitis damages blood vessels or organs, surgery may be needed to repair them. With treatment, vasculitis can go into remission, a time when you do not have symptoms.
People who take medicines that weaken the immune system need to lower their risk of infection. Side effects from medicines like glucocorticoids may need close checks by a rheumatologist.
When to see a doctor
Talk to a doctor about symptoms such as rashes, shortness of breath, cough, or numbness or weakness in a hand or foot. Vasculitis can harm the kidneys without many early symptoms.
Call 911 or go to the emergency room for coughing up blood, severe trouble breathing, chest pain that does not go away, or fainting.
How a direct primary care or concierge doctor fits in
A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. A direct primary care doctor can look at your symptoms, order basic blood and urine tests, and refer you to a rheumatologist. They can also help keep track of your care between specialist visits.
Common questions
What parts of the body does microscopic polyangiitis affect?
It most often affects the kidneys, lungs, nerves, skin, and joints.
Can doctors treat microscopic polyangiitis?
Yes. Treatment aims to slow the body's attack on the blood vessels. With treatment, vasculitis can go into remission, a time when you do not have symptoms.
What kind of doctor diagnoses microscopic polyangiitis?
A rheumatologist can make the diagnosis. Doctors use symptoms, an exam, lab tests, a tissue biopsy, and sometimes imaging.
Can microscopic polyangiitis harm the kidneys without warning signs?
Yes, it can. The kidneys are among the most commonly affected areas in MPA. Vasculitis in general may seriously affect the kidneys without many symptoms at first.
Is microscopic polyangiitis only found in older adults?
No. MPA is diagnosed in people of all ages, all ethnicities, and both sexes.
Sources
- NIH GARD - Microscopic polyangiitis
- American College of Rheumatology - Vasculitis
- NHLBI, NIH - Vasculitis Treatment
Medical Disclaimer
This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.
