Microscopic polyangiitis (MPA) is a condition that causes small blood vessels to be inflamed. It’s a rare type of vasculitis. The disease can damage the blood vessels and cause problems in organs around the body. MPA most often affects people in their 50s and 60s, but it can happen in people of any age.
Blood vessels carry blood around the body. Arteries carry blood with oxygen from the heart around the body. Arterioles are small branches of arteries. Veins carry blood back to the heart. Venules are small branches of veins. The smallest blood vessels are called capillaries. These tiny blood vessels trade oxygen and nutrients for waste products.
Until recently, healthcare providers thought MPA was a form of a condition called polyarteritis nodosa. But MPA affects smaller vessels and causes different problems. Healthcare providers now treat it as a separate condition.
MPA often causes damage in the filtering part of the kidneys. This damage may cause blood and protein to be lost in the urine. This may also cause loss of kidney function. MPA can also affect the lungs, the skin, the eyes, and the nervous system.
Researchers are working to understand the causes of MPA. Certain genes may be a cause. Problems with the immune system may also be a cause. MPA sometimes happens along with an autoimmune disease, such as rheumatoid arthritis (RA). An autoimmune disease is caused by a problem with the immune system. The immune system’s job is to protect the body from disease. It does this by attacking things in the body, such as viruses, that may cause harm. When you have an autoimmune disease, your immune system attacks your own body.
Other possible causes may be infections caused by viruses. Reaction to certain medicines can also start an inflammation in the blood vessels.
MPA can cause problems throughout your body. The inflammation may come and go. The symptoms can get better or worse at times. Common symptoms of MPA include:
The kidneys are the organs most often affected. But you may not have kidney symptoms until the damage is serious. The kidney symptoms can suddenly get worse and then get better again. In some cases, kidney damage may cause no symptoms. But there is still loss of kidney function.
MPA can be hard to diagnose. The symptoms of MPA can be like those of many other conditions. But, it is important to receive a prompt diagnosis and treatment to help avoid permanent organ damage.
Your healthcare provider will ask about your medical history and your symptoms. He or she will give you a physical exam. Your healthcare provider may examine your skin for rashes and look for signs of nerve damage. He or she may need to take a sample (biopsy) from your skin or kidneys to look for damage.
You may have a blood test to look for antineutrophil cytoplasmic (ANCA) antibodies. This test can help confirm a diagnosis. But not everyone with MPA has ANCA antibodies. Also, not everyone with ANCA antibodies has the same condition.
You may also need tests such as:
The physical exam, blood test, biopsies, and other tests together can help your healthcare provider form a diagnosis.
Quick diagnosis and treatment can help control the condition. You may need to see several types of healthcare providers. For example, you may need to see a rheumatologist. This is a healthcare provider who treats joint diseases, autoimmune diseases, and vasculitis. You may see other healthcare providers to focus on kidney or lung problems.
The goal of treatment is to prevent permanent organ and nerve damage. Your treatment will likely start with steroids. These reduce inflammation. You take these medicines by mouth, or in some cases through a vein (IV). Steroids can cause side effects. Talk with your healthcare provider about the best way to deal with the side effects.
You may also need to take other medicines that suppress the immune system. These are called immunosuppressants. They also help control the inflammation. The first round of this therapy is needed to bring the disease under control. It’s called induction therapy. Once the active inflammation is gone, you may be able to take lower doses of medicines. This is called maintenance therapy. This can help to reduce the risk that the disease will flare up again.
Induction therapy often lasts for about 3 to 6 months. It may include:
Maintenance therapy often lasts for about 12 to 18 months, or longer. It may include:
If untreated, MPA can cause permanent damage to the organs.
The strong medicines needed to treat the condition can cause side effects. Steroids can increase the risk of bone loss, high blood pressure, mood changes, high blood sugar, muscle weakness, and skin problems. Immunosuppressant medicines can increase the risk of infections.
In addition, people with MPA may have bouts of fatigue, pain, and other problems related to their condition.
With treatment, most people with MPA have a good outcome. Your healthcare provider can help you manage the condition. He or she may give you advice about dealing with medicine side effects and avoiding infections.
You will likely need close follow-up to watch for possible relapse. It’s very important to stick with your medicine routine. This can help to prevent complications and organ damage. It is also important to keep up physical activity and good nutrition, even if you don’t feel your best. Your healthcare provider can help you with the best treatment plan for you. Work closely with your healthcare provider to have the best outcome.
Tips to help you get the most from a visit to your healthcare provider:
© 2019 Fremont Health
All Rights Reserved.
450 East 23rd Street Fremont, NE 68025