Microscopic polyangiitis (MPA)

Microscopic polyangiitis (MPA) is a rare form of ANCA-associated vasculitis in which the immune system attacks small blood vessels, leading to inflammation and damage in organs throughout the body. MPA most commonly affects the kidneys and lungs but can also involve the skin, nerves, joints, eyes, and other organ systems. Many people with MPA have anti-neutrophil cytoplasmic antibodies (ANCA), particularly MPO-ANCA, which target components within certain white blood cells.

Shortness of breath, coughing up blood, malaise, fatigue, fever, loss of appetite, weight loss, rashes, muscle and joint pain, abnormal sensations due to nerve damage, numbness, loss of strength, leg swelling, dark-colored urine, tiredness, weakness, sinus issues, and ear and eye problems.

Kidney diseases, glomerulonephritis, palpable purpura, uveitis, and rheumatoid arthritis.

MPA most commonly affects people in their 50s and 60s. While specific genes and immune system dysfunction are suspected of being involved, there is no known specific cause.

• Genetics of ANCA-associated vasculitis: role in pathogenesis, classification and management (2022)
• Systematic literature review informing the 2022 update of the EULAR recommendations for the management of ANCA-associated vasculitis (AAV): part 1– treatment of granulomatosis with polyangiitis and microscopic polyangiitis (2021)
• Treatment of granulomatosis with polyangiitis and microscopic polyangiitis (2020)
• An update on the epidemiology of ANCA-associated vasculitis (2020)