Microscopic Polyangiitis

Microscopic polyangiitis (MPA) is an inflammatory vascular condition that affects many organ systems, especially the kidneys.

About Microscopic Polyangiitis

Microscopic polyangiitis is a form of vasculitis (inflammatory vascular disease) that affects small vessels, disrupting blood flow to tissues throughout your body. The primary organ system affected in MPA is the kidneys. Other organs that may be affected include your nervous system, eyes, skin, and lungs.

Along with granulomatosis with polyangiitis (GPA) and eosinophilic granulomatosis with polyangiitis (EGPA), MPA is an anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis. In these diseases, vascular inflammation is caused by antibodies called ANCAs.

Symptoms of Microscopic Polyangiitis

Symptoms of microscopic polyangiitis vary based on the organ systems affected by the disease. They may also change over time.

Symptoms of microscopic polyangiitis may include:

  • Dark colored urine
  • Ear infections
  • Eye infections
  • Leg swelling
  • Sinus infections
  • Skin discoloration
  • Tingling and numbness
  • Tiredness, aches, or weakness in joints or muscles

Risk Factors for Microscopic Polyangiitis

Microscopic polyangiitis is more common in certain patient populations.

Risk factors for microscopic polyangiitis may include:

  • Age: MPA is prevalent in people between the ages of 50 and 70.
  • Comorbid conditions: MPA often occurs in conjunction with autoimmune diseases such as rheumatoid arthritis.

Treating Microscopic Polyangiitis at UT Medicine

Like all forms of vasculitis, corticosteroids like prednisone can be used to address the inflammation associated with microscopic polyangiitis. Your physician may prescribe an immunosuppressant medication such as rituximab, methotrexate, azathioprine, or mycophenolate mofetil.

Two women are jogging together along a tree-lined path in a park. They are dressed in athletic wear, one in a gray top and the other in a blue jacket with green accents. The background features blurred trees and other people, suggesting a lively, active environment.

UT Medicine Rheumatology Clinic

A person is seated at a desk, holding an orange mug in one hand. The background features beige curtains and a modern desk lamp, suggesting a cozy home office or study environment. The individual is wearing a blue sweater vest over a light shirt, and the scene is softly lit with natural daylight.

UT Medicine Vasculitis Clinic