Diagnosing GPA and MPA

Your doctor will diagnose you based on your signs and symptoms, your medical history, a physical exam, and test results. Unfortunately, there is no one simple test that can diagnose Granulomatosis with Polyangiitis (GPA) (formerly known as Wegener's Granulomatosis) and Microscopic Polyangiitis (MPA). Often, the path to diagnosis can be a long, confusing, and frustrating one.

A combination of tests are performed

In order to diagnose GPA and MPA, doctors may perform a combination of tests, including:

  • Blood tests: Blood tests can show if you have abnormal levels of certain blood cells and antibodies in your blood. A blood test will be performed to check for ANCAs
  • Biopsy: During a biopsy, your doctor will take a tissue sample from a blood vessel or an affected organ. A pathologist, a doctor who specializes in studying cells and tissues under a microscope, will look at the sample for signs of inflammation or tissue damage
  • Urine test: You will provide a urine sample for evaluation. This test looks for any abnormal levels of protein or blood cells in the urine, which can be signs that your kidneys are affected
  • Chest X-ray: This is a test that creates pictures of the structures inside your chest, such as your heart, lungs, and blood vessels. An abnormal chest X-ray may show any changes that may be affecting your lungs
  • Computed tomography scans: A computed tomography scan (usually called a CT scan) is a type of X-ray that creates more detailed pictures of your internal organs than a standard X-ray. It can show abnormalities that have developed in your sinuses, chest, or abdominal organs

Keep in mind

Only your doctor can diagnose you. Talk with him or her about any symptoms you may be having and what treatments may be right for you.


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