How is eosinophilic granulomatosis with polyangiitis (EGPA) diagnosed?
The doctor may use the following tests to diagnose EGPA:
- Medical history: to look for EGPA symptoms, especially asthma, allergies, and other features of the disease.
- Physical examination: to discover which organs are involved and to rule out other illnesses that may look similar.
- Blood tests: to look for abnormal blood counts and an increase in eosinophils.
- Urinalysis: to detect whether there is too much protein, or red blood cells, in the urine.
- Imaging tests such as x-rays and computed tomography (CT) to look for any abnormalities in areas such as the lungs or sinuses.
Once the diagnosis of EGPA is suspected, a biopsy (tissue sample) is often performed to try to find eosinophils, eosinophilic granulomas, and/or vasculitis. Biopsies are not required in all cases, and are only recommended when abnormal findings are seen in the exam, laboratory tests, or imaging tests.