bone, joint, and muscle disorders
Granulomatosis with Polyangiitis
Diagnosis of Granulomatosis with Polyangiitis
A doctor's evaluation Imaging tests Blood and urine tests Biopsy Granulomatosis with polyangiitis must be diagnosed and treated early to prevent complications, including kidney disorders, lung disorders, and heart attacks. Doctors usually suspect the diagnosis of granulomatosis with polyangiitis based on the distinctive pattern of symptoms. For example, doctors suspect the diagnosis when people have unexplained respiratory symptoms (including otitis media in adults, which is otherwise unusual) particularly if problems in other organs, especially the kidneys, exist. Doctors also suspect the diagnosis in people who have a long history of sinus problems that have not been cured by or only partially cured by antibiotics. A chest x-ray is done because the lungs are usually affected. However, symptoms and chest x-rays can resemble those of several lung disorders, making the diagnosis difficult. So doctors also do a computed tomography (CT) scan of the chest to look for things the chest x-ray might miss, such as cavities or areas of inflammation in the lungs that may mimic cancer or infection. Although blood test results cannot specifically identify granulomatosis with polyangiitis, they can strongly support the diagnosis. One such test can detect antineutrophil cytoplasmic antibodies (c-ANCA) in the blood. These antibodies occur in several types of vasculitis and trigger certain white blood cells to attack normal organs. Other specific antibodies are identified with further testing. People with this disorder may have blood and protein in their urine due to kidney inflammation. Because kidney inflammation can cause damage without causing symptoms, doctors always do a urine test to detect this inflammation. Doctors can confirm the diagnosis by examining a small piece of tissue under a microscope (biopsy). The tissue sample may be taken from an affected area, such as the airways or lungs. Skin and kidney biopsies may occasionally be helpful. Sometimes, the tissue sample is taken from the nasal passages, but biopsy of nasal tissue only rarely provides a definite diagnosis. 