Your doctor may suspect Granulomatosis with polyangiitis (Wegener's) if you have:
Unusually persistent symptoms of sinusitis
Respiratory tract symptoms or
Unexplained kidney disease
And your symptoms have worsened despite treatment.
Many early symptoms of Granulomatosis with polyangiitis (Wegener's) are similar to those of milder and more common respiratory problems. As a result, the average person with Granulomatosis with polyangiitis (Wegener's) often has symptoms for months before the correct diagnosis is made.
Your doctor will review your symptoms and medical history. This will include any treatments that you have received so far.
Your doctor will conduct a thorough physical examination. He or she will carefully check your entire respiratory tract, from the tip of your nose to the base of your lungs. The doctor will look for evidence of inflammation and tissue injury. Your doctor may also examine your eyes, ears, heart and skin.
After the physical exam, your doctor may send you for tests. These tests will look for inflammation and organ damage. The tests will focus on your upper respiratory tract, lungs and kidneys. These tests may include:
Complete blood count (CBC) to look for:
Evidence of anemia (common in Granulomatosis with polyangiitis (Wegener's))
Abnormal white blood cell count
Platelet count abnormalities that might suggest another diagnosis
Blood tests that measure body-wide inflammation
Tests to measure kidney function
A blood test for an antibody that is found in most people with Granulomatosis with polyangiitis (Wegener's)called anti-neutrophilic cytoplasmic antibody (ANCA)
Urinalysis to check for kidney damage
Chest X-ray to look for evidence of lung damage or nodules
Sinus X-ray or computed tomography (CT) scan to determine whether you have sinusitis.
These tests also help to check for other illnesses that may cause symptoms similar to Granulomatosis with polyangiitis (Wegener's).
The only way to confirm this diagnosis is to have a biopsy. Tissue is taken from an affected organ. It is then examined under a microscope to check for granulomas and areas of inflammation.