Description
Why It’s Done
The C-ANCA test is mainly used to help diagnose and monitor autoimmune vasculitis, particularly:
• Granulomatosis with polyangiitis (GPA) – formerly known as Wegener’s granulomatosis
• Microscopic polyangiitis (MPA) (less commonly shows C-ANCA, more often P-ANCA)
• Other autoimmune or inflammatory diseases involving blood vessels
Doctors may recommend this test if a patient shows signs such as:
• Persistent sinus or respiratory infections
• Lung nodules or infiltrates
• Kidney problems (hematuria, proteinuria)
• Unexplained fever, fatigue, or weight loss
• Skin rashes or joint pain
Preparation for the Test
• Fasting: Not required.
• Medications: Inform your healthcare provider about any current medications, as some drugs can affect the immune system and influence test results.
• No special preparation is needed before the test.
