This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
CANCA Positivity is specific for: 
Select and explain. 
A. Polyaeritis Nodosa, B. Wegener's granulomatosis, C. Henoch shontein purpura, D. Churg strouss syndrome
B: Wegener's granulomatosis
Answer: B: Wegener's granulomatosis 
Explanation: Answer is B (Wegener's granulomatosis): CANCA refers to Cytoplasmic Antineutrophilic cytoplasmic antibodies and its presence is highly specific for Wegener's granulomatosis