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: Pathology
Granuloma is seen in all except - 
Select and explain. 
A. Giant cell aeritis, B. Microscopic polyangitis, C. Wegner's granulomatosis, D. Churg-strauss disease
B: Microscopic polyangitis
Answer: B: Microscopic polyangitis 
Explanation: Ans. is 'b' i.e., Microscopic polyangitisIn microscopic polyangitis, granuloma are absent.o There are two types of inflammation in the wall of vessels in systemic vasculitis ?I. Granulomatous inflammation --> characterized by formation of granuloma in vessel wall.2. Necrotizing inflammation characterized by fibrinoid necrosis in the vessel wall.Vasculitis with granulomatous inflammation o Giant cell aeritiso Takayasu's diseaseo Wegner's granulomatosiso Churg strauss syndromeVasculitis with necrotizing inflammationPolyaeritis nodosaChurg strauss syndromeWegner's granulomatosisMicroscopic polyangitisNote - Wegner's granulomatosis and churg strauss syndrome have feature of both granulomatous inflammation (predominant) and necrotizing inflammation.