This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Medicine
Feature of microscopic polyangitis is: 
Select and explain. 
A. IgG deposits in kidney, B. Bronchospasm, C. Renal involvement in 80% of cases, D. All of the above
C: Renal involvement in 80% of cases
Answer: C: Renal involvement in 80% of cases 
Explanation: Renal involvement is seen in at least 80% ofpatients with MPA. Renal involvement is seen in at least 80% of patients with MPA Renal involvement is seen in at least 80% of patients with MPA - CRDT Glomerulonephritis occurs in atleast 79% of patients - Harrison Microscopic polyangitis is not associated with IgG Deposits in kidney Microscopic Polyangitis is a pauci-immune glomerulonephritis. Immunofluorescence and electron microscopy show no immune deposits Microscopic Polyangitis is not associated with bronchospasm Asthma (bronchospasm) and Eosinophilia are features of Churg-Strauss Syndrome and are typically absent in microscopic polyangitis. REF: Harrison book of internal medicine 21ST EDITION