A 48-year-old man has a large central septal perforation with crusting, a saddle nose deformity, recurrent epistaxis, and recent onset haemoptysis. Which single investigation is MOST likely to establish the underlying diagnosis?

• A Urine drug screen for cocaine metabolites
• B Serum ACE level
• C VDRL test
• D Serum c-ANCA (anti-proteinase 3 antibody) ✓

Explanation

Granulomatosis with polyangiitis classically produces a combination of nasal septal destruction, saddle nose deformity, and pulmonary involvement such as haemoptysis. PR3-ANCA (c-ANCA) is positive in about 90 percent of active systemic cases and confirms the diagnosis. Syphilis causes perforation without haemoptysis, sarcoidosis is associated with elevated serum ACE but typically with lupus pernio and hilar nodes, and cocaine causes perforation with a negative ANCA profile unless there is levamisole-associated vasculitis.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.