A 70-year-old woman has a temporal headache, jaw claudication, and visual disturbance. ESR is 110 mm/hr. Temporal artery biopsy shows transmural granulomatous inflammation with giant cells at the intima-media junction and fragmentation of the internal elastic lamina. This condition predominantly affects which calibre of vessels?
- A Small vessels (capillaries, venules, arterioles)
- B Medium-sized muscular arteries only
- C Large and medium vessels (aorta and its major branches) ✓
- D Venous system exclusively
Correct answer: C. Large and medium vessels (aorta and its major branches)
Explanation
Giant cell (temporal) arteritis (GCA) is the most common vasculitis in patients over 50 and is classified as a large-vessel vasculitis affecting the aorta and its major branches, including the carotid, vertebral, ophthalmic, and temporal arteries. Granulomatous inflammation targets the internal elastic lamina and intima-media junction. Visual loss occurs due to involvement of the ophthalmic/posterior ciliary arteries. GCA is a large + medium vessel vasculitis; polyarteritis nodosa is medium-vessel; MPA/EGPA are small vessel.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.