Granulomatous inflammation of the aortic arch and proximal great vessels is known as Takayasu arteritis which this patient has. Temporal arteritis (also known as giant cell arteritis) is also characterized by granulomatous inflammation of large arteries and is most similar to Takayasu arteritis.
Takayasu arteritis and giant cell arteritis make up the large vessel vasculitides. While histologically both are classified by granulomatous inflammation, the presentations differ clinically. Giant cell arteritis is generally seen in adults over 50 years of age and most commonly affects the temporal artery. It presents with jaw claudication, headache, facial pain, or vision loss and is associated with polymyalgia rheumatica.
As reviewed by Sharma et al., first-line treatment for Takayasu arteritis and giant cell arteritis is with steroids. Adjunct agents include methotrexate and azathioprine. Bisphosphonate and aspirin are recommended for bone protection with long-term steroid use and prevention of cerebrovascular and cardiovascular ischemic events, respectively.
According to Hunder et al., definitive diagnosis of giant cell arteritis requires biopsy of at least 3 cm of the temporal artery (60-90% sensitivity, 100% specificity). Alternatively, using American College of Rheumatology (ACR) criteria, presence of 3 or more of the following criteria diagnoses temporal arteritis with 93.5% sensitivity and 91.2% specificity: age at disease onset > 50 years, new headache, temporal artery abnormality (tenderness or decreased pulsation unrelated to cervical arteriosclerosis), ESR > 50 mm/hour, abnormal artery biopsy.
Illustration A is an MR angiogram with evidence of Takayasu arteritis. It shows significant stenosis of the right common carotid artery at its origin (small arrow). The left subclavian artery has two stenotic segments (large arrows) with a small area of poststenotic dilatation in between.
Illustration B demonstrates the histopathology of giant cell arteritis with predominantly medial inflammation involving most of the circumference of the artery, accompanied by intimal proliferation with luminal stenosis.
Answer 2: Polyarteritis nodosa is an immune-complex mediated vasculitis with fibrinoid necrosis affecting renal, coronary, and mesenteric arteries.
Answer 3: Kawasaki disease is acute, self-limiting necrotizing vasculitis.
Answer 4: Buerger's disease is associated with heavy smoking.
Answer 5: Infectious vasculitis affects skin and is a result of an immune reaction to a pathogen.
Sharma P, Sharma S, Baltaro R, Hurley J. Systemic vasculitis. Am Fam Physician. 2011 Mar 1;83(5):556-65. Review. PubMed PMID: 21391523.
PMID:21391523 (Link to Abstract)
Hunder GG, Bloch DA, Michel BA, Stevens MB, Arend WP, Calabrese LH, Edworthy SM, Fauci AS, Leavitt RY, Lie JT, et al. The American College of Rheumatology 1990 criteria for the classification of giant cell arteritis. Arthritis Rheum. 1990 Aug;33(8):1122-8. PubMed PMID: 2202311.
PMID:2202311 (Link to Abstract)
USMLE World Step 1 QBank Question #452. Copyright © USMLEWorld, LLC 2012.