Giant Cell Arteritis

Giant cell arteritis and polymylagia rheumatica seem to be a result of the same immunologic disease targeting the synovium, periarticular structures, and medium to large seized arteries in older patients. Regional vasculitic injury dominates the clinical picture (temporal and cranial). Prevalence is 5/10,000 people. Women are more likely than men to be affected and 40% have a history of PMR.

Pathophysiology

Manifestations include histiocytic, lymphocytic, and multinucleated giant-cell infiltrates on the walls of medium/large arteries originating from the aortic arch. Vessels of the head are most often involved, with segmental inflammation and “skip” areas. The internal elastic lamina is fragmented, and intimal proliferation ensures, causing stenosis and ischemia. This change does not cause the aorta to occlude but does make aneurysms and intramural hemorrhage more likely.

1. Cranial Arteritis - Most common, granulomatous vasculitis of the temporal artery, presence of giant cells and high cytokine levels.

2. Large Vessel Arteritis - Large vessel injury with risk of aortic aneurysm and rupture, lack of temporal involvement and high cytokine levels.

3. Arteritis with Systemic Inflammatory Symptoms - T-cell infiltrates, high interleukin levels, fevers, wasting, but no vascular occlusions.

Clinical Presentation/Course

Early symptoms – Headache (piercing/throbbing and localized to the scalp 35% present with this), low-grade temperature (20%), aching/stiffness, PMR (50+%)

Later symptoms – Masseter claudication presenting as jaw pain with chewing, cranial artery tenderness/enlargement, visual problems including blindness (50% if untreated), hearing loss, vertigo, painful dysphagia, neck pain and neurologic deficits

Other symptoms – Aortic arch syndrome and subclavian occlusive disease with Raynaud’s, arm claudication

Chronic illness that may last for years, tends to be self-limited, but course is variable, complications are rare but stopping treatment leads to relapses.

Work Up

History: Jaw claudication/diplopia

PEX: Temporal artery beading, prominence, tenderness, reduced/absent pulses, redness, subclavian bruits, decreased peripheral pulses in UEs

Labs: ESR, IL-6, CRP, Temporal Artery Biopsy

Imaging: Color duplex US, CTA/MRA

Treatment

Prednisone is a first line therapy (40-60 mg per day) to suppress the disease. If there are visual symptoms, IV treatment is needed, usually with Medrol. This should not be delayed for biopsies as it will not affect the results. High dosage therapy should be continued for 2-4 weeks before a slow taper. Relapses can be controlled with addition corticosteroids. Methotrexate adjuvant therapy is of unclear benefit.

1Goroll, Allan H, Mulley, Albert G. Primary Care Medicine: Fifth Edition. Lippincott Williams and Wilkins, 2000. 253.

2Unwin, B, Gilliland, W. “Polymyalgia Rheumatica and Giant Cell Arteritis.” Am Fam Physician. 2006 Nov 1; 74(9):1547-54.

Category: Medicine Notes