Large Vessel Vasculitis

Info

🌱 來自: Huppert’s Notes

Large Vessel Vasculitis🚧 施工中

Large Vessel Vasculitis

Temporal arteritis/giant cell arteritis (GCA)

•   Pathogenesis: Not fully elucidated; association with HLA-DRB*04 suggests cell-mediated autoimmunity resulting in granulomatous inflammation of vessel walls. Most commonly affects the major aortic branch vessels or secondary branch vessels (e.g., external carotid, subclavian, axillary, temporal).

•   Epidemiology: Incidence of 10–20/100,000 individuals annually in the United States; F:M = 2:1

•   Clinical features: Headache, scalp pain, jaw claudication. Ophthalmic artery involvement may present with amaurosis fugax and can cause blindness. 50% of patients with GCA also have PMR.

•   Diagnosis:

-   New headache in an adult ≥50 yr with temporal artery tenderness, ESR ≥50 mm/hr (although normal ESR does not exclude the diagnosis), and temporal artery biopsy showing mononuclear cell infiltration of the vessel wall, potentially with giant multinucleated macrophages and granulomas.

-   Do not delay steroids to get biopsy! Diseased tissue remains abnormal for up to two weeks after treatment initiation.

•   Treatment:

-   Prednisone: High-dose prednisone 1 mg/kg/day (started immediately without waiting for biopsy results) and ASA 81 mg daily. Followed by prolonged, slow steroid taper

-   Tocilizumab: Anti-IL-6 receptor monoclonal antibody, given weekly or biweekly. Tocilizumab + prednisone resulted in higher rate of glucocorticoid-free remission at 1 yr compared to prednisone alone (53–56% remission vs. 18%) (GiACTA study New Engl J Med 2017)

Takayasu’s arteritis

•   Pathogenesis: Histology of vascular lesions is similar to GCA, but typically involves larger vessels, most commonly the aorta followed by the subclavian, common carotid, renal, and pulmonary arteries

•   Epidemiology: Prevalence is 40/million individuals in Japan and 4.7–8/million individuals elsewhere. Predominantly affects young women.

•   Clinical features: Involvement of the subclavian arteries can cause limb claudication, absent or reduced brachial artery pulses, subclavian bruits, blood pressure discrepancies between arms. Carotid involvement can cause neck pain and tenderness to palpation on exam. ESR and CRP are typically elevated.

•   Diagnosis: MR angiography demonstrates thoracic vessel stenoses and vessel wall inflammation

•   Complications: Limb ischemia, aortic aneurysm, aortic regurgitation, stroke, renal artery stenosis with secondary hypertension

•   Treatment: High-dose prednisone (1 mg/kg) with prolonged slow taper. May need surgery or angioplasty to recannulate stenosed vessels, but this should be deferred until resolution of active vessel inflammation.