Systemic Vasculitis

Carol A. Langford

RAPID BOARD REVIEW—KEY POINTS TO REMEMBER:

Vasculitis is defined by the presence of blood vessel inflammation. It is a histologic feature shared by a diverse range of diseases that may be characterized by differing patterns of organ involvement, severity, treatment, and outcome.
The signs and symptoms of vasculitis can be nonspecific, related to organ and tissue ischemia, and/or reflective of generalized inflammation, which is influenced by the underlying diagnostic cause.
Antineutrophil cytoplasmic antibodies (ANCAs) have not been found to be a reliable measure of disease activity, and changes in ANCA level alone should not be used to guide treatment decisions.
The therapy of systemic vasculitis varies depending on the type of vasculitis, site of organ involvement, and severity. Certain types of vasculitis may be self-limiting and merely require careful monitoring, while others necessitate aggressive immunosuppressive treatment.

Giant Cell Arteritis

Large + medium-vessel (predominantly cranial) granulomatous arteritis
Almost exclusively >50 years, more common in women, rarely in African Americans
Diagnosis = clinical features + elevated ESR + positive temporal artery biopsy
Glucocorticoid therapy should be started immediately in order to protect vision.
Aspirin 81 mg daily may reduce cranial ischemic complications.

Takayasu Arteritis

Large-vessel granulomatous arteritis (aorta, its main branches, pulmonary arteries)
Predominantly in young women
Diagnosis = clinical features + arteriographic imaging (MRA, CT arteriography, or catheter-directed dye arteriography) revealing aneurysm formation (aortic root with aortic regurgitation) or stenosis (especially abdominal aorta)
Glucocorticoids, methotrexate, infliximab

Polyarteritis Nodosa

Small- and medium-sized muscular arteries vasculitis (not capillaries, or venules)
Men:women ˜2:1, typically between 40 and 60 years
Diagnosis = clinical features (NOT glomerulonephritis (GN) or pulmonary hemorrhage) + arteriographic findings or biopsy-proven vasculitis (multiple microaneurysms)
Prednisone and cyclophosphamide for life-threatening cases

Wegener’s Granulomatosis

Granulomatous inflammation ± small vessel vasculitis
Diagnosis = involvement of the upper and lower respiratory tract and kidneys + biopsy
ANCA positive 80% to 100% patients—80% to 95% against proteinase-3 (PR-3) (i.e., cANCA)
High-dose prednisone + cyclophosphamide (CYC) or rituximab in severe cases. After 3 to 6 months switch to methotrexate or azathioprine for remission maintenance
Trimethoprim-sulfamethoxazole decreases the rate of upper respiratory flares

Microscopic Polyangiitis

Small ± medium-vessel nongranulomatous vasculitis
Diagnosis = pulmonary (alveolar hemorrhage) and renal involvement (rapidly progressive GN) + biopsy
pANCA directed against myeloperoxidase (MPO) 50% to 80% positive
Treatment similar to the one for GPA

Eosinophilic Granulomatosis with Polyangiitis (Churg-Strauss Syndrome)

Small- to medium-size vessel necrotizing vasculitis, with eosinophils, and granulomas
Diagnosis = asthma + clinical features of vasculitis (palpable purpura or skin infarction and other organ involvement) + eosinophilia (>1,500 cells/mm³)
ANCA positive <40% of patients and are typically anti-MPO-ANCA
▪ High-dose glucocorticoids. CYC for refractory or life-threatening cases