Immune Vasculitis by Vessel Size, Including Kawasaki Disease

Takayasu arteritis is also called pulseless disease or aortic arch syndrome. It is common in Asia, especially among young and middle-aged females. Granulomatous inflammation can produce arterial thrombosis, stenosis, or aneurysm.

Additional findings in this differential include a preceding history of asthma, involvement of multiple organ systems, livedo reticularis, and hyperpigmentation.

Kawasaki disease is also called lymph node syndrome, mucocutaneous node disease, or infantile polyarteritis. It affects the skin, mucous membranes, lymph nodes, and blood vessel walls. Its most serious effect is cardiac involvement with severe aneurysmal dilations.

Giant cell arteritis, also called temporal or cranial arteritis, is chronic and occurs primarily in elderly adults and is more common in females. It usually affects the carotid system, especially cranial arteries, but may involve the aorta and its branches, coronary arteries, and peripheral arteries. Veins are rarely involved. Histology shows granulomatous inflammation of the intima and inner media.

• Aortic involvement with palpable purpura and panarteritis
• Absent upper-extremity pulses, including an absent radial pulse
• Fever, weight loss, arthralgias, and fatigue
• Anemia and increased ESR
• Visual loss or field defects and retinal hemorrhages
• Headache, pulsating chest pain, and hypertension

Classic polyarteritis nodosa is a necrotizing vasculitis of small- and medium-sized muscular arteries; renal and visceral arterial involvement is characteristic, and intimal proliferation occurs. It does not involve the pulmonary arteries. Its renal pathology is predominantly arteritis without glomerulonephritis, distinguishing it from microscopic polyangiitis.

Diagnosis classically requires five days of fever plus four of five findings:

1. Erythema of the lips or oral cavity, or cracked lips
2. Rash
3. Swelling or erythema of the hands or feet
4. Conjunctival injection
5. A cervical lymph node at least 15 millimeters in size

Strawberry tongue may be seen.

• Severe headache, the most common presentation, especially temporal or occipital, with scalp tenderness
• Amaurosis fugax, diplopia, scotoma, ptosis, or blurred vision
• Claudication of the masseter, temporalis, or tongue muscles
• Blindness from ischemic optic neuropathy
• Swollen, tender, nodular temporal arteries
• Bruits over large vessels

Steroids are the treatment of choice.

Hepatitis B surface antigen is detected in approximately 20–30% of patients with systemic vasculitis (up to 30%). Hypergammaglobulinemia may be present. Positive ANCA titers, usually p-ANCA, occur in fewer than 20%. Confirm classic PAN by demonstrating characteristic vasculitis on biopsy.

High-dose intravenous immunoglobulin is standard treatment. Marked improvement usually occurs within 24 hours. If fever does not respond, consider another dose. IVIg is most useful within the first seven days of fever for preventing coronary artery aneurysm.

During active disease, ESR is usually markedly elevated, often above 100 mm/h by Westergren, but is normal in about 1% of patients. Normochromic, normocytic anemia is common and may be profound. Alkaline phosphatase may be elevated. Other nonspecific findings include polyclonal hyperglobulinemia and leukocytosis.

Microscopic polyangiitis is pauci-immune necrotizing vasculitis of capillaries, venules, or arterioles, although necrotizing arteritis may also affect small and medium arteries. Glomerulonephritis is very common, occurring in 90%, and pulmonary capillaritis often occurs. ANCA is strongly associated, usually p-ANCA, although c-ANCA is reported.

Begin aspirin at a high dose until fever subsides, then continue a low dose at home, usually for two months, to prevent blood clots. Except in Kawasaki disease, aspirin is normally avoided in children because aspirin is associated with Reye syndrome. Corticosteroids may be used when other treatment fails or symptoms recur.