Diagnosis of Takayasu's arteritis

Diagnosis

To assist in diagnosis, American College of Rheumatology (ACR) has established a diagnostic criterion for Takayasu arteritis. The patient needs to meet 3 out of 6 criteria for the diagnosis of takayasu arteritis.

• Age at the onset of disease <40 years

• Claudication of the extremities
• Decreased or absent brachial artery pulse in one or both arms
• Difference of at least 10 mmHg in systolic blood pressure in between the arms
• Bruit over either one or both subclavian arteries or abdominal artery
• Arteriography demonstration of narrowing of aorta or its primary branches, not due to atherosclerosis, fibromuscular dyaplasia or other causes.

Symptoms

The disease can be divided into two phases; the Initial phase is pre-pulseless phase, in which patients presents which non-specific constitutential symptoms of vasculitis, which may include the following symptoms.

• Fatigue
• Fever of unknown origin
• Weight loss
• Myalgia
• Arthralgia

With progression of the disease and involvement of the branches of aorta, the specific signs appear secondary to narrowing/occlusion of the branches of aorta.

• Involvement of Subclavian Artery is common and leads to claudication of upper extremities ( pain with activity). The stenosis of subclavian artery sometimes leads to Subclavian Steel Syndrome. In this phenomenon, the stenosis of subclavian artery, proximal to the origin of Vertebral Artery leads to retrograde flow of blood from the vertebral artery back to subclavian artery during exercise, secondary to vasodilation of blood vessels. The retrograde flow of blood from the vertebral artery back towards subclavian compromises blood flow in Posterior Cerebral bed, leading to various neurological symptoms including presyncope/syncope.

• Involvement of carotid and vertebral arteries leads to headache, vertigo, syncope, convulsions and dementia.

• Involvement of coronary arteries leads to chest pain, angina which may progress to myocardial infarction.

• Involvement of ascending aorta may cause aortic regurgiatation

• Skin lesions resemble erythema nodosum, erythema multiforme, pyoderma gangrenosum.

• In rare instances, the disease may involve abdominal, pulmonary vessels.

In advance stages of the disease, the occlusion of the vessels to the extremities may can ischemic ulcerations. Due to chronic nature of the disease, collateral circulation develops in the affected area.