[Giant cell arteritis and polymyalgia rheumatica presenting as subclavian artery obstruction]

Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are common diseases in the elderly. The arteritis usually affects medium sized vessels, but large vessel involvement can also occur leading to arm claudication, bruits, loss of pulses and pallor of the upper extremities. The differential diagnosis of large vessel arteritis includes atherosclerosis and Takayasu's disease. Atherosclerosis, which affects patients of similar age to GCA is usually confined to the lower limbs and can be differentiated on the basis of the clinical setting and investigations such as the ESR, arteriography and temporal artery biopsy. Takayasu's arteritis' although histologically and arteriographically indistinguishable from GCA, is predominantly a disease of young women. A patient is described who presented with upper limb ischemia. A clinical examination revealed absence of right radial pulses and presence of murmurs at level of the carotids. The blood pressure was unrecordable in the upper right limb. The ESR was 102 mm/hr and the C-reactive protein was 11.66 mg/dl. A selective arteriography of the aortic arch and its branches revealed a right subclavian artery obstruction with good collateral circulation and a left subclavian artery stenosis. The biopsy of left temporal artery showed a typical GCA in acute stage. Treatment with prednisolone 30 mg/day was started and four weeks later, the ESR had fallen to normal. In addition this case confirms that PMR implies a systemic arteritis.