ataxia-telangiectasia syndrome /təlan″jē·ektā″zhə/ [Gk, ataxia + telos, end, angeion, vessel, ektasis, expansion] , a rare genetic disorder involving deficits in immunoglobulin metabolism that is transmitted as an autosomal-recessive trait. It usually begins in infancy with impaired motor control (ataxia) and progresses slowly with increasing cerebellar degeneration to severe disability. Permanent dilation of superficial blood vessels (telangiectasias) are most prominent on skin surfaces exposed to the sun: ears, face, and bulbar conjunctiva. Intellectual ability seems to stop at the level of 10 years of age in many cases. Affected individuals are susceptible to upper and lower respiratory infections and have an increased risk of malignancy, especially lymphoma. Also called Louis-Bar syndrome.
