Diagnostic considerations in ataxia-telangiectasia.

13 children with ataxia-telangiectasia were followed for 6 years. Unlike previously reported cases, these patients had progressive, debilitating neurological disease and slight pulmonary or infectious symptoms. Immunological dysfunction was variable and endocrinological defects were absent. Oculomotor findings, alpha-fetoprotein levels, and the incidence of chromosomal breakage were the most consistent parameters in the diagnosis of the condition. This disease should be considered in any patient with chronic ataxia, regardless of immunological findings or whether he has a history of infections.