Abnormal function of endocrine pancreas and anterior pituitary in Friedreich's ataxia. Studies in a family.

A family had three siblings affected with classic Friedreich's ataxia. One sibling died at age 20 with fulminant diabetic ketoacidosis. The other two affected siblings are identical twin sisters without clinical diabetes but with an abnormality in the metabolism of exogenously administered glucose. These twins also have abnormal hypothalamic-pituitary control of prolactin and possibly of growth-hormone secretion. This study extends the previous reports of endocrine deficienceis associated with Friedreich's ataxia. The mechanisms underlying this association are undetermined but could represent pleiotropic effects of the Friedreich's ataxia gene or secondary manifestations of the primary central nervous system degeneration, or both.