Alopecia areata, endocrine function, and autoantibodies in patients 16 years of age or younger.

Forty-five children with alopecia areata were prospectively studied by means of both clinical and laboratory evaluation for evidence of endocrine diseases and autoantibodies. Twenty-four percent had an abnormality as determined by one or more thyroid function studies (thyroxine, triiodothyronine, and thyroid-stimulating hormone) and/or elevation of microsomal antibody levels. In 16%, smooth muscle antibody was present, and in 4%, parietal cell antibody was present. Routine thyroid function testing is recommended for all children with alopecia areata.