|
Medical Definition of Familial goiter
1. A group of heritable thyroid disorders in which goiter is commonly apparent first during childhood; often associated with skeletal and/or mental retardation, and with other signs of hypothyroidism that may develop with age. Various types of familial goiter have been identified: 1) iodide transport defect, in which the gland is unable to concentrate iodide; 2) organification defect, in which the iodination of tyrosine is defective; 3) Pendred's syndrome; 4) coupling defect, in which cretinism results from defective coupling of iodotyrosines to form iodothyronines; 5) iodotyrosine deiodinase defect, in which deiodination of iodotyrosine is defective, considerable glandular loss of these hormonal precursors occurs, and cretinism may be present; 6) plasma iodoprotein disorder, in which an abnormal iodinated serum protein that is insoluble in acidic butanol is present; 7) hereditary hyperthyroidism. (05 Mar 2000)