Primary hypothyroidism, empty sella, and hypopituitarism

Abstract

Primary hypothyroidism may be associated with enlargement of the sella turcica, thought to represent hypertrophy and hyperplasia of the pituitary gland in response to lack of negative feedback of thyroid hormones) Thyroid ablation in mice and rats produces a progressive sequence of pituitary hyperplasia, enlargement, nodularity, and adenoma, which can be prevented by thyroid hormone treatment. 2 Subtle visual field defects resulting from pituitary enlargement have been documented in a majority of patients with primary hypothyroidism3; severe visual field loss and blindness have also been reported. 4's These changes may be reversible with thyroid hormone replacement: although in some cases craniotomy has been necessary.4,5 As might be expected, pituitary hormone alterations have also been documented in primary hypothyroidism, 7 and hypopituitarism, both transient 8 and permanent: has been reported. An empty sella is a reported outcome in some of these patients) ~ H We report an l 1-year-old boy with primary hypothyroidism associated with enlargement of the sella and pituitary gland, in whom an empty sella and hypopituitarism developed after thyroid hormone treatment. To our knowledge, this is the first child reported with this sequence of changes documented by CT scan