The Pituitary and Primary Hypothyroidism

Abstract
Enlargement of the pituitary gland in longstanding myxedema has been found in pathologic material obtained by autopsy. However, antemortem recognition of a causal relationship between hyperplasia of the pituitary and adult-acquired primary hypothyroidism has been reported infrequently. Our observations suggest that target gland failure, perhaps primary hypothyroidism in particular, can lead to pituitary enlargement more frequently than formerly supposed. Furthermore, an overlap of secretory signals within the hypothalamus or at the level of the hypophysis may influence the clinical expression of the syndrome of pituitary hyperplasia and hyperfunction in patients with specific target gland failure.