A case of panhypopituitarism with normal height manifesting the transection of the pituitary stalk and the formation of the ectopic and eutopic posterior lobes

Abstract

A 33-year-old man with hypopituitarism is documented. He was born at breech presentation without asphyxia. He was the shortest in his class throughout his school days. He kept slowly growing and reached 172.8 cm at the age of 33. He was devoid of secondary sexual characteristics. Endocrinological studies showed panhypopituitarism with elevated levels of plasma TSH (15.0 microU/ml). TRH administration resulted in a marked increase in plasma TSH. Posterior pituitary function was normal. MR imaging showed transection of the pituitary stalk and the presence of ectopic and eutopic posterior lobes. The replacement of corticosteroid was initiated, and exaggerated response of TSH to TRH disappeared. Delayed bone maturation due to hypogonadism and hypothyroidism was one of the reasons why he had normal height without GH therapy. The significance of his peculiar MRI findings remains to be determined.