An adult case of neurohypophyseal ectopy presenting ACTH deficiency and partial GH deficiency

A case of ACTH deficiency and partial GH deficiency associated with neurohypophyseal ectopy is described. A 42-year-old woman of short stature was admitted for hypoglycemic coma. The patient had hypocortisolemia, an increase in urinary 17-OHCS after consecutive injections of ACTH-Z, and a low plasma ACTH level which showed no response to corticotropin-releasing factor. This indicated the presence of ACTH deficiency. The plasma GH level showed a blunted response to insulin-induced hypoglycemia, but its response to GRF was preserved. Other hypothalamo-pituitary axes were intact. T1-weighted magnetic resonance imaging demonstrated ectopic neurohypophyseal tissue and a tiny anterior pituitary remnant. ACTH deficiency and partial GH deficiency might have developed as a consequence of pituitary stalk injury and inadequate regeneration of the anterior lobe.