Reports of two cases of selective adrenocorticotropin (ACTH) and growth hormone (GH) deficiency: differential diagnosis from cases with isolated ACTH deficiency associated with transient GH insufficiency.
An acquired partial pituitary insufficiency with selective ACTH and GH deficiency was demonstrated in two men aged 47 and 54, for which the clinical course over many years corresponds to Addison's disease. In one of the 2 cases, antibodies to anterior pituitary cell membrane, assayed by an immunofluorescence method with GH3 cells (rat GH and prolactin secreting cell) and AtT-20 cells (mouse ACTH secreting cell) as antigens, were positive. We also present a 55-year-old man with isolated ACTH deficiency associated with transient GH deficiency. In this case, hydrocortisone replacement corrected his subnormal, pre-therapy GH response to insulin tolerance and glucagon propranolol tests, although there was no response of serum GH to L-dops and arginine stimulation test before therapy. Selective ACTH and GH deficiency are very rare and the finding of transient GH insufficiency in a patient with isolated ACTH deficiency suggests that repeated testing while on hydrocortisone replacement therapy is of great diagnostic importance in order to distinguish between selective ACTH and GH deficiency and isolated ACTH deficiency accompanied by transient GH insufficiency.