Autoimmunity as a possible cause of growth hormone deficiency.

A possible autoimmune aggression to pituitary somatotrophs has been suggested by the occurrence of antipituitary antibodies (APA) directed against GH-secreting cells in some cases of GH deficiency (GHD) both in adults and in children and in some patients with autoimmune poliendocrine syndrome. We also detected APA in some patients with idiopathic short stature (ISS) and suggested that the presence of these antibodies could identify those of them prone to develop GHD. In fact, patients with ISS, resulted positive for APA at the first observation, during a longitudinal follow-up showed an impaired GH response to the stimuli in subsequent years suggestive of acquired GHD. Also in such patients we demonstrated that the target of APA were the somatotrophs and that an autoimmune attack to these cells may be the underlying cause of hormonal impairment in several children with GHD positive for APA. In this connection we suggested that in these patients an early iso-hormonal therapy with recombinant GH may be useful to interrupt or delay the progression towards a clinical GHD.