Endocrine Abstracts

Adult GH deficiency (AGHD) is a common sequela in patients with pituitary or brain tumors or in patients with a history of traumatic brain injury or cranial irradiation. In addition, approximately one third of children who were diagnosed with GH deficiency will remain GH deficient as adults. Since AGHD is characterized by diminished cardiovascular health, abnormal body composition, decreased muscle strength and aerobic capacity, poor quality of life, and increased mortality, it is important to make this diagnosis and to offer appropriate GH replacement therapy to these patients. In order to do so, it is necessary to select the appropriate patients to test and to understand how to perform and interpret the panoply of tests that have been devised to make the correct diagnosis. In patients with panhypopituitarism or in adults with a history of childhood-onset GHD due to a genetic or an identified organic cause, a low serum IGF-I is sufficient to make the diagnosis of AGHD. In all other patients, a growth hormone stimulation test is required, since a single random measurement of GH, which is secreted in a pulsatile fashion, lacks precision and because a significant number of patients with AGHD will have normal levels of IGF-I. The various GH stimulation tests and the controversies regarding their interpretation will be discussed in the context of identifying those patients who are at high risk of having AGHD.