GHmangel

GHmangel, or growth hormone deficiency, is a condition characterized by insufficient production or action of growth hormone (GH) by the pituitary gland, or impaired GH signaling in the body. GH is produced in the anterior pituitary and stimulates growth and metabolism; its release is regulated by hypothalamic releasing and inhibitory hormones, notably GHRH and somatostatin.

Causes of GHmangel include congenital pituitary defects, acquired pituitary disease or injury, brain irradiation, and genetic mutations affecting GH synthesis, GH receptors, or regulatory pathways. Defects can be isolated or part of broader pituitary hormone deficiencies. Hypothalamic deficiencies can also reduce GH release. In some cases, the cause remains idiopathic after evaluation.

Clinical features vary by age. In children, GHmangel typically presents with short stature and slow growth velocity, sometimes with delayed puberty or other pituitary deficiencies. In adults, symptoms include reduced muscle mass, increased fat, decreased bone density, fatigue, and impaired quality of life.

Diagnosis involves a combination of clinical assessment and laboratory tests. Serum IGF-1 levels are measured as a screening tool and are usually low for age in GHmangel. GH stimulation tests (such as the insulin tolerance test or glucagon test) assess the pituitary's capacity to secrete GH. Brain MRI is often performed to identify pituitary or hypothalamic abnormalities, and other causes of short stature are excluded.

Treatment most commonly uses recombinant human growth hormone (rhGH) given by daily subcutaneous injections. In children, therapy aims to normalize growth velocity and achieve an appropriate final height, with dosing guided by weight and IGF-1 levels. In adults, GH replacement can improve lean body mass, bone density, and well-being, but requires careful monitoring for metabolic effects and potential adverse events. Regular follow-up includes growth response (in children), IGF-1 targeting, metabolic parameters, and assessment of adverse effects.