Editing Growth hormone (section)

==Clinical significance==

===Excess===
The most common disease of GH excess is a pituitary tumor composed of somatotroph cells of the anterior pituitary. These somatotroph [[adenoma]]s are benign and grow slowly, gradually producing more and more GH. For years, the principal clinical problems are those of GH excess. Eventually, the adenoma may become large enough to cause headaches, impair vision by pressure on the optic nerves, or cause deficiency of other pituitary hormones by displacement.{{cn|date=November 2024}}

Prolonged GH excess thickens the bones of the jaw, fingers and toes, resulting in heaviness of the jaw and increased size of digits, referred to as [[acromegaly]]. Accompanying problems can include sweating, pressure on nerves (e.g., [[carpal tunnel syndrome]]), muscle weakness, excess [[sex hormone-binding globulin]] (SHBG), insulin resistance or even a rare form of [[Diabetes mellitus type 2|type 2 diabetes]], and reduced sexual function.{{cn|date=November 2024}}

GH-secreting tumors are typically recognized in the fifth decade of life. It is extremely rare for such a tumor to occur in childhood, but, when it does, the excessive GH can cause excessive growth, traditionally referred to as [[gigantism|pituitary gigantism]].{{cn|date=November 2024}}

Surgical removal is the usual treatment for GH-producing tumors. In some circumstances, focused radiation or a GH antagonist such as [[pegvisomant]] may be employed to shrink the tumor or block function. Other drugs like [[octreotide]] (somatostatin agonist) and [[bromocriptine]] ([[dopamine agonist]]) can be used to block GH secretion because both somatostatin and [[dopamine]] negatively inhibit GHRH-mediated GH release from the anterior pituitary.<ref>{{cite journal | vauthors = Varlamov EV, McCartney S, Fleseriu M | title = Functioning Pituitary Adenomas - Current Treatment Options and Emerging Medical Therapies | journal = European Endocrinology | volume = 15 | issue = 1 | pages = 30–40 | date = April 2019 | pmid = 31244908 | pmc = 6587904 | doi = 10.17925/EE.2019.15.1.30 }}</ref>

===Deficiency===
{{Main|Growth hormone deficiency}}

The effects of [[growth hormone deficiency|growth hormone (GH) deficiency]] vary depending on the age at which they occur.  Alterations in [[somatomedin]] can result in growth hormone deficiency with two known mechanisms; failure of tissues to respond to [[somatomedin]], or failure of the [[liver]] to produce somatomedin.<ref name="Ignatavicius-2015">{{Cite book|title=Medical-Surgical Nursing: Patient-Centered Collaborative Care| vauthors = Ignatavicius D, Workman L |publisher=Saunders|year=2015|isbn=978-1455772551|edition=8|pages=1267}}</ref>  Major manifestations of GH deficiency in children are [[growth failure]], the development of a [[short stature]], and delayed sexual maturity.  In adults, somatomedin alteration contributes to increased [[osteoclast]] activity, resulting in weaker bones that are more prone to [[pathologic fracture]] and [[osteoporosis]].<ref name="Ignatavicius-2015" /> However, deficiency is rare in adults, with the most common cause being a [[pituitary adenoma]].<ref name="Molitch et al. 2006">{{cite journal | vauthors = Molitch ME, Clemmons DR, Malozowski S, Merriam GR, Shalet SM, Vance ML, Stephens PA | title = Evaluation and treatment of adult growth hormone deficiency: an Endocrine Society Clinical Practice Guideline | journal = The Journal of Clinical Endocrinology and Metabolism | volume = 91 | issue = 5 | pages = 1621–34 | date = May 2006 | pmid = 16636129 | doi = 10.1210/jc.2005-2227 | doi-access = free }}</ref>  Other adult causes include a continuation of a childhood problem, other structural lesions or [[Injury|trauma]], and very rarely idiopathic GHD.<ref name="Molitch et al. 2006" />

Adults with GHD "tend to have a relative increase in fat mass and a relative decrease in muscle mass and, in many instances, decreased energy and quality of life".<ref name="Molitch et al. 2006"/>

Diagnosis of GH deficiency involves a multiple-step diagnostic process, usually culminating in GH stimulation tests to see if the patient's pituitary gland will release a pulse of GH when provoked by various stimuli.{{cn|date=November 2024}}