Acromegaly - excessive growth hormone

 

Acromegaly is a consequence of a pituitary tumor.

(It is not a general consequence of brain injury.)

As a result of a tumor in the pituitary gland, too much growth hormone is produced with the result that body parts and / or organs grow out of proportion. This excessive growth of body parts is called acromegaly.

It is a rare condition that occurs in about four in a million people.

The pituitary gland is a gland with the size of a pea that lies at the bottom of a bony protection (the Turkish saddle - sella turcica) at the bottom of the brain behind the eye sockets.
The pituitary gland provides the fluid balance in the body, regulates the temperature, the male and female hormone, the thyroid gland, but also controls the adrenal glands. A healthy pituitary gland controls the adrenal cortex with adrenal cortex stimulating hormone (ACTH) to create the stress hormone cortisol.

The pituitary gland is in turn controlled by the hypothalamus.

A tumor in the pituitary gland may disrupt the production of one or more of the pituitary hormones, or lead to overproduction.

 

 

The pituitary gland (the red dot) is as small as a pea but it is the most important in the human body.

 

Image is from Wikimedia Commons. Anatomography, website maintained by Life Science Databases(LSDB) {{ja|1=脳下垂体。 画像はLife Science Databases(LSDB)のAnatomographyというサイトより。}} |Source=from Anatomo
https://commons.wikimedia.org/wiki/File:Pituitary_gland_small.gif

Growth hormone

Acromegaly occurs when a tumor develops in the part of the pituitary gland that produces growth hormone. Acromegaly is in most cases not congenital and in less than 1% it is hereditary.

The hormone levels in the blood can be measured (IGF-I insulin like growth factor I content in the blood). The diagnosis can be confirmed by an MRI scan of the pituitary gland.
In a hormone-producing tumor, treatment is first sought with medication. If this does not provide sufficient improvement, surgery will have to be considered, after which the overproduction of growth hormone will decrease or stop.

 

Eye nerve in the pinch

It can occur that the pituitary tumor pushes against the optic nerves causing problems with vision. The facial nerves can be damaged. That is why people with a pituitary tumor receive a visual field test. There it is investigated whether someone can observe small lights on the sides of the field of view.

Problems with the field of view is one of the reasons to remove the tumor.

 

Complaints (with insidious onset)

The following symptoms can usually develop over a period of years and are quite general in nature, such as sleep problems and fatigue, so that a pituitary tumor is not immediately thought of.

  • Fatigue and weakness
  • Insomnia
  • Headache
  • Difficulty seeing, blurred vision or field of vision loss
  • Excessive perspiration and hot flashes (especially with women)
  • Greasy skin
  • Growth of hands, fingers and feet (people notice this by the size of their ring, glove or shoe)
  • Teeth that stand a bit further apart
  • Thickened hard nails
  • Raw skin that feels like dough and limbs
  • Large pores
  • Weight gain, obesity
  • Tingling in the hands (not in all people with acromegaly)
  • Pain in the hands, peripheral neuropathy, carpal tunnel syndrome (not in all people with acromegaly)
  • Growth of the lower jaw, nose or facial folds making the face look different
  • Diabetes due to the anti-insulin effect of growth
  • Hormone / insulin resistance (± 1 / 3rd of people with acromegaly)
  • Irregular menstruation (not in all women with acromegaly)
  • Erection problems (not in all men with acromegaly)
  • Impotence (not in all men with acromegaly)
  • Infertility (not in all people with acromegaly)
  • Joint wear (not in all people with acromegaly)
  • In case acromegaly arises for the 18th year of life, giant growth (gigantism) can follow
  • Internal organs can be greatly enlarged
  • Depression (not in all people with acromegaly)
  • Delusions (not in all people with acromegaly)
 

Untreated acromegaly

Untreated acromegaly can lead to

  • Type 2 diabetes
  • High blood pressure (hypertension)
  • Heart muscle disease (cardiomyopathy)
  • Joint inflammation (arthritis)
  • Bowel polyps that can pass to a malignant form of colon cancer

 

Treatment

Often there is a combination of treatment options.

  • Medication for normalizing growth hormone
  • Radiation therapy to damage the genetic material of the tumor cell)
  • Operation after which follow-up treatment with medication or radiation can follow. A surgery usually takes place through an endoscopy behind the upper lip through the nasal cavity (transphenoidal surgery) or through the nostril but also through a hatch in the skull (trepanation).

 

Perspective

In case the treatment has effect, the symptoms can be greatly reduced, although it can take years for some to be noticeable. People return to normal weight.
Not all symptoms can be reversed, such as the enlarged jaw, and the enlarged body ends.
The endocrine system can be permanently disturbed.
Brain injury effects can occur as a result of the operation, for example overstimulation and other invisible effects of NAH. It also happens that people have neurological function loss..

 


 

More information

Wikipedia

Mayo clinic

 

Sources

Ahmed S1, Elsheikh M, Stratton IM, Page RC, Adams CB, Wass JA.

Outcome of transphenoidal surgery for acromegaly and its relationship to surgical experience. Clin Endocrinol (Oxf). 1999 May;50(5):561-7.

Anagnostis P1, Efstathiadou ZA, Polyzos SA, Adamidou F, Slavakis A, Sapranidis M, Litsas ID, Katergari S, Selalmatzidou D, Kita M. (2011)

Acromegaly: presentation, morbidity and treatment outcomes at a single centre.

Int J Clin Pract. 2011 Aug;65(8):896-902. doi: 10.1111/j.1742-1241.2011.02682.x. Epub 2011 Jun 16.

Crespo I, Santos A, Resmini E, Valassi E, Martínez-Momblán MA, Webb SM. Eur Endocrinol. (2013) Mar; 9(1):32-36. Epub 2013 Mar 15.Improving Quality of Life in Patients with Pituitary Tumours.


Diaz-Thomas, A., MD, MPH, Shim, M., MD, Gigantism and Acromegaly (2017) Medscape https://emedicine.medscape.com/article/925446-overview


Hall, J.E., 2006, Pocket Companion to Textbook of Medical Physiology,  Elsevier Inc

 

Marieb,E.N., Hoehn, K. 2007, Human Anatomy & Physiology, Pearson/Benjamin Cummings

NHS Acromegaly (2018)  https://www.nhs.uk/conditions/acromegaly/

 

Ben Shlomo, A., Melmed, S., Acromegaly (2007 en 2008) Endocrinology  and Metabolism Clinic North Am. 2008 Mar;37(1):101-22, viii. doi: 10.1016/j.ecl.2007.10.002.
Thibodeau, G.A., Patton KT 2007, Anatomy & Physiology, Mosby/Elsevier