Acromegaly causes: Difference between revisions

	Acromegaly Microchapters
Home
Patient Information
Overview
Historical Perspective
Classification
Pathophysiology
Causes
Differentiating Acromegaly from other Diseases
Epidemiology and Demographics
Risk Factors
Screening
Natural History, Complications and Prognosis
Diagnosis
History and Symptoms
Physical Examination
Laboratory Findings
Electrocardiogram
X Ray
CT
MRI
Ultrasound
Other Imaging Findings
Other Diagnostic Studies
Treatment
Medical Therapy
Surgery
Radiation Therapy
Primary Prevention
Secondary Prevention
Cost-Effectiveness of Therapy
Future or Investigational Therapies
Case Studies
Case #1
Acromegaly causes On the Web
Most recent articles
cited articles
Review articles
CME Programs
Powerpoint slides
Images
American Roentgen Ray Society Images of Acromegaly causes All Images X-rays Echo & Ultrasound CT Images MRI
Ongoing Trials at Clinical Trials.gov
US National Guidelines Clearinghouse
NICE Guidance
FDA on Acromegaly causes
CDC on Acromegaly causes
Acromegaly causes in the news
Blogs on Acromegaly causes
Directions to Hospitals Treating Acromegaly
Risk calculators and risk factors for Acromegaly causes

VisualWikitext

Latest revision as of 19:05, 24 August 2017

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Ahmed Elsaiey, MBBCH [2]

Overview

Common causes of acromegaly include pituitary adenoma and acidophil stem cell adenomas. Less common causes of acromegaly include GHRH secreting tumors as hypothalamic tumors, small cell lung cancer, adrenal adenoma, and pheochromocytoma. Other causes include GH secreting tumors as lymphoma and pancreatic islet cell tumor.

Causes

Common Causes

Acromegaly may be caused by:

Pituitary adenoma:^[1]
- It is the most common cause of acromegaly.
- A secretory pituitary adenoma is responsible for acromegaly by excess secretion of the growth hormone and the insulin like growth factor-1 (IGF-1).
Other types of pituitary adenomas causing acromegaly:
- Mixed growth hormone and prolactin cell adenomas
- Acidophil stem cell adenomas
- Mammosomatotroph cell adenomas
- Pleurihormonal adenomas

Less Common Causes

Less common causes of acromegaly include:^[1]

Hypothalamic tumors which secrete growth hormone releasing hormone (GHRH).
Ectopic tumor secretion of GHRH. These tumors include the following:
Ectopic tumor secretion of GH. These tumors include the following:
- Lymphoma
- Pancreatic islet cell tumors

Genetic Causes

Acromegaly is caused by a mutation in the guanine nucleotide stimulatory protein gene which is responsible for pituitary adenomas.^[2]

References

↑ ^1.0 ^1.1 Melmed S, Braunstein GD, Horvath E, Ezrin C, Kovacs K (1983). "Pathophysiology of acromegaly". Endocr Rev. 4 (3): 271–90. doi:10.1210/edrv-4-3-271. PMID 6354702.
↑ Landis CA, Masters SB, Spada A, Pace AM, Bourne HR, Vallar L (1989). "GTPase inhibiting mutations activate the alpha chain of Gs and stimulate adenylyl cyclase in human pituitary tumours". Nature. 340 (6236): 692–6. doi:10.1038/340692a0. PMID 2549426.

Template:WikiDoc Sources

[pmid6354702-1] 1.0 ^1.1 Melmed S, Braunstein GD, Horvath E, Ezrin C, Kovacs K (1983). "Pathophysiology of acromegaly". Endocr Rev. 4 (3): 271–90. doi:10.1210/edrv-4-3-271. PMID 6354702.

[pmid2549426-2] Landis CA, Masters SB, Spada A, Pace AM, Bourne HR, Vallar L (1989). "GTPase inhibiting mutations activate the alpha chain of Gs and stimulate adenylyl cyclase in human pituitary tumours". Nature. 340 (6236): 692–6. doi:10.1038/340692a0. PMID 2549426.

[1]

[2]

@@ Line 1: / Line 1: @@
 __NOTOC__
 {{Acromegaly}}
-{{CMG}}
+{{CMG}}; {{AE}} {{AEL}}
 ==Overview==
+Common causes of acromegaly include [[pituitary adenoma]] and [[acidophil]] [[stem cell]] adenomas. Less common causes of acromegaly include [[GHRH]] secreting tumors as [[hypothalamic]] [[tumors]], [[small cell lung cancer]], [[adrenal adenoma]], and [[pheochromocytoma]]. Other causes include [[GH]] secreting tumors as [[lymphoma]] and [[Pancreatic islet cell tumors|pancreatic islet cell tumor]].
 ==Causes==
-===Pituitary adenoma===
+===Common Causes===
-In over 90 percent of acromegaly patients, the overproduction of GH is caused by a benign tumor of the pituitary gland, called an [[pituitary adenoma|adenoma]]. These tumors produce excess GH and, as they expand, compress surrounding brain tissues, such as the optic nerves. This expansion causes the headaches and visual disturbances that are often symptoms of acromegaly. In addition, compression of the surrounding normal pituitary tissue can alter production of other [[hormones]], leading to changes in menstruation and breast discharge in women and [[impotence]] in men because of reduced [[testosterone]] production.
+Acromegaly may be caused by:
+*[[Pituitary adenoma]]:<ref name="pmid6354702" />
-There is a marked variation in rates of GH production and the aggressiveness of the tumor. Some adenomas grow slowly and symptoms of GH excess are often not noticed for many years. Other adenomas grow rapidly and invade surrounding brain areas or the sinuses, which are located near the pituitary. In general, younger patients tend to have more aggressive tumors.
+**It is the most common cause of acromegaly.
+**A secretory [[pituitary adenoma]] is responsible for acromegaly by excess secretion of the growth hormone and the [[IGF-1|insulin like growth factor-1]] (IGF-1).
+*Other types of [[Pituitary adenoma|pituitary adenomas]] causing acromegaly:
+**Mixed [[growth hormone]] and [[Prolactinoma|prolactin cell adenomas]]
+**[[Acidophil]] [[stem cell]] [[adenomas]]
+**Mammosomatotroph cell adenomas
+**Pleurihormonal adenomas
-Most pituitary tumors arise spontaneously and are not genetically inherited. Many pituitary tumors arise from a genetic alteration in a single pituitary cell which leads to increased cell division and tumor formation. This genetic change, or [[mutation]], is not present at birth, but is acquired during life. The mutation occurs in a gene that regulates the transmission of chemical signals within pituitary cells; it permanently switches on the signal that tells the cell to divide and secrete GH. The events within the cell that cause disordered pituitary [[cell growth]] and GH oversecretion currently are the subject of intensive research.
+===Less Common Causes===
+Less common causes of acromegaly include:<ref name="pmid6354702">{{cite journal| author=Melmed S, Braunstein GD, Horvath E, Ezrin C, Kovacs K| title=Pathophysiology of acromegaly. | journal=Endocr Rev | year= 1983 | volume= 4 | issue= 3 | pages= 271-90 | pmid=6354702 | doi=10.1210/edrv-4-3-271 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=6354702  }}</ref>
+*[[Hypothalamus|Hypothalamic]] tumors which secrete growth hormone releasing hormone (GHRH).
+*[[Ectopic tumor]] secretion of [[GHRH]]. These tumors include the following:
+**[[Small cell lung cancer]]
+**[[Adrenal adenoma]]
+**[[Pheochromocytoma]]
+**[[Thyroid carcinoma]]
+*Ectopic tumor secretion of [[GH]]. These tumors include the following:
+**[[Lymphoma]]
+**[[Pancreatic islet cell tumors]]
-===Other tumors===
+===Genetic Causes===
-In a few patients, acromegaly is caused not by pituitary tumors but by [[tumor]]s of the [[pancreas]], [[lung]]s, and [[adrenal gland]]s. These tumors also lead to an excess of GH, either because they produce GH themselves or, more frequently, because they produce GHRH, the hormone that stimulates the pituitary to make GH. In these patients, the excess GHRH can be measured in the blood and establishes that the cause of the acromegaly is not due to a pituitary defect. When these non-pituitary tumors are surgically removed, GH levels fall and the symptoms of acromegaly improve.
+*Acromegaly is caused by a [[mutation]] in the guanine nucleotide stimulatory [[protein]] [[gene]] which is responsible for [[pituitary adenomas]].<ref name="pmid2549426">{{cite journal| author=Landis CA, Masters SB, Spada A, Pace AM, Bourne HR, Vallar L| title=GTPase inhibiting mutations activate the alpha chain of Gs and stimulate adenylyl cyclase in human pituitary tumours. | journal=Nature | year= 1989 | volume= 340 | issue= 6236 | pages= 692-6 | pmid=2549426 | doi=10.1038/340692a0 | pmc= | url=https://www.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&tool=sumsearch.org/cite&retmode=ref&cmd=prlinks&id=2549426  }} </ref>
 ==References==