Why some persons are giant like

Gigantism and Acromegaly

Keywords: IGF-1 levels, gigantism, acromegaly level of IGF-1.

Table of contents:

1.	Introduction
2.	Incidence
3.	Features of Acromegaly Gigantism
4.	Causes
5.	Diagnosis
6.	Complications
7.	Treatment

Introduction :Abnormal excess secretion, i.e.hypersecretion of growth hormone, causes gigantism and acromegaly.

When hypersecretion of growth hormone occurs before the fusion of the long bones epiphysis leading to tall stature, hypersecretion of growth hormone causes increases in the size of bones.  Therefore, before puberty, the growth hormone increases the length of bones leading to increased height and is called gigantism.

Acromegaly: hypersecretion of growth hormone after the fusion of the long bones epiphysis, i.e., after puberty, increases bone size, especially bones of hands, feet, and face.  The condition is known as acromegaly.

Incidence :  is very low only 0.001%.  10 new cases/1000,000 population.

Male and females are equally affected.

Usually appears in 5^th decade of life.

Etilogy of Gigantism and acromegaly

Some genetic syndromes like neurofibromatosis, Carney complex, McCune-Albright syndrome, and Multiple endocrine neoplasias are associated with hypersecretion of the growth hormone.             

1.  Adenoma in the anterior pituitary gland is responsible for more than 95% of cases.  In addition, familial idiopathic pituitary adenoma is responsible in some cases.

2.  Excess secretion of ‘growth hormone-releasing hormone from a hypothalamic adenoma,

3.  In some cases, neuroendocrine tumors from the lungs or pancreas secrete growth hormone-releasing hormone causing hypersecretion of Growth hormone.

4.  In some cases, abdominal and other tumors can secrete ‘growth hormone-releasing, hormone causing hypersecretion of the growth hormone.

Features of acromegaly:

Acromegaly develops very slowly.

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1.  Enlargement of hands and feet due to bone thickness and soft tissue swelling.  Bony changes are permanent.  The extremities have a ‘dough-like consistency.

2.  Increased sweating-hyperhidrosis.

3.  Weakness, lethargy, kyphoscoliosis.

4.  Acromegaly facies are characteristic of acromegaly.  The features of acromegaly facies are a broad nose, large lips, enlarged tongue, coarsening of face, prominent supraorbital ridges, and enlarged jaw.

5.  Deep voice

6.  Obstructive sleep apnea.

Gigantism

Gigantism is a rare condition suspected when there is a rapid increase in the length of a person.  Gigantism is usually associated with other syndromes, so features are multiple.

Diagnosis

1.  EstimationofIGF-1 level is used to diagnose.

2.  EstimationofGH levels is used to diagnose.

3.  MRI and CT

3.  Prolactin estimation.

4.  Estimation of levelsof hormones of the anterior pituitary.

Treatment

Aims of management of acromegaly/ gigantism are

1.  Remove tumors secreting Growth hormones and ‘growth hormone- releasing hormone’-if possible.

2.  Radiation therapy if removal of adenoma is not possible.

3.  Medical therapy is available-

      Dopamine agonists-cabergoline is a D2 receptor agonist that acts on the D2 receptors in somatotrophs and decreases GH secretion.

       GH receptor antagonists.

Complications

1.  Cardiomyopathy

2.  Hypertension

3.  Arthropathy

4.  Obstructive Sleep Apnea.

Hypopituitarism may occur due to surgery or radiation.  Therefore, assessing hormones of anterior pituitary levels and hormone replacement may be needed.

Tags:  Causes of acromegaly and gigantism #diagnosis #management#Hormones responsible for acromegaly#

Internal Link: http://blog.totalphysiology/2022/04/growthhormone-gigantism acromegaly.html.

External Link:    https://www.ncbi.nim.nih.gov>books/NBK538261/