ENDOCRINOLOGY - ACROMEGALY AND GIGANTISM Flashcards
Whats the difference between gigantism and acromegaly?
Gigantism affects kids before epiphyseal plate closes
Acromegaly affects adults
What is gigantism?
A rare hormonal disorder in children where there is excessive growth hormone which leads to rapid and excessive growth of long bones.
What can cause gigantism?
Pituitary adenoma involving mammosomatotroph cells or somatotroph cells - secret excess GH
Hypothalamic tumours
Tumours that produce GH ectopically
What are the symptoms of gigantism?
Height significantly above SD
Obesity
Overgrowth of face and extremities
Maxilla or mandible protrusion
Macrocephaly
Carpal tunnel syndrome and diabetes mellitus (due to diabetogenic efefcts of GH)
decreased menstruation and gynaecomastia.
Headaches and bitemporal hemianopia
What are the complications of gigantism?
Cardiovascular conditions, hypertension in children, osteoarthritis, diabetes mellitus
How is gigantism diagnosed?
Increased levels of insulin like growth factor 1 and GH - particularly if levels are elevated despite recieving a large dose of glucose
Prolactin will be high is mammosomatotroph cells are involves
MRI of pituitary tumour
How is gigantism diagnosed?
Surgery to remove pituitary adenoma or other tumour causing it
Medications - somatostatin analogues or GH receptor antagonists
What is acromegaly?
Hormonal disorder in adults where there is excess GH which causes continued growth of extremities.
What are the causes of acromegaly?
95% are pituitary adenomas of somatotroph cells
Tumours producing GH or GHRH ectopically
What are the sympotms of acromegaly?
Growth of bones, hands, feet and lower jaw
Protrusion of forehead
Soft tissue swelling in hands, feet, face and tongue
Increased size of organs
Excessive sweating (sweat gland hypertrophy), hair growth, skin changes, dental changes
Carpal tunnel syndrome
Galactorrhoea - raised prolactin in 1/3rd of cases
What are the complications of acromegaly?
Hypertension, diabetes, cardiomyopathy, colorectal cancer
How is acromegaly diagnosed?
Serum IGF-1 levels
MRI of pituitary gland
CT scan for ectopic tumours
How is acromegaly treated?
Transphenoidal surgery of pituitary adenoma - first line
Somatostatin analogues (octreotide) or GH receptor antagonists (pegvisomant)
External irradiation is sometimes used for older patients or following failed surgical/medical treatment
