Acromegaly and gigantism are chronic metabolic disorders caused by excessive growth hormone levels. Acromegaly occurs in adulthood after bone growth plates have closed, causing tissue enlargement. Gigantism occurs in childhood before plate closure, resulting in abnormally large growth. Both are usually due to noncancerous pituitary tumors that overproduce growth hormone, leading to increased insulin-like growth factor levels and symptoms like enlarged hands, feet and head. Diagnosis involves blood tests and imaging to identify the source of excess growth hormone. Treatment focuses on surgery, radiation or medications to reduce hormone levels and stop further growth.

1. ACROMEGALY
&
GIGANTISM
BY : RITWAN BIN TAPENG

2. A
C DEFINITION
R
O Chronic metabolic disorder in which there is
M too much growth hormone and the body
E
tissue gradually enlarge
G
A
L
Y

4. PATHOPHYSIOLOGY
Acromegaly is characterized by hypersecretion of growth hormone (GH),
which is caused by the existence of a secreting pituitary tumor in more than
95% of acromegaly cases. Pituitary tumors are benign adenomas and can be
classified according to size (microadenomas being less than 10 mm in
diameter and macroadenomas being greater than 10 mm in diameter).3,4 In
rare instances, elevated GH levels are caused by extra pituitary disorders. In
either situation, hypersecretion of GH in turn causes subsequent hepatic
stimulation of insulin-like growth factor-1 (IGF-1).1

5. SYMPTOMS
 Body odor
 Carpal tunnel syndrome
 Decrease muscle strength ( weakness )
 Easy fatique
 Enlarge feet
 Enlarge hands
 Enlarge glands in the skin ( sebaceous glands )
 Enlarge jaw and tongue
 Excessive height
 Excessive sweating

6. SYMPTOMS ( cont… )
 Headdache
 Hoarseness
 Joint pain
 Limited joint movement
 Sleep apnea
 Swelling of bony areas around a joint
 Thickening of skin, skin tags
 Widely spaced teeth
 Excess hair growth in females
 Weight gain

7. DIFFERENTIAL DIAGNOSIS
 Pseudoacromegaly
 Presence of similar acromegaloid features in the absence of elevated GH or IGF-I
levels
 Physiologic growth spurt during puberty
 Familial tall stature or large hands and feet
 Myxedema

8. INVESTIGATION
 Visual field tests
 Assessment of other pituitary hormones: prolactin, adrenal, thyroid, and
gonadal hormones
 MRI scan of pituitary and hypothalamus: more sensitive than CT scan
 CT scan: for lung, pancreatic, adrenal or ovarian tumours that may secrete
ectopic growth hormone or GHRH
 Total body scintigraphy with radio-labelled OctreoScan® (somatostatin) to aid
localisation of the tumour
 Cardiac assessment: electrocardiogram, echocardiogram

9. PROGNOSIS
 Pituitary surgery is successful in most patient, depending on the size of the
tumor and the experience of the surgeon
 Without treatment the symptoms will get worse,and the risk of cardiovascular
disease increase

10. COMPLICATIONS
 Arthritis
 Cardiovacular disease
 Carpal tunnel syndrome
 Colonic polyps
 Glucose intolerance or diabetes
 High blood pressure
 Sleep apnea
 Spinal cord compression
 Uterine fibroids
 Vision abnormalities

11. REFERENCES
 http://onlinelibrary.wiley.co
 http://www.harrisonspractice.com/practice/ub/view/Harrisons%20Practice/1
41312/2.0/acromegaly
 http://www.patient.co.uk/doctor/Acromegaly.htm
 http://www.acromegalyinfo.com/health-care-professional/epidemiology-
pathophysiology.jsp

12. G
I
DEFINITION
G Abnormally large growth due to an excess of
A growth hormone during childhood, before the
N bone growth plates have closed.
T
I
S
M

14. CAUSES
The most common cause of too much growth hormone release is a noncancerous
(benign) tumor of the pituitary gland. Other causes include:
 Carney complex
 McCune-Albright syndrome (MAS)
 Multiple endocrine neoplasia type 1 (MEN-1)
 Neurofibromatosis
If excess growth hormone occurs after normal bone growth has stopped, the
condition is known as acromegaly.

15. SYMPTOMS
 Delayed puberty
 Double vision or difficulty with side (peripheral) vision
 Frontal bossing and a prominent jaw
 Headache
 Increased sweating
 Irregular periods (menstruation)
 Large hands and feet with thick fingers and toes
 Release of breast milk
 Thickening of the facial features
 Weakness

16. EXAMS & TESTS
 CT or MRI scan of the head showing pituitary tumor
 Failure to suppress serum growth hormone (GH) levels after an oral glucose
challenge (maximum 75g)
 High prolactin levels
 Increased insulin growth factor-I (IGF-I) levels
Damage to the pituitary may lead to low levels of other hormones, including:
 Cortisol
 Estradiol (girls)
 Testosterone (boys)
 Thyroid hormone

17. TREATMENT
Medical treatments of gigantism
 Medications may be used to reduce GH release, block the effects of GH, or prevent
growth in stature. They include:
 Dopamine agonists, such as bromocriptine mesylate (Cycloset, Parlodel) and cabergoline
(Dostinex), which reduce GH release
 GH antagonist, pegvisomant (Somavert), which blocks the effects of GH
 Sex hormone therapy, such as estrogen and testosterone, which may inhibit the growth of
long bones
 Somatostatin analogs, such as octreotide (Sandostatin) and long-acting lanreotide
(Somatuline Depot), which reduce GH release

18. TREATMENT ( cont… )
Other treatments of gigantism
 Radiation of the pituitary gland to regulate GH. This is generally
considered the least desirable treatment option because of its limited
effectiveness and side effects that can include obesity, emotional
impairment, and learning disabilities
 Surgery to remove a pituitary tumor, which is the treatment of choice
for well-defined pituitary tumors

19. PROGNOSIS
Pituitary surgery is usually successful in limiting growth
hormone production.

20. COMPLICATIONS
 Delayed puberty
 Difficulty functioning in everyday life due to large size and unusual features
 Diminished vision or total vision loss
 Embarrassment, isolation, difficulties with relationships, and other social
problems
 Hypothyroidism
 Severe chronic headaches
 Sleep apnea

21. REFERENCES
 http://health.nytimes.com/health/guides/disease/gigantism/overview.html
 http://www.localhealth.com/article/gigantism/treatments
 http://emedicine.medscape.com/article/925446-overview
 http://www.scientificamerican.com/article.cfm?id=what-causes-gigantism-
sandy-allen
 http://www.yourhormones.info/endocrine_conditions/gigantism.aspx