What is Acromegaly ?
(acral = distal, megaly = enlargement)
Acromegaly is a chronic disease of middle age characterized by organomegaly, hypertrophy of tissues and altered metabolism in response to prolonged and excessive secretion of growth hormone.
Hyperpitutarism is the excessive secretion of the pituitary hormones. Hyperpitutarism results in a disease called acromegaly.
What causes Acromegaly ?
Acromegaly may occur due to
A. Primary Disease of the Pituitary Gland (99%)
- Pituitary tumor
- Pituitary hyperplasia
B. Secondary Disease due to Excessive Stimulation by an Ectopic GH or GRH Secreting Tumor: (very rare, < 1%)
These tumors could be carcinoid of the bronchus and foregut, pancreatic islet tumor and small cell carcinoma of the lung.
In patients with ectopic Growth hormone Releasing factor (GRF), the immunoreactive plasma GRF levels are readily detectable in contrast to patients having primary pituitary disease in whom, these levels are almost undetectable.
What are the effects of Acromegaly ?
I. Due to Increased Intra-sellar Tension: Headache, vomiting, papilledema.
II. Due to Compression of Neighboring Structures. (Parasellar manifestations):
- Bitemporal hemianopaia (optic chiasma)
- Blindness due to optic atrophy (optic nerves)
- Ophthalmoplegia (Paralysis of III, IV and VI nerves)
- Deafness (Paralysis of VIII nerve.)
- Cerebral symptoms: hemiparesis, mental changes and uncinate fits.
- Hypothalamus: Disturbances of sleep, temperature control, appetite and autonomic function.
III. Due to Growth Hormone Excess
A. Skeletal changes:
- Enlargement of hands and feet (Spade-like) and tufting of terminal phalanges on X-rays.
- Enlargement of facial bones and prognathism (lantern jaw). Lower incisors may protrude in front of the upper incisors by more than half an inch. The teeth may be spaced apart.
- Enlargement of frontal, mastoid and ethmoid sinuses. The calvarium is thickened on X-rays.
- Thickening of the clavicles.
- Spine: Kyphoscoliosis, lordosis and osteoporosis.
B. Soft tissues:
- Enlargement of tongue, thickening of lips, nose (Fig. 3.1) and soft tissues of hand and feet. . Thus increasing ring size, chappal and shoe size.
- Skin: Coarse and greasy; hypertrichosis; acanthosis nigricans and fibroma molluscum occurs. Increased sweating is a sensitive biological indicator of disease activity.
- Mammary hyperplasia.
C. Visceral: Splanchnomegaly.
- Heart: Cardiac enlargement (Cardiomyopathy), hypertension and cardiac failure.
- Lungs: Decreased vital capacity due to kyphoscoliosis and enlargement lungs.
- Larynx: Enlargement of larynx (vocal cords) results in a deep voice.
- Diabetes mellitus
- Weight gain
- Impaired memory and depression
- Myopathy and entrapment neuropathy
IV. Disturbances of Other Hormones:
- Galactorrhoea (? Prolactin excess)
- Amenorrhoea in females and decreased libido in males.
This was in detail about what is acromegaly and what causes acromegaly and what are the effects of acromegaly. If You have any other question regarding your heal feel free to Ask a Doctor.