Hyperactivity of anterior pituitary gland:
- Gigantism : it is a rare condition that causes abnormal growth in children.
- Cause : a pituitary tumour is almost always the cause of gigantism. Gigantism is due to hypersecretion of GH in childhood or in the preadult life before the fusion of epiphysis of bone with shaft.
- Other less common causes of gigantism include McCune-Albright syndrome causes abnormal growth in bone tissues, patches of light brown skin, and gland abnormalities
- Carney complex is an inherited condition that causes non cancerous tumours on connective tissue, cancerous or non cancerous endocrine tumours
- Signs of gigantism – very large hands and feet, thick toes and fingers, a prominent jaw and forehead, coarse facial features, excessive sweating, insomnia, delayed puberty, deafness
- Treatment – surgery (removing the tumour), bromocriptine and cabergoline are drugs that can be used to lower growth hormones, Gamma knife radiosurgery
- Acromegaly : it is the disorder characterized by enlargement, thickening and broadening of bones.
- Cause : acromegaly is due to hypersecretion of GH in adults after the fusion of epiphysis with the shaft of the bone and a benign tumour affecting the pituitary called adenoma
- Signs : vision loss, protrusion of supra orbital ridges, broadening of nose, thickening of lips, prognathism, carpal tunnel syndrome, uterine fibroids in women, arthritis, sleep apnea
- Treatment : surgery, medication – somatostatin analogs, GH receptor antagonists, dopamine agonists, radiation
- Acromegalic Gigantism: it is a rare condition with symptoms of both acromegaly and gigantism.
- Cushing’s disease : it is a hormonal disorder caused by high levels of the hormone cortisol in your body. It’s also known as hypercortisolism.
- Causes : most common cause is related to medications called glucocorticoids, one can also get the disease from injectable steroids, such as repeated shots for joint pain, bursitis, back pain
- Symptoms – buffalo hump, rounded and rosy face, thinning skin, acne, being very tired, kidney stones, sleep problems
- Treatment : surgery, hormone replacement medications, life style changes
Hypoactivity of anterior pituitary gland:
- Dwarfism : it is a pituitary disorder in children characterized by stunted growth
- Causes : reduction of GH secretion in infancy or early childhood due to deficiency of GHRH from hypothalamus or somatomedin C, atrophy or degeneration of acidophilic cells in the anterior pituitary, achondroplasia
- Signs : stunted skeletal growth, head becomes slightly larger in relation to the body, reproductive function is not affected, mental activity is normal
- treatment : corrective surgeries, surgery to widen spinal cord, extended limb lengthening
- Acromicria : it is characterized by the atrophy of the extremities of the body
- Causes : deficiency of GH releasing hormone from hypothalamus, tumour of chromophobes, panhypopituitarism (reduction in secretion of all hormones of anterior pituitary gland)
- Signs : atrophy and thinning of extremities of body, hypothyroidism, person becomes lethargic and obese
- Simmonds’ disease : it is also called pituitary cachexia
- Cause : occurs mostly in panhypopituitarism
- Symptoms : rapidly developing senile decay, loss of hair over body and loss of teeth, skin on face becomes dry and wrinkled
Hyperactivity of posterior pituitary gland:
- Syndrome of inappropriate hypersecretion of antidiuretic hormone : it is characterized by loss of sodium through urine duebto hypersecretion of ADH
- Cause : due to cerebral tumours, lung tumours and lung cancers
- Signs and symptoms : loss of appetite, weight loss, nausea and vomiting, headache, muscle weakness, spasm, cramps
Hypoactivity of posterior pituitary gland:
- Diabetes inspidus : it is characterized by excess excretion of water through urine
- Cause : deficiency of ADH which occurs due to lesion or degeneration of supra optic and paraventricular nuclei of hypothalamus, atrophy of posterior pituitary
- Signs : polyuria, polydypsia (intake of excess water) and dehydration
- Medication – desmopressin
Source : essentials of physiology by sembulingam