Hypopituitarism is characterised by reduced secretion of anterior pituitary hormones. Panhypopituitarism is a deficiency of all anterior hormones. It is commonly caused by surgery, a pituitary tumour, and radiation. Hormones are affected in this order: Growth hormone (GH) → Luteinizing…
Hypopituitary coma is a decompensation of chronic hypophyseal failure that is characterised by hypothermia, refractory hypotension, and signs of hypopituitarism.
Hypercortisolism is caused by excessive glucocorticoids. Definition of terms Term Definition Cushing’s syndrome The clinical state that is produced by chronic glucocorticoid excess, loss of the hypothalamo-pituitary-adrenal axis, and loss of circadian rhythm of cortisol secretion. Exogenous hypercortisolism Hypercortisolism caused…
Adrenal insufficiency is caused by the underproduction of adrenocortical hormones. Definition of terms Term Definition Primary adrenal insufficiency (Addison’s disease) This is primary adrenal insufficiency. Although rare, it can be fatal since destruction of the adrenal cortex leads to glucocorticoid…
Adrenal crisis is an acute life-threatening condition characterised by severe hypotension, hypoglycaemia, and altered mental status. It can occur in patients with known Addison’s disease when oral steroids are not increased to cover stress or when dosages have been missed.…
Hyperparathyroidsim Hyperparathyroidism refers to excess secretion of parathyroid hormone. Primary Hyperparathyroidism Primary hyperparathyroidism is caused by the excess secretion of parathyroid hormone (PTH), resulting in hypercalcemia. 85% of cases are due to a parathyroid adenoma. It peaks at 70+ years…
Hypoparathyroidism is caused by deficient or absent parathyroid hormone production. This results in hypocalcemia and hyperphosphatemia. Definition of terms Term Definition Primary hypoparathyroidIsm Reduced PTH secretion due to gland failure Secondary hypoparathyroidism Reduced PTH secretion secondary to radiation, thyroidectomy, parathyroidectomy,…
Primary Hyperaldosteronism (Conn’s Syndrome) Primary hyperaldosteronism is characterised by autonomous excessive secretion of aldosterone by an adrenal adenoma or bilateral adrenal hyperplasia. It commonly presents with resistant hypertension and hypokalemia. Secondary Hyperaldosteronism Secondary hyperaldosteronism is caused by excessive renal production…
Phaeochromocytoma is a neuroendocrine tumour that arises from chromaffin cells of the adrenal medulla. It is characterised by excessive catecholamine production, which causes the clinical triad of headache, diaphoresis, and tachycardia. 10% occur in children, 10% are bilateral, 10% are…
The overproduction of prolactin causes hyperprolactinaemia. It is the most common hormonal disturbance of the pituitary gland. It is present early in women due to menstrual disturbance. Prolactin levels > 5000 are likely to be due to a prolactinoma. Macroadenomas (>…