Hypocalcaemia

Hypocalcaemia is characterised by a decreased level of calcium in the bloodstream. It is commonly caused by hypoparathyroidism or vitamin D deficiency. Acute hypocalcemia is a medical emergency that requires prompt correction with intravenous calcium gluconate. Causes of hypocalcaemia Category…

Hypopituitarism

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…

Adrenal insufficiency

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…

Hyperparathyroidism

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

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,…

Hyperaldosteronism

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…

Pheochromocytoma

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…