Parathyroid Flashcards
What hormone is produced by the parathyroid gland, and what is its action?
Parathyroid hormone
Rapid and acute regulation of serum calcium
What stimulates release of PTH?
Low serum calcium
What are some actions of PTH?
Increase activity of osteoclasts => increase Ca in ECF
Activated Vit D (1,25-cholecalciferol) in Kidney
What are the actions of vitamin D?
Increase reabsorption of Ca in kidney and gut
What is primary hypercalcaemia?
Increased PTH due to development of an adenoma
Results in hypercalcaemia and hypophosphataemia
What are some symptoms of primary hyperparathyroidism?
Moans - tired, exhaustion, depression
Bones - pain
Stones - kidney stones
Groans - constipation
What is secondary hyperparathyroidism?
Increased PTH due to dietary/environmental deficiency or chronic renal failure
What are the effects of hypercalcaemia?
Increase threshold for action potential => suppression of neuronal activity
Sx:
Lethargy, confusion, coma
What are symptoms of severe hypercalcaemia?
Lethargy Weakness Confusion Coma Renal failure
Requires rehydration
What are the effects of hypocalcaemia?
Lowers threshold for action potential => hyper-excitable nerves
Symptoms:
Tingling, muscles tetany, epilepsy
Carpopedal sign (flexed wrist) Chvostek’s sign
What is osteoporosis?
Decreased bone density with normal mineral:matrix density
Leads to degeneration of already constructed bone => inc risk of fracture
What is osteomalacia?
Decreased mineral:matrix
Not enough mineral in bone
Affects bone building in children (Rickets) and mineralisation in adults
Lead to soft bones which are prone to bending