Hyperparathyroidism Flashcards
What is the action of parathyroid hormone?
Increased osteoclast activity
Increases calcium reabsorption in the kidneys
Increases vitamin D activity
What action does vitamin D have on calcium?
Vitamin D increases calcium absorption from the intestines
What is primary hyperparathyroidism?
Uncontrolled parathyroid hormone production by a tumour of the parathyroid hormone glands
What is secondary hyperparathyroidism?
Insufficient vitamin D or chronic kidney disease reduced calcium absorption from the intestines, kidneys and bones.
Low calcium results in the parathyroid secreting more PTH
What is tertiary hyperparathyroidism?
When secondary hyperparathyroidism continues for an extended period, after which the underlying cause is treated (due to hyperplasia of the parathyroid hormone as they adapt to producing a higher baseline of PTH)
What is the treatment of primary hyperparathyroidism?
Removal of the parathyroid gland tumour
What is the treatment of secondary hyperparathyroidism?
Treatment of the underlying cause
What is the treatment of tertiary hyperparathyroidism?
Partial surgical removal of the parathyroid gland
What is calcitonin?
Calcitonin is a hormone secreted by the parafollicular cells of the thyroid
What is the action of calcitonin?
It acts to reduce serum calcium levels
What medication can be used in conservative management of hyperparathyroidism?
Cinacalcet (a calcium mimetic)
What is the action of cinacalcet?
It mimics the action of calcium on tissues - negative feedback on the parathyroid gland results in a decrease in PTH levels, and a decrease in calcium
What blood results would be seen in primary hyperparathyroidism?
Raised calcium
Low phosphate
PTH may be raised or normal
What investigations are used in the diagnosis of hyperparathyroidism?
Serum calcium, phosphate and PTH
Technetium-MIBI substraction scan
X-ray
What blood results would be seen in secondary hyperparathyroidism?
Elevated PTH
Low or normal calcium
Elevated phosphate
