- excessive PTH secreted by parathyroid glads in response to hypocalcemia.
- Seen in chronic renal failure (most common cause of secondary HPT)
- Bone and joint pain are common
- Parathyroid hypertrophy
- no role for parathyroid surgery
- Vitamin D deficiency can cause secondary HPT
Normal calcium level with elevated PTH
Normal calcium blood levels with an elevated PTH might be due to vitamin D levels. Low vitamin D levels lead to elevated PTH levels to help maintain normal calcium blood levels.
Chronic Renal Failure
- Failing kidneys fail to convert enough vitamin D to its active form
- Does not adequately excrete phosphate into the urine
- Insoluble calcium phosphate forms in the body which removes calcium from the circulation – thus hypocalcemia and thus increases parathyroid hormone in an attempt to increase serum calcium levels
Other causes besides renal failure
- Malabsorption dependent bariatric surgery
- malabsorption due to chronic pancreatitis, small bowel disease
What is tertiary hyperparathyroidism?
Tertiary hyperparathyroidism occurs when the correction of the underlying cause will not stop excess PTH secretion
Vitamin D and Calcium?
The body needs vitamin D to absorb calcium from our diet.
What is primary hyperparathyroidism?
- Increased PTH secretion and raised serum calcium levels
- 85% caused by parathyroid adenoma (usually only one gland affected)
- 10% caused by chief cell hyperplasia
What is hungry bone syndrome?
- Severe Hypocalcemia seen after surgical correction of HPT
- Chronically deprived bone aggressively absorbs calcium
What is subclinical cushing’s syndrome?
- subclinical hypercortisolism / may be observed with adrenal incidentaloma
- autonomous clucocorticoid production without specific signs and symptoms of Cushing’s syndrome.
- Much more common than classic Cushing’s syndrome
- Patients have a high prevalence of obesity, hypertension, and type 2 diabetes.
- Patients with incidentally detected adrenal masses who are about to undergo surgery should have testing for subclinical Cushing’s to avoid postoperative adrenal crisis..
- Best test is short dexamethasone suppression test.
What is Cushing’s syndrome?
- exaggerated facial roundness,
- weight gain around the midsection and upper back
- thinning of arms and legs.
- stretch marks
- Cushing’s syndrome occurs when exposed to high levels of the hormone cortisol for an extended period of time.
- this can either occur with taking too much corticosteroid medication or when the body makes too much cortisol.
- Pituitary adenoma – secreting excess ACTH which stimulates the adrenal glands to make more cortisol
- Ectopic ACTH secreting tumor (ie. Lungs, pancreas, thyroid or thymus gland)
- Primary Adrenal Gland disease
- Familial Cushing syndrome
Diabetes type 1 vs. type 2
Type 1 = immune disorder. Body attacks and destroys insulin producing beta cells in the pancreas. Must take insulin. Sometimes called insulin dependent or juvenile onset diabetes.
Type 2 = either the body doesn’t produce enough insulin or the cells ignore the insulin (resistant). Sometimes called adult onset diabetes. Obesity is the strongest risk factor for type 2 diabetes.
Adrenalectomy for subclinical Cushing’s Syndrome?
Adrenalectomy may lead to cure or better control of diseases associated with subclinical Cushing’s syndrome such as diabetes and hypertension
Most pose no clinical problems.
Low Calcium after thyroidectomy
- Most common complication after total or near total thyroidectomy is hypocalcemia due to hypoparathyroidism. Post thyroidectomy hypoparathyroidism is usually related to disruption of the blood supply to parathyroid glands.
- A patient needs only a single healthy parathyroid gland to have normal parathyroid function.
Symptoms of hypocalcemia
- Could be asymptomatic or show up as:
- mild paresthesias
- Painful tentany
- muscle aches
- weakness or twitching
- Larngeal spasm
- Parathyroid hormone measurement after surgery. Possibly consider this protocol. If less than 10 (pg/ML) supplement with calcium and calcitriol. If between 10-20 supplement with calcium. If greater than 20 – then no supplementation.
- PTH is secreted by the chief cells of the parathyroid gland.
- Acts to increase the concentration of calcium in the blood
- PTH half life is about 4 minutes.
what is Calcitriol?
- Hormonally active form of vitamin D.
- After thyroidectomy, supplimentation with Calcitriol may supress PTH levels.
A main reason for hospitalization overnight after total thyroidectomy
To monitor for the risk of hypocalcemia.