Category Archives: Hypocalcemia

Secondary HPT

Secondary Hyperparathyroidism

  • 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

Post operative hypocalcemia

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
  • Arrythmia

PTH

  • 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.