Secondary hyperparathyroidism

What it means

Secondary hyperparathyroidism refers to the production of higher than normal levels of parathyroid hormone in the presence of hypocalcemia.

Secondary hyperparathyroidism occurs most commonly secondary to chronic renal failure. Other causes of secondary hyperparathyroidism include osteomalacia, rickets, and malabsorption. The pathophysiology of secondary hyperparathyroidism results from abnormalities in the renal tubular absorption of phosphate with reduced phosphate excretion and hyperphosphatemia, as well as impaired renal conversion of 25-hydroxycholecalciferal to 1,25-dihydroxycholecalciferol, which in turn leads to a decrease in the intestinal absorption of calcium. In combination, elevated serum phosphate levels and reduced vitamin D production result in decreases in serum calcium levels or hypocalcemia, leading to hyperparathyroidism.

Rare diseases that can present with this5

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category