Correlation 13: Parathyroid hyperplasia

The normal parathyroid has a mixture of fat cells and parathyroid tissue, mainly chief cells, but here there are only a few fat cells. Note the nodule of pink oxyphil cells in the center.

An increase in the number of cells in an organ is known as hyperplasia. When this happens to the parathyroid glands (of which there are typically four) then the condition is known as parathyroid hyperplasia. The chief cells of the parathyroid produce parathormone, which is a hormone that increases the amount of calcium in the blood. Hyperplastic glands are producing too much hormone. This is detected by measuring the calcium in the blood or the amount of parathyroid hormone.