What condition is characterized by excessive levels of parathyroid hormone?

• A. Osteoporosis
• B. Paget's Disease
• C. Hyperparathyroidism
• D. Osteopenia

Answer: (C)

The condition characterized by excessive levels of parathyroid hormone is hyperparathyroidism. This disorder involves the overproduction of parathyroid hormone (PTH) from the parathyroid glands, which are located in the neck. Elevated levels of PTH lead to an increase in calcium levels in the blood, as the hormone stimulates the release of calcium from bones, increases calcium reabsorption in the kidneys, and enhances intestinal absorption of calcium. The result of this excessive hormone production can lead to bone density loss and other complications, including kidney stones and osteoporosis.

Understanding this condition is crucial because it directly relates to how the body regulates calcium and bone health. In hyperparathyroidism, the imbalance created by excessive PTH often results in weakened bones and can be distinguishable through specific symptoms and laboratory tests. This makes hyperparathyroidism a significant area of focus in bone densitometry studies, as it alters bone mineral density and can reflect the need for both diagnosis and management strategies.