Final answer:
Hypoparathyroidism is caused by sudden reduction of parathyroid hormone, leading to hypocalcemia and symptoms such as tetany. It is often a result of accidental removal or damage to the parathyroid glands during surgery or due to autoimmune issues.
Step-by-step explanation:
The condition described in the question is hypoparathyroidism, which is caused by the sudden withdrawal of parathyroid hormone in patients with severe hyperparathyroidism. This leads to an increased influx of calcium from circulation into bone. Normally, parathyroid hormone (PTH) regulates calcium levels within the blood by stimulating bone resorption to release calcium, reabsorption of calcium in the kidneys, and activating vitamin D to increase calcium absorption in the gut. However, when there is an underproduction of PTH, it results in abnormally low blood calcium, or hypocalcemia, which can cause severe muscle contractions known as tetany.
Various factors can cause hypoparathyroidism, including accidental removal of the parathyroid glands during thyroid surgery, or autoimmune destruction of the glands. Without adequate PTH, calcium is not efficiently mobilized from the bone, leading to the symptoms associated with this condition.