This sqadia.com video lecture provides an in-depth elucidation of the parathyroid gland disorders. This lecture has been delivered by our medical specialist, Dr Ammar Hassan. He has explained about the normal physiology of parathyroid gland in human body and has also shed light upon an important clinical condition entitled hyperparathyroidism. In addition to that, the three classes of this malady have also been expansively described. These include the primary, secondary and tertiary types which can be distinctly diagnosed and present with certain clinical features.
Parathyroid and Hypoparathyroidism
First section of this medical lecture emphasizes on the parathyroid and hyperparathyroidism. Parathyroid gland, located behind the thyroid gland, plays a significant role in normal human physiology. It regulates the calcium levels in the blood stream via a hormone called parathyroid hormone (PTH). The concentration of blood calcium and the secretion of parathyroid hormone (PTH) are antagonist to each other. Hypoparathyroidism is a medical condition which is characterized by tetany, Chvostek and Trousseau sign and prolonged QT interval. On the other hand, pseudohypoparathyroidism type 1A is caused by a defective gene guanine-nucleotide binding protein (GNAS). It causes organ resistance along with calcification and short metacarpal and metatarsal bones.
In the following section, Dr Ammar has comprehensively explained about primary hyperthyroidism. This disorder is the malfunctioning of one or more parathyroid glands. As is indicated by its name, this ailment is owing to the hyperfunctioning of the parathyroid cells due to hyperplasia, adenoma or carcinoma. Generally, hyperparathyroidism has been categorized as primary, secondary and tertiary types. The primary and tertiary types have high serum calcium levels whereas, the secondary type has low/normal levels. The primary category can be caused either due to pathological or clinical conditions related to familial/isolated PHTP. Each class can be diagnosed distinctly by the measurement of serum calcium and PTH levels.
This medical ailment is marked by the excessive release of PTH in response to hypocalcaemia. Various factors contribute towards the development of this condition. These include low calcitriol levels, skeletal resistance and altered parathyroid gland growth and functioning alongside the reduced renal mass. The outcome of gland hyperplasia can be in the form of any other disease manifestation. These can be osteomalacia, osteosclerosis, osteoporosis or adynamic bone disease. These present with distinct radiological signs such as pseudofractures, rugger jersey spine or pepperpot skull.
This defect usually presents after a prolonged secondary type. In this anomaly, there is enhanced synthesis of PTH, and the parathyroid gland is enlarged. The levels of PTH remain elevated even if hypocalcaemia is corrected. It has its own clinical manifestations viz epulis, muscular atrophy, nephrocalcinosis, adenoma and many more. In this type of hyperparathyroidism, calcium and phosphate levels are high whereas, PTH levels are very high. On the contrary, in the primary type levels of all three indicators are high but in case of secondary, only PTH is raised.