Parathyroid cyst

What is a parathyroid cyst?

A parathyroid cyst is a condition in which a fluid filled sac develops in the parathyroid glands. There are two types of parathyroid cysts: functional and nonfunctional. Whereas nonfunctional parathyroid cysts do not result in increased levels of parathyroid hormone, functional parathyroid cysts cause excessive secretion of parathyroid hormone. These two types of cysts have different mechanisms of development and require different kinds of treatments.

Nonfunctional parathyroid cyst

In human embryos, the pharyngeal pouches (which correspond to gills in fish) descend to location on the rear of the thyroid gland. There they form the parathyroid glands. Nonfunctional parathyroid cysts are thought to develop from tubes that are left when the pharyngeal pouches descend.

Functional parathyroid cyst

The origin of functional parathyroid cysts is thought to be the cystic degeneration of parathyroid adenoma.

Symptoms

Nonfunctional parathyroid cyst

There tends to be no symptoms.

Functional parathyroid cysts

Symptoms are the same as those caused by primary hyperparathyroidism.

Tests and treatment

Blood tests for calcium and parathyroid hormone levels are performed to determine whether the parathyroid cysts are nonfunctional or functional. The location of cysts is determined by ultrasonography (echography), computed tomography (CT), and isotope examination (methoxy-isobutyl-isonitrile [MIBI] scintigraphy).

Nonfunctional parathyroid cysts

The primary treatment is therapeutic fine-needle aspiration, which drains the cyst of fluid. In some cases, patients may receive percutaneous ethanol injection therapy (PEIT).

Functional parathyroid cysts

Treatment approaches depend on numerous factors, including blood calcium levels, bone density, and history of kidney stones. Patients may either undergo surgery or opt for a wait-and-see approach that involves regular monitoring. Surgery is the most common form of treatment since functional parathyroid cysts may recur even after other types of treatment are initially successful.

Daily life

There are no particular restrictions for daily life, but patients should undergo regular testing and examinations.