Ask Dr. H: Embryonic duct can cause problems

Question:

Can you explain what a "thyroglossal duct cyst" is?

Answer:

During the normal development of an embryo, the thyroid gland begins to form at the base of the tongue and migrates down the neck to its final position via the "thyroglossal duct." This duct is normally supposed to disappear by birth, but in some folks it persists.

The persistence of this connection between the tongue and the thyroid gland in the neck may lead to the formation of cysts (pockets) within the duct. The duct can fill with mucus and other secretions from the tongue and is prone to infection.

They're usually diagnosed in childhood when a neck mass appears - sometimes tender from infection and sometimes painless. It may cause difficulty swallowing or breathing if it becomes large enough.

Since the duct is attached to the base of the tongue, it'll move when swallowing or sticking out the tongue.

Treatment for a thyroglossal duct cyst that's causing pain or discomfort (or is just cosmetically unattractive) usually involves surgical removal and antibiotics to treat any infection.

Thyroid function studies, thyroid ultrasound and thyroid scanning are usually performed before planned surgery.

Q:

What causes us to shiver and sweat when we've got a fever?

A:

Fever, uncomfortable though it may be, is a good thing.

It helps increase the chances of surviving an infection that would otherwise have led to death in the days before antibiotics. Fever has been shown in animal studies to rev up the body's ability to fight off infections and even some forms of cancer. It also helps to inhibit bacterial and viral activity. Fever also lets us know that we're not well. It tries to slow us down so we rest.

When we have a fever, the bacteria or virus becomes engulfed by our infection-fighting white blood cells, triggering those cells to release fever-causing substances known as "pyrogens."

Pyrogens act on the hypothalamus, the part of the brain that regulates our body's temperature. When the "thermostat" is turned up by the effect of pyrogens, the body tries to maintain a higher temperature by decreasing sweating and increasing body movement through the shivers and chills. If at the higher body temperature the pyrogens are broken down, the hypothalamus resets to its usual lower body temperature and heat-loss mechanisms like profuse sweating try to cool us down.

While fever has an important role in getting us well, the fever effects like dehydration and shaking chills make us awfully uncomfortable. That's why Tylenol, Advil, Aleve or aspirin, in addition to drinking lots of fluids like Gatorade/Powerade or diluted orange juice, is so helpful.