thyroiditis
Meaning of thyroiditis: One name covering several unrelated illnesses, united only by an inflamed thyroid and by hormone levels that often swing before settling.
Definition of thyroiditis
Thyroiditis is inflammation of the thyroid, the butterfly-shaped gland in the front of the neck that sets the pace of the body's chemistry. Several distinct conditions share the name, ranging from a painless autoimmune attack that unfolds over years to a painful swelling after a viral illness. The inflammation can leave hormone output high, low, or eventually normal.
How thyroiditis is built
- thyr/o, thyroid/o Combining form · Greek thyroid gland
- -itis Suffix · Greek inflammation
A medical term is read from its ending backwards: the suffix first, then the prefix, then the root. See all 223 word parts.
What does the name cover?
Inflammation here is usually not an infection. In most forms the immune system attacks the gland's own cells, and the varieties differ in how fast that happens, whether it hurts, and whether the gland recovers. Grouping them under one word is a description of what the tissue looks like, not a diagnosis in itself, which is why the type is almost always named alongside it.
| Type | Course |
|---|---|
| Hashimoto | Painless autoimmune damage over years, ending in low hormone output |
| Subacute | Painful gland after a viral illness, usually settling over months |
| Postpartum | Follows birth, often overactive then underactive, frequently temporary |
| Silent | Painless and self-limiting, the same pattern without pregnancy |
| Suppurative | Rare bacterial infection of the gland, with fever and a tender neck |
| Drug related | Triggered by certain medicines, including some cancer immunotherapies |
Why do hormone levels swing?
The gland stores weeks of finished hormone. When inflammation damages the cells holding that store, it leaks into the blood at once, so the first phase of several types is an overactive one: racing heart, weight loss, tremor. The store then runs out and the damaged gland cannot refill it, so an underactive phase follows. In many people the gland recovers and levels return to normal, while in Hashimoto thyroiditis the loss is permanent and hypothyroidism is the end point.
How is it recognized?
Blood tests come first. Thyroid stimulating hormone rises when the gland is failing and falls when hormone is spilling out, so a single reading identifies which phase is present but not which type. Antibodies against thyroid proteins point to the autoimmune forms. Pain, or its absence, separates the subacute form from the rest. Scanning shows whether the gland is taking up iodine, which distinguishes a leaking gland from one that is genuinely overworking.
Also known as
Used in a sentence
Postpartum thyroiditis was considered given the timing of the symptoms.
Good to know
An overactive phase early in several forms reflects stored hormone leaking from damaged tissue rather than a gland working harder, which is why iodine uptake is low at a point when hormone levels are high.
Word origin
Where “thyroiditis” comes from
Built from the Greek thyreoeides, meaning shield-shaped, describing the large cartilage in front of the gland, with -itis, the ending used for inflammation.