Autoimmune thyroiditis (Hashimoto's thyroiditis) is chronic inflammation of the thyroid gland, in which the immune system produces antibodies against the gland's own tissue and gradually destroys it.
It is the most common cause of hypothyroidism in iodine-sufficient regions. The disease is more common in women, runs in families and becomes more frequent with age.
Mechanism
The immune system attacks the enzyme thyroid peroxidase and other components of the gland. Anti-TPO antibodies and antibodies to thyroglobulin (anti-Tg) appear in the blood, and the gland's tissue is infiltrated by lymphocytes. Over time there are fewer functioning cells, and hormone production declines.
Course and symptoms
For a long time function is preserved (euthyroidism) and there are no complaints. Then subclinical and later overt hypothyroidism develops, with fatigue, feeling cold, weight gain, dry skin, constipation and low mood. The gland may enlarge (goiter). Early in the disease there is occasionally a brief phase of hormone excess ("Hashitoxicosis").
Diagnosis
The diagnosis rests on a combination of an elevated TSH with a reduced free T4, positive anti-TPO antibodies and a characteristic ultrasound picture. The antibodies may be positive long before function is disturbed.
Treatment
The mere presence of antibodies with normal gland function does not require treatment — only periodic monitoring of TSH is needed. When hypothyroidism develops, levothyroxine is prescribed, its dose adjusted by TSH. There is no specific treatment that "removes" the antibodies; in autoimmune hypothyroidism therapy is usually lifelong.
Calculate using this marker
Calculators where Autoimmune thyroiditis (Hashimoto's) is used directly:
Frequently asked questions
Can Hashimoto's thyroiditis be cured?
The autoimmune process cannot be removed, but its consequence — hypothyroidism — is fully compensated by levothyroxine. As long as gland function is preserved, observation without pills is enough.
Do you have to take pills if anti-TPO is elevated?
No. Positive anti-TPO with normal TSH and free T4 only means an increased risk of hypothyroidism in the future. Treatment is started only when gland function actually declines.