Prognosis
If untreated for an extended period, Hashimoto's thyroiditis may lead to muscle failure, including possible heart failure. An extremely rare condition associated with the thyroiditis is Hashimoto's encephalopathy. Although it is well-accepted that Hashimoto's thyroiditis does not cause Hashimoto's encephalopathy, those with Hashimoto's encephalopathy are virtually always eventually diagnosed with Hashimoto's thyroiditis.
A rare association is with lymphoma of the thyroid gland.
Hashimoto's thyroiditis can disrupt growth in children and adolescents and therefore requires close growth monitoring. Growth hormone therapy may be required if the patient's stature is extreme enough.
Read more about this topic: Hashimoto's Thyroiditis