What is subacute thyroiditis?
Much less common than Hashimoto's disease, subacute thyroiditis is a painful inflammation that develops suddenly in a patient who has had a viral infection, such as mumps or an upper respiratory illness. Pain radiates throughout the neck and
patients feel ill and feverish. It may take as long as several months for normal thyroid function to resume.
In this the thyroid enlarges fairly rapidly and can be very painful and tender to feel. The patient can develop a fever, feel ill, lose appetite and may have difficulty swallowing. In about half the patients there is an initial thyroid overactivity due to discharge of stored thyroid hormone from the thyroid gland caused by the inflammation. However unlike classical thyrotoxicosis (called Graves disease) the uptake of iodine on scanning is very low or non existant. Thyroid antibodies are not present to any significant degree.This early thyrotoxic state soon ends after several weeks and the patient’s thyroid hormones in the blood return to normal. Some patient’s however can become transiently hypothyroid but a full recovery is usual over a period of weeks or months. Regrettably there are some patients who require long term thyroid hormone replacement for the thyroid does not recover sufficiently. Recurrences are uncommon.
As this is a short term disease the initial thyrotoxicosis is treated differently from Graves disease usually with b blockers such as propanolol or nadolol. Pain treatment may be required, some find help with aspirin and in severe cases pain relief is achieved with steroids (prednisolone).
The main symptoms are a painful swelling of the thyroid gland and symptoms of hyperthyroidism. These symptoms include heat intolerance, nervousness, palpitations and weakness. The hyperthyroidism is due to the leaking of thyroid hormones from the damaged thyroid cells as a result of the viral infection. This is a temporary situation since once the virus infection has run its course, the thyroid cells recover their normal state. On examination, the patient has a very tender, swollen thyroid gland and mild signs of hyperthyroidism. Most people recover completely from this type of thyroiditis. Generally the thyroiditis resolves by itself within a few months, but sometimes it comes back or, more rarely, damages enough of the thyroid gland to cause permanent hypothyroidism.
The treatment for milder forms of this condition is aspirin, given for the inflammation, swelling and pain. Patients with severe symptoms may be given steroids (cortisone). In most cases, the patient recovers within a few days. In a few people, the illness lasts longer and in some it recurs. In almost one-quarter of patients, a temporary phase of hypothyroidism, which may require treatment with thyroxine, occurs as a result of the severe damage to the thyroid cells. Eventually, the cells recover and the thyroxine treatment can cease. |
