Silent thyroiditis is a painless form of sub-acute thyroiditis.This is similar to post partum thyroiditis but occurs in men and the non-pregnant female. Its cause is unclear but many factors have been cited. Two outbreaks of silent thyroiditis in the USA are now known to be due to contamination of minced beef with thyroid tissue. This entity is now known as "hamburger thyrotoxicosis".
The thyroid gland is small, the thyroid overactivity is usuallymild and transient and there is little uptake on the thyroid scan. Patients with silent thyroiditis are often treated incorrectly with antithyroid durugs because the condition is mistaken for Graves disease. The use of anti-thyroid drugs is inappropriate becauseincreased hormone production is not the cause of thyrotoxicosis in painless thyroiditis. Treatment at most is a short course of beta-blockers to control the symptoms of transient overactivity. Very rarely the symptoms are so severe that a short course of steroids is indicated.
One very interesting form of silent thyroiditis is "palpation thyroiditis". Rough handling of the thyroid on clinical examination can cause significant structural changes with no thyroid hormone abnormalities. Often in the post-operative period following a parathyroidectomythere may be changes in the thyroid function and even frank transient thyrotoxicosis due to trauma to the thyroid.