|Heart Sounds & Murmurs|||||Liver & Ascites|||||Neck Veins|||||Pulmonary|||||[Thyroid]|
Differential Diagnosis: Thyroid
Goiter: false positive
Not all patients you think have a large thyroid actually do.
Overestimation of the size of the thyroid can result from:
Goiter: false negative
On some patients, you may miss detecting an enlarged thyroid.
Underestimation of the size of the thyroid can result from:
Primary thyroid gland failure due to chronic autoimmune thyroiditis (Hashimoto's thyroiditis) is the most common cause of hypothyroidism. Other frequent causes are previous radioactive idine therapy for hyperthyroidism and thyroid surgery. Subclinical hypothyroidism is most commonly due to autoimmune thyroiditis, or to inadequate replacement of hypothyroidism.
The most common eitology of hyperthyroidism overall is Graves" Diseases, an immunologically mediated toxic goiter. The peak incidence is in patients in their 20's or 30's and is 5 times more likely in women than men. In the elderly, toxic nodular goiter (TNG) is more common than Graves' Disease. Other cuases of hyperthyroidisim include toxic adenoma, postpartum thyroiditis, subacute thyroiditis, and exogenous thyroid hormone ingestion.
Subacute thyroiditis is self-limited disease of viral origin that often follows an URI. Transient postpartum thyroiditis, also a self-limited disease, occurs in approximately 5% of women in the frst 3 to 6 months postpartum and increases the subsequent risk of developing primary thypothyroidism.
Thyroid cancer is rare (annual incidence of 0.004%) with low assoicated morbidity and mortality. In the US, there are 12,000 new cases of thyroid cancer and 1000 thyroid cancer related deaths annually. Almost all thyroid cancer (95%) presents as a thyroid nodule or neck mass.
Type of Thyroid Cancers (in order of decreasing frequency and increasing invasiveness)