hormonal and metabolic disorders
Hypothyroidism
Causes of Hypothyroidism
Hypothyroidism may be Primary Secondary Primary hypothyroidismresults from a disorder of the thyroid gland itself. Themost commoncause in the United States is Hashimoto Thyroiditis : Hypothyroidism develops as the thyroid is gradually destroyed. Other causes of primary hypothyroidism include Thyroid inflammation (thyroiditis) Treatment of Treatment or Lack of iodine Radiation to the head and neck Inherited disorders that prevent the thyroid gland from making or secreting enough hormones can cause temporary hypothyroidism. Subacute Thyroiditis is probably caused by an infection with a virus. Autoimmune inflammation that occurs after childbirth ( Treatment with medications or in the diet is the most common cause of hypothyroidism in many developing countries. However, Iodine Deficiency is a rare cause of hypothyroidism in the United States because iodine is added to table salt and is also used to sterilize the udders of dairy cattle and thus is present in dairy products. Radiation to the head and neck,usually given as radiation therapy to treat cancer, can also cause hypothyroidism. Rarer causes of hypothyroidism include some inherited disorders in which an abnormality of the enzymes in thyroid cells prevents the gland from making or secreting enough thyroid hormones (see also Hypothyroidism in Infants and Children ). Secondary hypothyroidismoccurs when the pituitary gland fails to secrete enough thyroid-stimulating hormone (TSH), which is necessary for normal stimulation of the thyroid. Secondary hypothyroidism is much rarer than primary. 