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1、This lecture was conducted during the Nephrology Unit Grand Ground by Medical Student rotated under Nephrology Division under the supervision and administration of Prof. Jamal Al Wakeel, Head of Nephrology Unit, Department of Medicine and Dr. Abdulkareem Al Suwaida. Nephrology Division is not respon
2、sible for the content of the presentation for it is intended for learning and /or education purpose only.,Outlines:,Thyroid gland & mechanism Goiter: Definition Classification Causes Symptoms Risk factor Tests and diagnosis Treatments Lifestyle,The thyroid is a small, butterfly- shaped gland inside
3、the neck, just below the Adams apple. The thyroid gland produces hormones which control the bodys metabolism and regulate the rate at which the body carries out its functions,Definition:,A goiter is an abnormal enlargement of the thyroid gland and can occur for a number of different reasons.,Mortali
4、ty/Morbidity:,Most goiters are benign, causing only cosmetic disfigurement. Morbidity or mortality may result from compression of surrounding structures, thyroid cancer, hyperthyroidism, or hypothyroidism.,Sex and age:,The female-to-male ratio is 4:1 In the Wickham study, 26% of women had a goiter,
5、compared to 7% of men. Thyroid nodules are less frequent in men than in women, but when found, they are more likely to be malignant.,Classification:,Toxic goiter: A goiter that is associated with hyperthyroidism is described as a toxic goiter. Examples of toxic goiters include diffuse toxic goiter (
6、Graves disease), toxic multinodular goiter, and toxic adenoma,Nontoxic goiter: A goiter without hyperthyroidism orhypothyroidism is described as a nontoxic goiter. It may be diffuse or multinodular Examples of nontoxic goiters including goiter identified in early Graves disease, congenital goiter, a
7、nd physiologic goiter that occurs during puberty,Other type of classification: I - palpation struma - in normal posture of head it cannot be seen. Only found when palpating. II - struma is palpative and can be easily seen. III - struma is very big and is retrosternal. Pressure and compression marks.
8、,Causes:,Worldwide, the most common cause for goiter is iodine deficiency. In countries that use iodized salt, Hashimotos thyroiditis becomes the most common cause.,- Excess iodine or lithium ingestion, which decrease release of thyroid hormone -Goitrogens(cassava, lima beans, maize, bamboo shoots,
9、and sweet potatoes),-Inborn errors of metabolism causing defects in biosynthesis of thyroid hormones- Exposure to radiation-Thyroid hormone resistance,Side-effects of pharmacological therapy such as:Amiodarone :inhibits peripheral conversion of thyroxine to triiodothyronine; also interferes with thy
10、roid hormone action.Phenobarbitone, phenytoin, carbamazepine, Rifampcin:induce metabolic degradation of T3 and T4.,Graves disease Thyroiditis Thyroid cancer,Graves disease,ones immune system produces a protein, called thyroid stimulating immunoglobulin (TSI). As with TSH, TSI stimulates the thyroid
11、gland to enlarge producing a goiter. However, TSI also stimulates the thyroid to make too much thyroid hormone (causes hyperthyroidism).,It can also affect the eyes, causing bulging eyes (exophthalmos). It affects other systems of the body, including the skin, heart, circulation and nervous system.,
12、Thyroiditis:,it is the inflammation of the thyroidgland.This disease is often considered a malfunction of the immune system. Antibodies that attack the thyroid are what causes most types of thyroiditis. It can also be caused by an infection, like a virus or bacteria.,Hashimotos thyroiditis:,This is
13、a autoimmune condition in which there is destruction of the thyroid gland by ones own immune system.As the gland becomes more damaged, it is less able to make adequate supplies of thyroid hormone.,The pituitary gland senses a low thyroid hormone level and secretes more TSH to stimulate the thyroid.
14、This stimulation causes the thyroid to grow, which may produce a goiter.,Thyroid neoplasm or thyroid cancer,usually 4 kinds of malignant tumors of the thyroid gland:papillary, follicular, medullary or anaplastic,Symptoms:,In general: -Swelling or disfigurement of the neck -Afeeling of tightness in t
15、he throat -Coughing -Difficulty breathing -Difficulty swallowing,Hyperthyroidism:,Weight loss, heat intolerance, trembling hands, palpitations, insomnia, anxiety, increased bowel movement frequency.,Hypothyroidism:,Weight gain, cold intolerance, constipation, very dry skin, depressed mood, muscle cr
16、amping .,Symptoms of Possible Cancer Spread:,Bone pain in one spot without relief Weakness or numbness of an arm or leg that persists .,Examination of the goiter is best performed with the patient upright, sitting or standing. Inspection from the side may better outline the thyroid profile, as shown
17、 below. Asking the patient to take a sip of water facilitates inspection. The thyroid should move upon swallowing.,Palpation of the goiter is performed either facing the patient or from behind the patient, with the neck relaxed and not hyperextended. Each lobe is palpated for size, consistency, nodules, and tenderness. Cervical lymph nodes should be palpated.,
