Graves disease

Autoimmune Disease

1. GRAVES DISEASE

2. Thyroid gland The thyroid gland is a butterfly-shaped endocrine gland that is normally located in the lower front of the neck. The thyroid’s job is to make thyroid hormones, which are secreted into the blood and then carried to every tissue in the body. Thyroid hormone helps the body use energy, stay warm and keep the brain, heart, muscles, and other organs working as they should.

3. GRAVES DISEASE It is an autoimmune disease in which the patient's own immune system attacks the thyroid gland, causing it to produce too much thyroxine. Thyroxine (T4) is a hormone produced by the thyroid gland that has four iodine molecules attached to its molecular structure. T4, as well as other thyroid hormones help regulate growth and control metabolism in the body. Although Graves' disease may develop at any age in both women and men, it more commonly affects women aged 20 years or more. Currently, there are no medications or treatment to stop the patient's immune system from attacking their thyroid gland. However, treatments do exist which can ease the symptoms and bring down the production of thyroxine.

4. The syndrome typically includes two major categories of phenomena:. Those specific to Graves’ disease, and caused by the autoimmunity include the exophthalmos, thyroid enlargement and thyroid stimulation, and the dermal changes. The second set of problems is caused by the excess thyroid hormone. This thyrotoxicosis, or hyperthyroidism, does not differ from that induced by any other cause of excess thyroid hormone.  It is an autoimmune condition that affects Thyroid function, causing enlargement and overactivity (hyperthyroidism) of the Thyroid.

5. Epidemiology 100-200 cases per 100,000 every year, internationally. Significantly higher incidence in women, 7:1 ratio. Most common amongst young women, but can occur at any age. Most seen between the ages of 20-40 No definitive genetic linkage.

6. Signs and Symptoms Most distinct signs, bulging eyes (Exophthalmos), pretibial myxoedema and thyroid acropachy Enlargement of the Thyroid (Goitre) Increased appetite, coupled with weight loss Heat intolerance and diaphoresis Hyperactivity and fatigability

7. Pathophysiology Autoantibodies (TSI, TBII, TGI) target and bind to TSH Receptors. Autoantibodies act like TSH (thyrotropin), causing excessive release of T3 and T4 into the blood. This spike in Thyroid hormone release, causes TSH levels to decrease (negative feedback) Pathophysiology Exophthalmos is caused by antibodies attacking the eye muscle fibroblasts, forcing a change into adipose tissue. The resulting adipose tissue builds up, exerting a pressure behind the eyes. ● Pressure build up constricts draining veins, resulting in oedema The increases in appetite and weight loss, the heat intolerance and diaphoresis, are caused by the Thyroid hormones increasing the Basal Metabolic Rate Hyperactivity and Fatigability occurs as Thyroxine overstimulates the motor end plate of the neuromuscular junction.

8. Diagnosis A blood test is carried out, checking for increased free Thyroxine and Triiodothyronine levels in the blood. Exophthalmos and non-pitting pretibial myxoedema are unique features for Grave’s Disease when coupled with hyperthyroidism. Confirmatory.

9. Prognosis With treatment the prognosis is normally very positive, without any major complications barring any that may arise from thyroidectomy. Without treatment there are long term health problems; excessively dry eyes, blindness, continued muscle degradation etc. Treatment ● Antithyroid drugs (methimazole) ● Radioiodine ● Thyroidectomy