Case 3. Hashimoto’s thyroiditis :
Type IV Autoimmune disease
There may be overlap with Grave’s disease, which is manifested by agonistic (activating) antibodies reactive with the TSHR. Initially, this antibody may activate the thyroid into oversecretion of thyroid hormone (seen as increased levels of T4), leading to hyperthyroidism. Eventually, this too may cause destruction of the thyroid gland, resulting in an hypothyroid state.