However, if the sTSH is abnormal, further testing is required to determine the cause of the alteration in the TSH and to characterize the thyroid status of the patient. I. Hyperthyroidism Hyperthyroidism can be defined as a condition of excessive functional activity of the thyroid gland and excess secretion of thyroid hormones marked by tachycardia or atrial fibrillation, widened pulse pressure, palpitations, fatiguability, nervousness and tremor, heat intolerance and excessive sweating, warm, smooth moist skin, weight loss, muscular weakness, hyperdefacation, emotional liability and ocular signs. Sometimes, goiter may be present. Hypothyroidism Hypothyroidism can be defined as a deficiency of the thyroid activity. It is characterized by decrease in basal metabolic rate, tiredness and lethargy, sensitivity to cold and menstrual disturbances.
Secondary hypothyroidism is due to pituitary deficiency of thyrotropin secretion.
Compensated hypothyroidism is considered a common entity. However, treatment is controversial. Many patients over 70 years have this finding, but do not become hypothyroid. Compensated hypothyroidism may or may not ever progress to the point where thyroxine replacement therapy is justified. A normal or low level of sTSH may confirm euthyroidism.