TSH (THYROID STIMULATING HORMONE)

• 0.35 -5.50 uI U/ml

Pediatric normal range-

• Birth to 4 days-1.0 -39 .0 uI U/ml
• 2 to 20 weeks- 1.7 to 9.1 uI U/ml

• TSH is produced by the Anterior Pituitary. It stimulates the thyroid to release the hormones Thyroxine (T4) and Triiodothyronine(T3) into the blood. TSH along with its regulatory hormone Thyrotropin releasing hormone (TRH) is part of the feedback system to maintain stable amounts of thyroid hormones in the blood
• If the Thyroid releases inappropriately large amounts of T4 and T3, there will be symptoms associated with Hyperthyroidism (Rapid heart rate, weight loss, nervousness, hand tremors, irritated eyes, difficulty sleeping). Graves disease is the most common cause of Hyperthyroidism
• If there is decreased production of Thyroid hormones, there will be symptoms associated with Hypothyroidism (weight gain, dry skin, constipation, cold intolerance, fatigue). Hashimoto Thyroiditis is the most common cause of Hypothyroidism

• When there is s/s of Hyperthyroidism (Increased heart rate, Anxiety, weight loss, difficulty sleeping, tremors in the hands, weakness, Menstrual irregularity)
• When there is s/s of Hypothyroidism (Weight gain, Dry skin, Constipation , Cold Intolerance, puffy skin , hair loss, fatigue , menstrual irregularity)

• Primary untreated hypothyroidism
• Hashimoto’s thyroiditis including those with clinical hypothyroidism
• Other conditions such as –iodine deficiency goitre, iodine induced goitre or lithium treatment

• Hyperthyroidism (due to Toxic multi nodular goitre , Autonomously functioning thyroid adenoma, Treated Grave’s disease , Thyroiditis, Extra thyroidal thyroid hormone source
• Over replacement of thyroid hormone in treatment of hypothyroidism
• Secondary pituitary or hypothalamic hypothyroidism
• Euthyroid Sick patients
• Drugs- L Dopa , Glucocorticoids, phenytoin