Hyperthyroidism and Graves disease — formative SAQs

SAQ 1 (10 marks)

A thirteen-year-old girl presents over four months with palpitations, a tremor, a five-kilogram weight loss despite an increased appetite, heat intolerance, anxiety and declining school performance. Her mother has noticed that her eyes look prominent. Examination reveals a heart rate of 110 beats per minute, a bounding pulse with a blood pressure of 130/60 mmHg, a fine tremor, lid retraction and mild proptosis, and a diffuse, smooth goitre with an audible bruit. Her thyroid function shows a TSH of less than 0.05 mU/L, a free T4 of 38 pmol/L and a positive TSH-receptor antibody. ^{[1] [3]}

a) Give the diagnosis and explain how the clinical and biochemical picture arises from the underlying autoimmune mechanism. (3 marks) ^[1]

b) Outline the immediate and long-term pharmacological management, naming the first-line antithyroid drug, the role of the beta-blocker, the two dosing regimens, and the reason propylthiouracil is avoided. (3 marks) ^{[1] [6] [9]}

c) Describe the two drug dangers that must be explained to the family at every prescription, their presenting features, and the immediate response. (2 marks) ^[9]

d) Discuss the prognosis after a two-to-three-year course of antithyroid drugs, the relapse rate, and the factors that predict relapse. (2 marks) ^{[5] [6]}