Case Summary:

A 46-year-old female presents with unexplained weight loss (10 kg over 2 months), palpitations, heat intolerance, and tremors. She reports having a 3-month history of increased anxiety, irregular menstruation, and bulging eyes. Her thyroid gland is diffusely enlarged on examination, and she has a resting tremor.

Key Investigations:

·         Thyroid function tests: TSH < 0.01 µU/mL, Free T4 3.2 ng/dL (normal range 0.9-2.3 ng/dL), Free T3 7.8 ng/dL (normal range 2.3-4.2 ng/dL)

·         Thyroid Ultrasound: Diffuse enlargement, no nodules

·         Radioactive Iodine Uptake Scan: Increased uptake diffusely

Questions:

1.      What is the most likely diagnosis based on the patient's clinical presentation and lab results?

2.      Discuss the pathophysiology of hyperthyroidism in this patient, and how it leads to her clinical symptoms.

3.      What are the treatment options for this patient, and how would you manage her thyroid hormone levels?

4.      What are the potential complications of untreated hyperthyroidism, especially in relation to her cardiovascular system?

5.      Explain the role of radioactive iodine therapy and antithyroid medications in the management of hyperthyroidism.

References:

·         American Thyroid Association (ATA) Guidelines, 2023.

·         Ross, D.S., et al. (2021). "Thyroid Disease: Diagnosis and Management." New England Journal of Medicine.