A 20-year-old woman was referred to the emergency department with rapid acceleration of complaints of palpitations, fever, diarrhea, and agitation that had been present for several weeks. During physical examination, the patient was uncomfortable and restless with a tachycardia of 170/minute, and a fever of 38.5 °C. Palpation of the neck revealed a small ventral, painless, solid elastic mass, more prominent on the right side, clinically suspicious for goiter. An electrocardiograph showed an atrial flutter of 150/min. Initial laboratory results showed an erythrocyte sedimentation rate of 35 mm/hour (0–20 mm/hour) and urine analysis tested positive for ketones.

The patient was presumed to be suffering from a thyroid storm. She was treated promptly with Propranolol 160 mg and Thiamazole 30 mg twice daily at the emergency department. She was admitted to the Cardiac Care Unit for observation of the heart rhythm, which slowed down to 110/minute the same day and her condition improved clinically. The following day her laboratory result confirmed the diagnosis with a thyroid-stimulating hormone of < 0.01 mIU/L (0.4–4.0 mIU/L) and a free thyroxine (T4) of > 75 pmol/l (10–22 pmol/l). Eventually, she was diagnosed with Graves Disease.

Thyroid storm is an acute, life-threatening, hypermetabolic state induced by excessive release of thyroid hormones. The adult mortality rate is high (90%) if early diagnosis is not made and the patient is left untreated. Therefore, in case of clinical suspicion for thyroid storm, it is critical to start prompt treatment with Beta blockade and Thiamazole before the diagnosis can be confirmed biochemically.