The wide range and vague nature of clinical presentations of thyroid emergencies make accurate and timely diagnosis challenging. Patients with a variety of thyroid conditions present to the emergency department, and appropriate suspicion can reduce unnecessary delay and expense in determining the correct diagnosis. This issue reviews the current evidence for presentation, evaluation, and treatment for emergencies of thyroid function and anatomy including hypothyroidism, hyperthyroidism, thyroid nodules, and thyroid trauma. Complications of thyroid dysfunction are also considered, as well as recommendations for disposition and follow-up.

A 4-year-old boy presents to your ED, asymptomatic after suspected ingestion of 25 tablets of his grandmother’s 300-mcg levothyroxine. The ingestion occurred 90 minutes ago. You wonder: Is this amount toxic? Would serum hormone levels be helpful? What symptoms would be concerning? How should this patient be managed?

An 8-year-old boy with a history of Down syndrome is brought in by his parents because he is lethargic. He is difficult to rouse and has a history of vomiting and diarrhea for the last 4 days. His parents say this is very unusual for him, as he is usually constipated. The boy responds slowly to voice and shows signs of dehydration on examination. His mucous membranes are tacky, his capillary refill is 4 seconds, and he has cool extremities. The patient’s heart rate is 135 beats/min and his blood pressure is 100/60 mm Hg. A review of systems reveals no recent weight change, no unusual hair growth, and no temperature intolerance. In the waiting room, oral rehydration by syringe has been unsuccessful. While you suspect that dehydration is the cause of this patient's condition and begin to calculate fluid replacement, you recall that constipation can be a symptom of thyroid disease. Should you check the patient's thyroid stimulating hormone level while you start intravenous rehydration?