Myxedema Coma: A Forgotten Medical Emergency With a Precipitous Onset

Abstract

Myxedema coma is a rare life-threatening disorder characterized by severe hypothyroidism leading to multiorgan failure and even death. This case also reminds clinicians that the misnomer "coma" is misleading, and the patient can present with less severe symptoms. We present a case of a 72-year-old female with a history of primary hypothyroidism who presented to the emergency department with progressively worsening confusion for three days. Laboratory results revealed thyroid-stimulating hormone (TSH) 402.0 µU/L and free thyroxine (T4) 0.22 ng/dL. The patient was compliant with the levothyroxine but she found to be malnourished on presentation. The patient was treated with intravenous levothyroxine and liothyronine. The patient's mental status improved to the baseline, and she was discharged to a skilled nursing facility. Myxedema coma is a rare but life-threatening disorder that providers should be familiar with, including management and treatment. To the best of our knowledge, this is the highest TSH level ever reported so far, and the first case of myxedema coma precipitated due to malnutrition.

Myxedema coma

“…In older adults, T4 to T3 conversion may be weakened, supporting the idea of administering T3 replacement with I.V. liothyronine 6. Additionally, intracellular T3 deficiency can lead to cardiogenic shock, hypoxia, and coma.…”

“…Additional care measures include passive rewarming for patients with hypothermia. 6 Treatment Due to the low incidence of MC and limited availability of clinical trials comparing different treatment regimens, treatment guidelines are most often based on expert opinion and provider experience. 6 One mainstay of pharmacotherapy is T4.…”

“…6 Aggressive thyroid hormone treatment carries significant risks as rapid administration may cause myocardial infarction or fatal dysrhythmias. 6,8 Electrolytes and dextrose may also be administered to correct hyponatremia and hypoglycemia. 4 Broadspectrum antibiotic coverage may be administered due to the high incidence of infections and the correlated higher mortality of undiagnosed infections.…”

“…The principal features of MC include altered mental status, decreased thermogenesis that accompanies the decrease in metabolism leading to hypothermia, and a precipitating event 7. In addition to hypothermia, signs of MC include hypotension, hyponatremia, hypoglycemia, hypoventilation, bradycardia, and soft tissue nonpitting edema of the hands and face 6. Facial and orbital edema are typically related to deposits of albumin and mucin in the skin and surrounding soft tissue 6.…”

“…TSH typically falls at a rate of 50% per week and failure to do so indicates inadequate therapy. Once a patient with MC is clinically improving, daily oral levothyroxine can be administered 6…”