Severe Myxedema Coma With Neurological, Cardiac, and Renal Involvement: A Case Report.

Myxedema coma is the most severe manifestation of hypothyroidism, with high mortality despite treatment. It typically affects elderly women and is often triggered by infection, drug exposure, or environmental stressors. We report the case of a 66-year-old woman with no prior history of thyroid disease who presented with progressive neurological deterioration, hypothermia, bradycardia, hypotension, and multiorgan dysfunction. Laboratory evaluation confirmed severe hypothyroidism with elevated thyroid-stimulating hormone and undetectable free T4, alongside markedly elevated cardiac enzymes, global cardiomyopathy with pericardial effusion, and acute kidney injury. Management with high-dose enteral levothyroxine and intravenous hydrocortisone, in combination with supportive care, led to rapid improvement, extubation by day three, and full recovery of thyroid, cardiac, renal, and neurological function. This case underscores the importance of early recognition and timely intervention in patients with unexplained encephalopathy and systemic compromise, as prompt treatment can reverse even severe presentations of myxedema coma.