Myxedema coma in a patient with Down's syndrome.

INTRODUCTION: hyroid dysfunction is common in Down's syndrome, most common being hypothyroidism. Longstanding, untreated hypothyroidism can lead to myxedema coma. METHODS: Here we report a patient with Down's syndrome who presented with myxedema coma. DISCUSSION: The three essential elements for the diagnosis of myxedema coma include altered mental status, defective thermoregulation and a precipitating event or illness; all of these were present in our patient. Also, very high TSH, low T3 and T4, and the rapid response to the treatment with levothyroxine confirmed the diagnosis. CONCLUSION: Patients with Down's syndrome should have regular screening for thyroid dysfunction.