COLD CASE: MYXEDEMA COMA TRIGGERED BY PNEUMONIA

Abstract

TOPIC: Critical Care TYPE: Fellow Case Reports INTRODUCTION: Myxedema coma is severe hypothyroidism with associated hypothermia, altered mental status and multi-organ dysfunction. Mortality is over 60% and cases usually occur after a precipitating incident in patients with untreated hypothyroidism. CASE PRESENTATION: The patient is a 78 year old male with a history of congestive heart failure, diabetes, CKD, bronchiectasis, prior adenocarcinoma s/p right middle lobectomy, and untreated hypothyroidism who presented to the hospital with altered mental status. Six months prior, the patient was admitted to the hospital for pseudomonas pneumonia and had an elevated TSH at that time. On presentation, the patient was reported to have had upper respiratory symptoms for three days with generalized weakness. When he arrived to the hospital, he was found to be lethargic (GCS 6), bradycardic (35-55 bpm), hypotensive (82/36), hypoxic (50% on 2L home nasal cannula), and hypothermic (33.5C). He was given multiple doses of atropine with slight improvement in his heart rate and was started on norepinephrine and epinephrine. The patient was started on cefepime and vancomycin for antibiotic coverage after a chest x-ray was concerning for bilateral pneumonia. He was subsequently intubated for respiratory failure and altered mental status. Upon admission to the intensive care unit, the patient's condition remained unchanged despite appropriate interventions. A TSH was ordered and returned at 94.6 mU/L with a T4 of 0.04 ng/dl. He was given 300mcg of levothyroxine and 100mg of hydrocortisone IV. The patient was weaned off of pressors that day and transferred to the floor two days later. Both medications were continued during his hospital stay. Unfortunately, the patient ended up developing end stage renal disease that hospitalization and subsequently passed away while on hospice. DISCUSSION: This case offers a classic presentation of myxedema coma. In this case, the patient had known hypothyroidism but had gone untreated for months. He presented lethargic, hypotensive, hypoxic, bradycardic, and edematous. He was refractory to treatment and rapidly improved once levothyroxine was administered. The mortality for myxedema though is quite high and this patient unfortunately did not survive long term. Typical dosing of T4 should be 4mcg/kg IV (100-400mcg) and continued at 100mcg daily, which was done in this case. T3 can also be administered at 5-20mcg IV followed by 2.5-10mcg q8h, but was not done in this case. Steroids were given for this patient and are used for associated adrenal insufficiency. Typical dosing of hydrocortisone is 100mg q8h IV, but dexamethasone can be given as well. CONCLUSIONS: Myxedema coma is a rare but severe complication from hypothyroidism. An intensivist should remain vigilant about patients with hypothyroidism that present critically ill with symptoms described in this case. Early recognition and treatment is key to saving these patient's lives. REFERENCE #1: Jonklaas J, Bianco AC, Bauer AJ, et al. Guidelines for the treatment of hypothyroidism: prepared by the american thyroid association task force on thyroid hormone replacement. Thyroid. 2014;24(12):1670-1751. doi:10.1089/thy.2014.0028 REFERENCE #2: Ono Y, Ono S, Yasunaga H, Matsui H, Fushimi K, Tanaka Y. Clinical characteristics and outcomes of myxedema coma: Analysis of a national inpatient database in Japan. J Epidemiol. 2017;27(3):117-122. doi:10.1016/j.je.2016.04.002 REFERENCE #3: Kim JJ, Kim EY. Myxedema coma precipitated by diabetic ketoacidosis after total thyroidectomy: a case report. J Med Case Rep. 2019;13(1):50. Published 2019 Mar 4. doi:10.1186/s13256-019-1992-0 DISCLOSURES: No relevant relationships by Kyle Gronbeck, source=Web Response