ODP491 Levothyroxine Withdrawal Presenting as Myxedema Madness

Abstract Introduction Myxedema coma, a medical emergency, refers to severe hypothyroidism which can be precipitated by several factors including acute infection, myocardial infarction, and hypothermia. Rarely, patients may present with myxedema psychosis which manifests as suicidal ideations, hallucinations and or delusions. Case Presentation A 60-year-old woman with a history of hypertension, hypothyroidism, anxiety disorder and heroin abuse on methadone 50 mg every day presented to the hospital with acute onset of altered mental status. Per the patient, she called 911 for "cardiac arrest and talking about dead bodies". Upon presentation, the patient was hypertensive, 184/124mmHg. Physical exam was notable for active hallucinations. She was alert and oriented to person and place, with an unsteady gait. Laboratory examination was remarkable for hyponatremia 131 mmol/L (137-147 mmol/L). She received workup for acute encephalopathy and ED physicians determined that if the workup was negative, she should be evaluated by Psychiatry. Infectious processes and drug intoxication/overdose were ruled out. Psychiatry determined that the patient's psychosis was due to an organic etiology. Follow-up laboratory showed TSH 155 ulU/mL (0.350-4.80 ulU/mL), free thyroxine 4 < 0.1 ng/dL (0.90-1.8 ng/dL) and thyroid peroxidase antibody 460 IU/ml (<34.9). While in the ICU, she became bradycardic, heart rate 25 bpm, and hypoxic, O2 saturation ∼ 75%. She was placed on nasal cannula with improved oxygenation. Later she experienced two seizures lasting approximately 1 minute. The patient received stress dose steroids intravenously every 8 hours and levothyroxine intravenously. Adrenal insufficiency workup was within normal limits. On hospital day 3, her mental status improved and she was transitioned to oral levothyroxine. The patient was transferred to the medical floor for further care. Upon questioning, she reported she stopped taking her levothyroxine for approximately 6 months. Her delusions decreased and later resolved on hospital day 10. She was discharged home with 100 mcg oral levothyroxine and outpatient follow-up with Endocrinology. Conclusion Our patient presented with a rare manifestation of severe hypothyroidism, myxedema madness. The relationship between psychosis and thyroid dysfunction has long been documented. In the same period, there has only been a few reported cases of myxedema madness in literature, generally reported in Psychiatric journals. This is surprising, given that these are endocrinological emergencies. Importantly, patients with an acute presentation of psychosis, should be tested for thyroid abnormalities, as this is reversible. In our patient's case, she had no previous documented psychiatric history. It is reasonable therefore to conclude that, herlikely myxedema madness resulted from prolonged thyroid replacement non-compliance. Presentation: No date and time listed