Decompensated Hypothyroidism in a Patient With Cirrhosis: A Rare Presentation of Severe Hypothyroidism With Hypertension.

Background/Objective: Decompensated hypothyroidism (DH) is a rare endocrine emergency with a high mortality rate, particularly challenging to distinguish from hepatic encephalopathy (HE) in patients with cirrhosis due to overlapping symptoms. Case Report: We present a case of a 79-year-old woman with advanced cirrhosis and a history of multiple HE-related admissions, who exhibited altered mental status, hypothermia, bradycardia, and unusually high blood pressure. Laboratory findings revealed a severely elevated thyroid-stimulating hormone level (335.10 µUI/mL; reference range, 0.40-4.50 µUI/mL) and low free thyroxine level (0.2 ng/dL; reference range, 0.8-1.8 ng/dL), confirming DH. Adrenal insufficiency was ruled out. Intravenous levothyroxine was administered with a dose adjustment over 4 days, leading to significant clinical improvement by hospital day 1 and recovery to baseline by day 4. Discussion: This case highlights the complexity of diagnosing and managing DH in the context of cirrhosis. Notably, the pronounced hypertension observed may reflect compensatory systemic vasoconstriction in response to a low cardiac output state. Conclusion: The complexity and severity of concomitant DH and HE underscore the necessity of prompt recognition and tailored treatment to prevent further complications.