Myxedema as a Reversible Cause of Ischemic Hepatitis: Severe Hashimoto’s Hypothyroidism Presenting with Profound Bradycardia, Hypotension and Marked Hypertransaminasemia: Myxedema-Induced Ischemic Hepatitis

Abstract

Background. Ischemic (hypoxic) hepatitis, the “shock liver” of the emergency setting, follows a fall in hepatic oxygen delivery, usually from cardiac, circulatory or respiratory failure, and produces a steep but short-lived rise in liver transaminases. Severe primary hypothyroidism is a classic yet easily forgotten cause of a reversible low-output circulation, and it can present first in the liver.

Case report. A 65-year-old man with no known thyroid disease presented to the emergency department with severe hypotension (60/40 mmHg) and bradycardia (45 beats/min) and marked hepatocellular injury (aspartate aminotransferase, AST, 1643 U/L; alanine aminotransferase, ALT, 819 U/L), with a minimally raised troponin and acute kidney injury. Lactate dehydrogenase was disproportionately elevated (LDH 1279 U/L; ALT-to-LDH ratio 0.7) and creatine kinase was markedly raised (CK 2946 U/L), while synthetic function was preserved. Viral serology was negative and the liver was structurally normal. As blood pressure recovered, the transaminases fell rapidly and the AST-to-ALT ratio reversed (from 2.0 to 0.3 by day 6). A coarse voice present for several weeks prompted thyroid testing, which showed TSH 80.371 mU/L, suppressed free hormones and anti-thyroid peroxidase antibodies of 848.77 IU/mL, establishing Hashimoto’s thyroiditis. Both the circulation and the liver recovered with fluids and levothyroxine.

Conclusion. In an obtunded, bradycardic, hypotensive patient with marked transaminase elevation and no viral, autoimmune or toxic explanation, severe hypothyroidism should be considered early. The ALT-to-LDH ratio and the reversal of the AST-to-ALT ratio help identify an ischemic mechanism, a markedly raised creatine kinase signals a coexisting hypothyroid myopathy contributing to the AST, and a single thyroid-stimulating hormone can redirect the entire differential.