Hepatotoxicity and Anti-Nuclear Antibody Positivity During Methimazole Therapy for Thyrotoxicosis: A Case Report

Abstract

Thyrotoxicosis is one of the most frequent endocrine disorders. Methimazole is the anti-thyroid drug for the treatment of hyperthyrodism. Methimazole is rarely associated with hepatic toxicity. We reported a case of 56-year-old woman who developed hepatotoxicity and anti-nuclear antibody positivity during methimazole treatment. Increased liver enzyme levels appeared after 1 month of the methimazole treatment. Viral hepatitis markers were negative. The radiological examinations were normal. According to the CIOMS/RUCAM scale, the score was 11 and the causal relationship of the hepatic adverse reaction by methimazole was highly probable. Methimazole-induced hepatotoxicity was considered and methimazole treatment was cancelled. The laboratory parameters returned to normal after 15 days. The mechanism of hepatotoxicity due to methimazole treatment was not fully understood. It has been hypothesized that there is a genetic predisposition, associated with a dose-dependent immune reaction. In conclusion, physicians should be aware the risk of hepatotoxicity related with methimazole treatment.




J Med Cases. 2015;6(1):30-32
doi: http://dx.doi.org/10.14740/jmc2009w