Analysis of 90 cases of antithyroid drug-induced severe hepatotoxicity over 13 years in China.

Antithyroid drug (ATD)-induced severe hepatotoxicity is a rare but serious complication of ATD therapy. The characteristics of severe hepatotoxicity have been reported in only a small number of patients. Ninety patients with ATD-induced severe hepatotoxicity presenting during a 13 year period (2000-2013) who were about to undergo nuclear medicine therapy with (131)I from a sample of 8864 patients with hyperthyroidism were studied, and the outcomes were evaluated. The mean age of the patients with ATD-induced severe hepatotoxicity was 41.6±12.5 years (mean±standard deviation), and the female to male ratio was 2.2:1. The methimazole (MMI) dose given at the onset was 19.1±7.4 mg/day. The propylthiouracil (PTU) dose given at the onset was 212.8±105.0 mg/day. ATD-induced severe hepatotoxicity occurred in 63.3%, 75.6%, and 81.1% of patients within 4, 8, and 12 weeks of the onset of ATD therapy, respectively. The types of severe hepatotoxicity did not differ significantly between the MMI and PTU groups (p=0.188). The frequency of the cholestatic type in the MMI group (35.3%, 18/51) was higher than that in the PTU group (17.9%, 7/39), but these frequencies were not significantly different (p=0.069). The patients who were treated with (131)I received an average dose of 279.1±86.1 MBq (n=84). Therapy was successful in 60 of the 67 patients (89.6%). The success rate was equivalent (p=0.696) between the groups receiving MMI (91.7%, 33/36) and PTU (87.1%, 27/31). Severe hepatotoxicity tends to occur within the first three months after the onset of ATD therapy. The type of ATD-induced severe hepatotoxicity did not differ between the MMI and PTU groups. (131)I therapy is an effective treatment approach for patients with ATD-induced severe hepatotoxicity.