A Case of Methimazole-Induced Acute Pancreatitis With an HLA Allele Causing Antithyroid Drug-Induced Agranulocytosis.

Abstract

Among the side effects of methimazole (MMI) for the treatment of Graves' disease, MMI-induced acute pancreatitis (MIP) is a rare adverse reaction, with only 7 cases being reported to date. However, 2 large-scale population-based studies recently revealed that the risk of MIP was significantly higher, ranging from 0.02% to 0.56%. Although MIP is common in middle-aged and elderly Asian women, its pathogenesis remains largely unknown. We herein present a case of a 72-year-old Japanese woman with Graves' disease who developed MIP 12 days after the initiation of MMI. The MMI was discontinued, the patient was switched to propylthiouracil (PTU) therapy, and pancreatitis gradually resolved. Serological human leukocyte antigen (HLA) typing identified HLA-DRB1*08:03:02. This HLA allele was previously detected in a patient with MIP and is one of the major risk factors for agranulocytosis induced by antithyroid drugs, including PTU as well as MMI. In cases of MIP, PTU is being considered as an alternative to MMI; however, its safety needs further investigation and patients require close monitoring after the switch to PTU. Further studies are warranted, particularly on the relationship between MIP and the presence of HLA alleles causing antithyroid drug-induced agranulocytosis.

• Authors: Yusuke Yoshimura, Keita Tatsushima, Yukiko Goshima, Yoshitomo Hoshino, Saki Nakashima, Tatsuro Inaba, Sara Ikeda, Daisuke Hattori, Rikako Koyama, Tsunao Imamura, Akira Takeshita, Yasuhiro Takeuchi
• Journal: Journal of the Endocrine Society (J Endocr Soc) Vol. 6 Issue 5 Pg. bvac038 (May 01 2022) ISSN: 2472-1972 [Electronic] United States
• PMID: 35402762 (Publication Type: Case Reports)
• Copyright: © The Author(s) 2022. Published by Oxford University Press on behalf of the Endocrine Society.