片形吸虫病是一种人畜共患的蠕虫病，在日本零星发生。在本报告中，我们描述了一例片形吸虫病病例，该病例最初难以诊断，因为粪便检查方法对片形吸虫呈阴性。蛋。居住在日本下关市的 64 岁男性，出现疲劳和厌食症状。实验室检查显示肝功能障碍和嗜酸性粒细胞增多。腹部动态增强计算机断层扫描和磁共振胰胆管造影提示肝内胆管囊肿。此后持续发热、盗汗，怀疑恶性肿瘤，进行正电子发射断层扫描和肝门淋巴结活检。然而，组织病理学诊断发现非特异性炎症。由于嗜酸性粒细胞增多和多发性肝脏肿块，怀疑片形吸虫病，因此由外部私人实验室进行粪便虫卵检查，采用浮选法，报告没有发现寄生虫卵。然而，我们实验室使用福尔马林-乙醚浓缩法重试粪便检查，结果检测到片形吸虫。蛋。本病例提示，根据粪便检查方法的不同，可能会出现误诊；因此，有必要针对某些寄生虫种类选择合适的方法。版权所有 © 2023 日本化疗学会、日本传染病协会和日本感染预防控制学会。由爱思唯尔有限公司出版。保留所有权利。

Fascioliasis, a zoonotic helminthiasis, occurs sporadically in Japan. In this report, we describe a case of fascioliasis that was initially difficult to diagnose because the fecal examination method was negative for the Fasciola sp. eggs. A 64-year-old man living in Shimonoseki City, Japan, presented with fatigue and anorexia. Laboratory tests showed hepatic dysfunction and eosinophilia. Abdominal dynamic contrast-enhanced computed tomography and magnetic resonance cholangiopancreatography suggested intrahepatic biliary cysts. Thereafter, fever and night sweats persisted, and positron emission tomography and biopsy of the porta hepatis lymph node were performed on suspicion of malignancy. However, histopathological diagnosis found non-specific inflammation. As fascioliasis was suspected due to eosinophilia and the multiple hepatic masses, fecal egg examination was performed by an external private laboratory, which adopted the flotation method and reported the absence of parasite eggs. However, fecal examination was retried in our laboratory using the formalin-ether concentration method, and we detected Fasciola sp. eggs. This case suggests that misdiagnosis may occur depending on the fecal examination method; thus, it is necessary to choose a suitable method for certain parasite species.Copyright © 2023 Japanese Society of Chemotherapy, Japanese Association for Infectious Diseases, and Japanese Society for Infection Prevention and Control. Published by Elsevier Ltd. All rights reserved.