探索肺吸虫致胸腔积液的临床诊断经验，避免误诊或延误诊断。

回顾性分析2018年5月至2022年12月十堰市太和医院呼吸与危重症医学科收治的6例肺吸虫感染所致胸腔积液患者的临床资料及诊治过程。收集患者人口学特征、临床症状、暴露史、实验室指标、胸水细胞学检查、胸膜活检组织病理学检查、肺吸虫特异性抗原皮内试验、抗寄生虫治疗后转归以及后期随访结果。

分别有3例男性、3例女性患者入组，平均年龄为（46.5 ± 5.1）岁。患者外周血嗜酸性粒细胞绝对计数和百分比均不同程度升高（12.6%~54.0%）；4例患者胸水细胞学显示存在少量或大量嗜酸性粒细胞；4例患者行内科胸腔镜胸膜活检，其中3例提示间质可见嗜酸性粒细胞广泛浸润，1例患者可见寄生虫虫卵，另1例患者显示非特异性炎症。6例患者中4例有生食淡水蟹或饮用溪水的暴露史，同时6例患者肺吸虫特异性抗原皮内试验（IDTPA）阳性和血清肺吸虫抗体酶联免疫吸附试验（ELISA）阳性，排除肺外脏器肺吸虫感染，诊断为肺吸虫所致胸腔积液。6例患者均接受口服吡喹酮治疗（25 mg/kg、3次/d，连用3 d为1个疗程，间歇7 d后行第2个疗程），胸部计算机断层扫描（CT）随访显示治疗后胸腔积液减少或消失。

在诊断不明原因胸腔积液时，对于外周血、胸水或胸膜组织嗜酸性粒细胞异常增多，且生食淡水蟹或者生溪水的患者应高度怀疑肺吸虫感染所致胸腔积液，尤其是来自肺吸虫感染流行地区的患者。

To explore the clinical diagnosis experience of pleural effusion caused by paragonimus infection, so as to avoid misdiagnosis or delayed diagnosis.

The clinical data and treatment of 6 patients with exudative pleural effusion caused by paragonimus infection in the Department of Respiratory and Critical Care Medicine of Taihe Hospital of Shiyan City from May 2018 to December 2022 were analyzed, retrospectively. Data included the demographic characteristics, clinical symptoms, exposure history, laboratory results, pleural fluid cytology, pleural biopsy histopathology, intradermal test for paragonimus-specific antigen, outcome of antiparasitic treatment and follow-up results of 6 patients were collected, respectively.

Three male and three female patients were enrolled, with a mean age of (46.5 ± 5.1) years old. The absolute count and percentage of eosinophils in peripheral blood elevated to varying degrees (12.6%-54.0%). Cytological examination of pleural fluid of four patients showed a small to large number of eosinophils. Four patients underwent thoracoscopic pleural biopsy, of which 3 patients showed extensive eosinophilic infiltration in the interstitium, 1 patient showed parasite eggs and 1 patient showed nonspecific inflammation. There were 4 cases among the 6 patients had a history of intaking fresh water crabs or stream water. Meanwhile, 6 patients were positive in intradermal test of paragonimus-specific antigen (IDTPA) and serum enzyme-linked immunosorbent assay (ELISA) for paragonimus antibody. Paragonimus infection in extrapulmonary organs was excluded and pleural effusion caused by paragonimus was confirmed. All the 6 patients received oral praziquantel treatment (25 mg/kg, 3 times a day, continuous 3 days as a course of treatment, intermittent 7 days and then the second course). Chest computed tomography (CT) showed reduced or disappeared pleural effusion after treatment.

In the diagnosis of unexplained pleural effusion, paragonimus infection should be highly suspected in patients with elevated eosinophils in peripheral blood, pleural fluid, or pleural tissue, and with a history of raw freshwater crab or stream water intaking, especially in patients from areas which paragonimus infection is endemic.