Jin Yan, Shen Chenghua, Huh Sun, Sohn Woon-Mok, Choi Min-Ho, Hong Sung-Tae
Department of Parasitology and Tropical Medicine, Institute of Endemic Diseases, Seoul National University College of Medicine, Seoul 110-799, Korea.
Korean J Parasitol. 2013 Aug;51(4):433-9. doi: 10.3347/kjp.2013.51.4.433. Epub 2013 Aug 30.
Toxocariasis is a worldwide zoonosis caused by larvae of ascarid nematodes of dogs or cats, Toxocara canis or T. cati. Diagnosis of human toxocariasis currently relies on serology that uses T. canis excretory-secretory antigen to detect specific IgG antibodies by ELISA. We investigated the serodiagnostic efficacy of ELISA using crude antigen of T. canis larvae (TCLA). Serum specimens of 64 clinically confirmed toxocariasis, 115 healthy controls, and 119 other tissue-invading helminthiases were screened by ELISA using TCLA. The ELISA using TCLA showed 92.2% (59/64 patient samples) sensitivity and 86.6% (103/119) specificity. Its positive diagnostic predictivity was 78.7% and negative predictivity was 97.8%. No serum of healthy controls reacted but that of anisakiasis (45.5%), gnathostomiasis (19.2%), clonorchiasis (15.8%), sparganosis (11.1%), and cysticercosis (6.3%) cross-reacted. Immunoblot analysis on TCLA recognized antigenic proteins of 28- and 30-kDa bands in their dominant protein quantity and strong blotting reactivity. The present results indicate that the ELISA using our TCLA antigen is acceptable by the sensitivity and specificity for serodiagnosis of human toxocariasis. ELISA with TCLA is recommended to make differential diagnosis for patients with any sign of organ infiltration and eosinophilia.
弓首蛔虫病是一种由犬或猫的蛔虫线虫幼虫，即犬弓首蛔虫或猫弓首蛔虫引起的全球性人畜共患病。目前人类弓首蛔虫病的诊断依赖于血清学检测，该检测使用犬弓首蛔虫排泄分泌抗原通过酶联免疫吸附测定（ELISA）来检测特异性IgG抗体。我们研究了使用犬弓首蛔虫幼虫粗抗原（TCLA）的ELISA的血清学诊断效力。使用TCLA通过ELISA对64例临床确诊的弓首蛔虫病患者、115例健康对照者以及119例其他组织侵袭性蠕虫病患者的血清标本进行了筛查。使用TCLA的ELISA显示敏感性为92.2%（59/64例患者样本），特异性为86.6%（103/119）。其阳性诊断预测值为78.7%，阴性预测值为97.8%。健康对照者的血清无反应，但异尖线虫病（45.5%）、颚口线虫病（19.2%）、华支睾吸虫病（15.8%）、裂头蚴病（11.1%）和囊尾蚴病（6.3%）的血清出现交叉反应。对TCLA进行的免疫印迹分析识别出28 kDa和30 kDa条带的抗原蛋白，其蛋白量占主导且印迹反应强烈。目前的结果表明，使用我们的TCLA抗原的ELISA在人类弓首蛔虫病血清学诊断的敏感性和特异性方面是可接受的。建议使用TCLA的ELISA对有任何器官浸润和嗜酸性粒细胞增多迹象的患者进行鉴别诊断。
