Accuracy of the Kato-Katz method and formalin-ether concentration technique for the diagnosis of Clonorchis sinensis, and implication for assessing drug efficacy

作者：Qian, Men Bao; Yap, Peiling; Yang, Yi Chao; Liang, Hai; Jiang, Zhi Hua; Li, Wei; Utzinger, Juerg; Zhou, Xiao Nong; Keiser, Jennifer^*

来源：Parasites & Vectors, 2013, 6(1): 314.

DOI：10.1186/1756-3305-6-314

• Clonorchis sinensis
• Kato Katz method
• Formalin ether concentration technique
• Diagnosis
• Efficacy

Background: Clonorchiasis is a chronic neglected disease caused by a liver fluke, Clonorchis sinensis. Chemotherapy is the mainstay of control and treatment efficacy is usually determined by microscopic examination of fecal samples. We assessed the diagnostic accuracy of the Kato-Katz method and the formalin-ether concentration technique (FECT) for C. sinensis diagnosis, and studied the effect of diagnostic approach on drug efficacy evaluation.
Methods: Overall, 74 individuals aged >= 18 years with a parasitological confirmed C. sinensis infection at baseline were re-examined 3 weeks after treatment. Before and after treatment, two stool samples were obtained from each participant and each sample was subjected to triplicate Kato-Katz thick smears and a single FECT examination.
Results: Thirty-eight individuals were still positive for C. sinensis according to our diagnostic 'gold' standard (six Kato-Katz thick smears plus two FECT). Two FECT had a significantly lower sensitivity than six Kato-Katz thick smears (44.7% versus 92.1%; p <0.001). Examination of single Kato-Katz and single FECT considerably overestimated cure rates.
Conclusions: In settings where molecular diagnostic assays are absent, multiple Kato-Katz thick smears should be examined for an accurate diagnosis of C. sinensis infection and for assessing drug efficacy against this liver fluke infection.

• 出版日期2013-10-29
• 单位中国疾病预防控制中心; 广西壮族自治区疾病预防控制中心; 中国疾病预防控制中心寄生虫病预防控制所