Performance of Mini Parasep® SF stool concentrator kit, Kato-Katz, and formalin-ethyl acetate concentration methods for diagnosis of opisthorchiasis in Northeast Thailand

Abstract

Background Control and elimination of the liver fluke (Opisthorchis viverrini) is a primary preventive strategy against cholangiocarcinoma in Southeast Asia. A sensitive parasitological diagnostic method is required to facilitate a surveillance and control program. In this study, we evaluated the performance of Mini Parasep® SF stool concentrator kit (stool kit) compared with Kato-Katz (KK) and the quantitative formalin-ethyl acetate concentration technique (FECT) for detection of O. viverrini and co-endemic parasitic infections. Methods A cross-sectional survey for parasitic infection in residents aged > 15 years in a community in Kalasin province, Northeast Thailand, was conducted in 2018. Fecal samples were collected and screened by KK method, and a subset of samples was further examined by the stool kit and FECT methods. The results were analyzed for prevalence of parasitic infections in addition to the diagnostic performance of the methods for qualitative and quantitative detection of helminthiases. Results The initial survey of parasitic infection determined by the KK method (n = 567) showed the prevalence of O. viverrini was 32.63%, followed by Taenia 2.65%, echinostomes 1.76%, hookworms 1.41%, Trichuris trichiura 0.53% and Strongyloides stercoralis 0.53%. Within a subset of samples tested with multiple diagnostics (n = 150), the detection rates of O. viverrini by the stool kit, FECT and KK methods were 27.3%, 30.7% and 28.7%, respectively. The diagnostic sensitivity for opisthorchiasis was similar for FECT (75.5%), KK(66.0%) and the stool kit (67.3%). For other parasitic infections, FECT and stool kit methods performed better than KK, particularly in detecting minute intestinal flukes (MIF), S. stercoralis and coinfections. When measuring the intensity of O. viverrini infection (fecal egg counts), the stool kit results showed a significant positive correlation with KK and FECT (P < 0.05). Conclusions As the stool kit is simple to use and shows a comparable performance to FECT, it may serve as an alternative method of fecal examination for screening of helminthiasis including opisthorchiasis. Graphical abstract

Prevalence estimates of Opisthorchis viverrini and Clonorchis sinensis infection in the Greater Mekong subregion: a systematic review and meta-analysis

“…The diagnostic sensitivity of Kato-Katz is generally lower than that of FECT, particularly in cases of light infections [ 25 – 27 ]. However, comparable or even higher sensitivity has been reported [ 28 – 30 ]. The higher prevalence of opisthorchiasis with Kato-Katz over other methods (FECT and others) in this review during the years 2010 to 2019 is likely attributed to the datasets recruited from different geographical locations rather than the diagnostic methods.…”

Multi-epitope protein production and its application in the diagnosis of opisthorchiasis

“…The highly conserved OvCB, OvAEP, and OvCF across parasitic helminths and protozoa allow for cross-reactivity with sera from patients with other parasite-infected [ 14 , 16 , 22 ]. Furthermore, IgG antibodies persisted in O. viverrini -infected hosts after antihelmintic treatment [ 23 ], and patients with a light infection excreting fewer than 50 eggs/g feces, which were undetectable by FECT, showed positive reactivity with the recombinant protein [ 24 ]. The detection of IgG4 antibodies [ 25 ] or the engineering of recombinant protein targets using rational design and directed evolution can improve the affinity and specificity of protein target binding to specific antibodies, thereby increasing the sensitivity and specificity of diagnosis [ 26 , 27 ].…”

Application of the Midi Parasep® SF technique for the detection of L1 larvae of Angiostrongylus cantonensis in faeces of infected rats

“…The Midi Parasep® SF technique has proved to be a simpler, less toxic, rapid, and sensitive concentration technique for parasites in faeces (Adugna et al 2017;Tenorio-Abreu et al 2013). In fact, the technique proved to be more sensitive than FECT in the detection of Strongyloides stercoralis larvae in human faeces (Kopolrat et al 2022). In addition, once properly cleaned, the device can be reused, making it even more economical.…”

“…In fact, the technique proved to be more sensitive than FECT in the detection of Strongyloides stercoralis larvae in human faeces (Kopolrat et al . 2022). In addition, once properly cleaned, the device can be reused, making it even more economical.…”