Immunochromatographic test for rapid serological diagnosis of human angiostrongyliasis

Praphathip Eamsobhana; Anchalee Tungtrongchitr; Darawan Wanachiwanawin; Hoi-Sen Yong

doi:10.1016/j.ijid.2018.06.005

Immunochromatographic test for rapid serological diagnosis of human angiostrongyliasis

Int J Infect Dis. 2018 Aug:73:69-71. doi: 10.1016/j.ijid.2018.06.005. Epub 2018 Jun 13.

Authors

Praphathip Eamsobhana¹, Anchalee Tungtrongchitr², Darawan Wanachiwanawin³, Hoi-Sen Yong⁴

Affiliations

¹ Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand. Electronic address: praphathip.eam@mahidol.ac.th.
² Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
³ Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand. Electronic address: darawan.wan@mahidol.ac.th.
⁴ Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.

PMID: 29908250
DOI: 10.1016/j.ijid.2018.06.005

Abstract

Objectives: The serological diagnosis of human infection with Angiostrongylus cantonensis remains problematic because there are no commercially available validated tests. Most laboratories use domestically prepared tests such as the enzyme-linked immunosorbent assay (ELISA) or immunoblotting. Since laboratory facilities are not always available in endemic areas, we developed and assessed a rapid lateral flow immunochromatographic assay (AcQuick^Dx Test) to detect anti-A. cantonensis antibodies in human serum.

Methods: The test device was assembled with purified 31-kDa glycoprotein as diagnostic antigen and with gold-labelled anti-human immunoglublin-G as the detector reagent. A total of 97 serum samples were tested - 19 samples from clinically diagnosed patients with detectable A. cantonensis-specific antibody in immunoblotting; 43 samples from patients with other parasitic diseases, i.e. gnathostomiasis (n=13), toxocariasis (n=2), trichinellosis (n=2), hookworm infection (n=4), filariasis (n=5), cysticercosis (n=9), paragonimiasis (n=2), opisthorchiasis (n=3), and malaria (n=3); and 35 samples from normal healthy subjects.

Results: The sensitivity, specificity, positive predictive value and negative predictive value of AcQuick^Dx Test to detect anti-A. cantonensis specific antibodies in serologically confirmed angiostrongyliasis cases, were 100%, 98.72%, 95% and 100%, respectively. Positive AcQuick^Dx was observed in 1 of 4 cases with hookworm infections. No positive AcQuick^Dx was observed in cases with other parasitic diseases, and the individual healthy subjects.

Conclusions: AcQuick^Dx Test is rapid, highly sensitive and specific, and easy to perform without additional equipment or ancillary supplies. It yields results that are interpreted visually, and possesses a long shelf-life at room temperature. Thus, it can be applied as an additional test for clinical diagnostic support of angiostrongyliasis either in conventional laboratories or for remote areas where laboratory infrastructure is not available.

Keywords: 31-kDa antigen; Angiostrongylus cantonensis; Immunodiagnosis; Lateral flow immunochromatographic assay; Rapid test.

MeSH terms

Angiostrongylus cantonensis / immunology
Animals
Antibodies, Helminth / blood
Chromatography, Affinity / methods*
Humans
Serologic Tests
Strongylida Infections / diagnosis*

Substances

Antibodies, Helminth

Supplementary concepts

Angiostrongyliasis