Evaluation of a user-friendly test device (AcQuickDx) for detection of specific antibodies to human angiostrongyliasis

Abstract

This study was conducted to evaluate the reliability of a recently developed AcQuick Test based on lateral flow immunochromatographic assay to detect the 31-kDa specific antibody against Angiostrongylus cantonensis for rapid serodiagnosis of angiostrongyliasis in patient-derived sera from the parasite endemic areas of northeast Thailand. The diagnostic performance of the assay was evaluated with a total of 184 serum samples from clinically diagnosed patients with eosinophilic meningitis due to A. cantinensis infection (n=98), and individuals at risk of infection with no evidence of eosinophilic meningitis (n=86). The serological AcQuick results were then compared with previous performance results based on dot-immunogold filtration assay (Ac-DIGFA) and dot-blot enzymelinked immunosorbent assay (dot-blot ELISA) to determine its validity. The overall positivity rate of AcQuick in 98 clinically diagnosed cases from three highly endemic districts in Khon Kaen province was 39.79%. Among the 86 sera of subjects at risk of infection with A. cantonensis, 24.41% were positive by AcQuick. The positivity rates were comparable with the results obtained previously in both groups of defined serum samples: Ac-DIFGA, 39.79% and 24.41% respectively; and dot-ELISA, 37.75% and 23.25% respectively. This study demonstrated that AcQuick is equally sensitive and specific as Ac-DIGFA and dot-blot ELISA for clinically confirmed eosinophilic meningitis caused by A. cantonensis infection. In addition to rapidity and ease of performance, the dry-format lateral flow assay in AcQuick Test allows shipment and storage without requiring a cold chain and is thus more suitable for use in remote and resource-limited settings.