Accuracy of a multispecies rapid diagnostic test kit for detection of malarial parasite at the point of care in a low endemicity region

Summary 

Although highly accurate rapid diagnostic tests (RDT) for Plasmodium falciparum [based on identification of histidine-rich protein-2 (PfHRP2)] have been developed, the accuracy of non-falciparum tests is relatively poor. Recently, a Plasmodium vivax-specific RDT [based on identification of species-specific lactate dehydrogenase (PvLDH)] became available, which along with PfHRP2 may improve malaria diagnosis by identifying the species correctly. A cross-sectional hospital-based study was designed to evaluate the diagnostic accuracy of FalciVax, a commercially available PfHRP2- and PvLDH-based RDT (index test), using malaria microscopy as a reference standard. All consecutive inpatients who presented with fever underwent both the index test and the reference standard. The study sample included 657 patients and the overall sensitivity and specificity of the RDT for diagnosis of any malarial species were 92.9% and 98.4%, respectively. The diagnostic accuracy estimates for correct species identification were lower (sensitivity 91.8%, specificity 96.8%). The accuracy of the PvLDH test to detect P. vivax was low (sensitivity 76.6%, specificity 98.1%).

Keywords: Malaria, Rapid diagnostic test, Microscopy, Diagnostic accuracy, Sensitivity, Specificity