Comparison of three rapid diagnostic tests for Plasmodium falciparum diagnosis in Ghana

• Published in: Malaria Journal
• Main Authors: Tolulope Adeyemi Kayode, Agyapong Kofi Addo, Thomas Kwame Addison, Austine Tweneboah, Stephen Opoku Afriyie, Dawood Ackom Abbas, Ayesha Seth, Abraham K. Badu-Tawiah, Kingsley Badu, Cristian Koepfli
• Format: Article in Journal/Newspaper
• Language: English
• Published: BMC 2024
• Subjects: Malaria diagnosis; Rapid diagnostic test; Ultrasensitive RDT; HRP2; PLDH; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Abbott; Arctic
• Online Access: https://doi.org/10.1186/s12936-024-05073-z; https://doaj.org/article/c3cb2e9340eb4b319cc34ff0c1f4ab1e

Abstract Background Accurate diagnosis and timely treatment are crucial in combating malaria. Methods A total of 449 samples were screened for Plasmodium falciparum infection by expert microscopy, qPCR, and three RDTs, namely Rapigen Biocredit Malaria Ag Pf (detecting HRP2 and pLDH on separate bands), Abbott NxTek Eliminate Malaria Ag Pf (detecting HRP2), and SD Bioline Malaria Ag Pf (detecting HRP2). hrp2/3 deletion typing was done by digital PCR. Results 45.7% (205/449) individuals tested positive by qPCR for P. falciparum with a mean parasite density of 12.5 parasites/μL. Using qPCR as reference, the sensitivity of microscopy was 28.3% (58/205), the Biocredit RDT was 52.2% (107/205), the NxTek RDT was 49.3% (101/205), and the Bioline RDT was 39.5% (81/205). When only samples with densities > 20 parasites/μL were included (n = 89), sensitivity of 62.9% (56/89) by microscopy, 88.8% (79/89) by Biocredit, 88.8% (79/89) by NxTek, and 78.7% (70/89) by Bioline were obtained. All three RDTs demonstrated specificities > 95%. The limits of detection (95% probability that a sample tested positive) was 4393 parasites/μL (microscopy), 56 parasites/μL (Biocredit, considering either HRP2 or pLDH), 84 parasites/μL (NxTek), and 331 parasites/μL (Bioline). None of the three qPCR-confirmed P. falciparum positive samples, identified solely through the pLDH target, or eight samples negative for all RDTs but qPCR-positive at densities > 20 parasites/µL carried hrp2/3 deletions. Conclusion The Biocredit and NxTek RDTs demonstrated comparable diagnostic efficacies. All three RDTs performed better than microscopy.