Comparison of three antigen detection tests for diagnosis and follow-up of falciparum malaria in travellers returning to Berlin, Germany

We determined the sensitivity and specificity of three rapid immunochromatographic malarial antigen detection test systems (RDTs) for the detection of Plasmodium falciparum and assessed the quality of follow-up results. ParaSight-F and ICT Malaria detect histidine-rich protein-2 (HRP-2), whereas OptiMal detects plasmodial lactate dehydrogenase (pLDH). ParaSight-F performed with 95.1% sensitivity and 97.1% specificity (554 patients tested of whom 144 had falciparum malaria). ICT Malaria performed with 95.7% sensitivity and 99.2% specificity (718 patients tested of whom 184 had falciparum malaria). OptiMal performed with 76.2% sensitivity and 99.7% specificity (539 patients tested of whom 130 had falciparum malaria). In follow-up investigations, HRP-2 did not appear to be a useful antigen due to its long half-life, whereas pLDH offers a reasonable correlation with the presence of viable parasites in those cases initially detected. We therefore conclude that a combination of both antigens might be the best option for creating a reliable RDT for the diagnosis of falciparum malaria.