Evaluation of the rapid diagnostic test CareStart pLDH Malaria (Pf-pLDH/pan-pLDH) for the diagnosis of malaria in a reference setting

• Main Authors: Heutmekers Marloes, Gillet Philippe, Maltha Jessica, Scheirlinck Annelies, Cnops Lieselotte, Bottieau Emmanuel, Van Esbroeck Marjan, Jacobs Jan
• Format: Article
• Language: English
• Published: BMC 2012-06-01
• Series: Malaria Journal
• Subjects: Malaria; <it>Plasmodium</it>; Diagnostic; Evaluation; RDT; Rapid diagnostic tests; pLDH; Lactate dehydrogenase; CareStart
• Online Access: http://www.malariajournal.com/content/11/1/204

<p>Abstract</p> <p>Background</p> <p>The present study evaluated CareStart pLDH Malaria, a three-band rapid diagnostic test detecting <it>Plasmodium falciparum-</it>specific parasite lactate dehydrogenase (Pf-pLDH) and pan <it>Plasmodium</it>-specific pLDH (pan-pLDH) in a reference setting.</p> <p>Methods</p> <p>CareStart pLDH was retrospectively and prospectively assessed with a panel of stored (n = 498) and fresh (n = 77) blood samples obtained in international travelers suspected of malaria. Both panels comprised all four <it>Plasmodium</it> species; the retrospective panel comprised also <it>Plasmodium</it> negative samples. The reference method was microscopy corrected by PCR. The prospective panel was run side-to-side with OptiMAL (Pf-pLDH/pan-pLDH) and SDFK60 (histidine-rich protein-2 (HRP-2)/pan-pLDH).</p> <p>Results</p> <p>In the retrospective evaluation, overall sensitivity for <it>P. falciparum</it> samples (n = 247) was 94.7%, reaching 98.7% for parasite densities > 1,000/μl. Most false negative results occurred among samples with pure gametocytaemia (2/12, 16.7%) and at parasite densities ≤ 100/μl (7/12, 58.3%). None of the <it>Plasmodium</it> negative samples (n = 96) showed visible test lines. Sensitivities for <it>Plasmodium vivax</it> (n = 70), <it>Plasmodium ovale</it> (n = 69) and <it>Plasmodium malariae</it> (n = 16) were 74.3%, 31.9% and 25.0% respectively. Wrong species identification occurred in 10 (2.5%) samples and was mainly due to <it>P. vivax</it> samples reacting with the Pf-pLDH test line. Overall, Pf-pLDH test lines showed higher line intensities compared to the pan-pLDH lines (67.9% and 23.0% medium and strong line intensities for <it>P. falciparum</it>). In the prospective panel (77 <it>Plasmodium</it>-positive samples), CareStart pLDH showed higher sensitivities for <it>P. falciparum</it> compared to OptiMAL (p = 0.008), lower sensitivities for <it>P. falciparum</it> as compare to SDFK60 (although not reaching statistical significance, p = 0.08) and higher sensitivities for <it>P. ovale c</it>ompared to both OptiMAL (p = 0.03) and SDFK60 (p = 0.01). Inter-observer and test reproducibility were good to excellent.</p> <p>Conclusion</p> <p>CareStart pLDH performed excellent for the detection of <it>P. falciparum,</it> well for <it>P. vivax</it>, but poor for <it>P. ovale</it> and <it>P. malariae.</it></p>