Differentiation between Trypanosoma cruzi and Trypanosoma rangeli using heat‐shock protein 70 polymorphisms. Issue 2 (13th November 2013)

• Record Type: Journal Article
• Authors: Fraga, Jorge; Fernandez‐Calienes, Aymé; Montalvo, Ana Margarita; Maes, Ilse; Dujardin, Jean‐Claude; Van der, Gert
• Is Part Of: Tropical medicine & international health. Volume 19:Issue 2(2014:Feb.)
• Page Start: 195
• Page End: 206
• Publication Date: 2013-11-13
• Subjects: Tropical medicine -- Periodicals; Public health -- Periodicals; 616.988
• DOI: 10.1111/tmi.12222
• Languages: English
• ISSNs: 1360-2276

Abstract

<abstract abstract-type="main" id="tmi12222-abs-0001"> <title>Abstract</title> <sec id="tmi12222-sec-0001" sec-type="section"> <title>Objective</title> <p>Differential diagnosis of infection with <italic>Trypanosoma cruzi</italic> or <italic>T. rangeli</italic> is relevant for epidemiological studies and clinical practice as both species infect humans, but only <italic>T. cruzi</italic> causes Chagas' disease. Their common antigen determinants complicate the distinction between both species, while current PCR assays used for differentiation show some drawbacks. We developed and validated a generic PCR discriminating the species by restriction fragment length polymorphism (RFLP) analysis and a duplex PCR specifically amplifying a differently sized fragment of both species.</p> </sec> <sec id="tmi12222-sec-0002" sec-type="section"> <title>Methods</title> <p>The assays are based upon a partial region of the heat‐shock protein 70 gene (<italic>hsp</italic>70). The analytical sensitivity and specificity were determined for both PCRs. The assays were analytically evaluated on a panel of six <italic>T. cruzi</italic>, one <italic>T. cruzi marinkellei</italic> and four <italic>T. rangeli</italic> strains, various other infectious pathogens, a panel of spiked samples of <italic>T. cruzi</italic>, and artificially mixed infections of <italic>T. cruzi</italic> and <italic>T. rangeli</italic>. Finally, the tools were applied on 36 additional isolates of <italic>Trypanosoma</italic> species.</p> </sec> <sec id="tmi12222-sec-0003" sec-type="section"> <title>Results</title> <p>The detection limit of the PCRs was between 0.05 and 0.5 parasite genomes, and 1–10 parasites spiked in 200 μl blood. In artificial mixtures, PCR–RFLP picked up both species in ratios up to 10<sup>2</sup> and duplex PCR up to 10<sup>4</sup>. In the 36 isolates tested, both single and mixed infections were identified. All assays were shown to be specific.</p> </sec> <sec id="tmi12222-sec-0004" sec-type="section"> <title>Conclusion</title> <p>Our PCRs show high potential for the differential diagnosis of <italic>T. cruzi</italic> and <italic>T. rangeli</italic>, which in view of their sensitivity can aid in the confirmation of infection with these parasites in vectors, reservoirs and clinical samples.</p> </sec> </abstract>