Plasmodium falciparum: Evaluation of a quantitative nucleic acid sequence-based amplification assay to predict the outcome of sulfadoxine–pyrimethamine treatment of uncomplicated malaria

Omar, Sabah A.; Mens, Pètra F.; Schoone, Gerard J.; Yusuf, Andi Sitti Hajrah; Mwangi, Jonathan; Kaniaru, Stephen; Omer, G.A.A.; Schallig, Henk D. F. H.

doi:10.1016/j.exppara.2005.02.001

Cited by 15 publications

(12 citation statements)

References 19 publications

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“…In contrast, PCR was positive in three out of the six samples, two of the donors of which developed relapses. In parallel, Omar et al (16) demonstrated that QT-NASBA can predict antimalarial treatment failures.…”

Section: Discussionmentioning

confidence: 98%

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Quantitative Nucleic Acid Sequence-Based Assay as a New Molecular Tool for Detection and Quantification of Leishmania Parasites in Skin Biopsy Samples

et al. 2005

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Currently available methods for the diagnosis of cutaneous leishmaniasis (CL) have low sensitivities or are unable to quantify the number of viable parasites. This constitutes a major obstacle for the diagnosis of the disease and for the study of the effectiveness of treatment schedules and urges the development of improved detection methods. In this study, quantitative nucleic acid sequence-based amplification (QT-NASBA) technology was used to detect and quantify Leishmania parasites in skin biopsy samples from CL patients. The assay is based on the detection of a small subunit rRNA (18S rRNA), which may allow for the detection of viable parasites. The QT-NASBA assay was evaluated using in vitro-cultured promastigotes and amastigotes and 2-mm skin biopsy samples from Old and New World CL patients. The study demonstrated that the lower detection limit of the QT-NASBA was two parasites per biopsy sample. Parasites could be quantified in a range of 2 to 11,300,000 parasites per biopsy sample. The QT-NASBA could detect levels of parasites 100-fold lower than those detected by conventional PCR. Test evaluation revealed that the QT-NASBA had a sensitivity of 97.5% and a specificity of 100% in the present study. The QT-NASBA is a highly sensitive and specific method that allows quantification of both Old and New World Leishmania parasites in skin biopsy samples and may provide an important tool for diagnosis as well as for monitoring the therapy of CL patients.

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Section: Discussionmentioning

confidence: 98%

“…Moreover, the detection of specific RNA molecules may serve as a suitable marker for pathogen viability (26,29). The QT-NASBA assay already has been successfully applied in studies to assess the efficacy of drug therapies for Plasmodium falciparum infection and to predict treatment outcomes (16,19).…”

mentioning

confidence: 99%

Quantitative Nucleic Acid Sequence-Based Assay as a New Molecular Tool for Detection and Quantification of Leishmania Parasites in Skin Biopsy Samples

et al. 2005

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“…Three targets that show high specificity for ring-stage trophozoites, and have only low levels of transcripts in mature gametocytes, all indicate persisting transcripts until day 14 postinitiation of treatment. Our duration of follow-up was chosen to inform the gametocytocidal properties of the different antimalarials 15 and was too short to determine whether the persistence of trophozoite-specific transcripts was associated with subsequent recrudescence of infections, 45 de novo production of gametocytes or enhanced transmission potential 27 . Our study has demonstrated the strength and weaknesses of several asexual parasite targets for epidemiological and clinical studies.…”

Section: Discussionmentioning

confidence: 99%

Molecular Markers for Sensitive Detection of Plasmodium falciparum Asexual Stage Parasites and their Application in a Malaria Clinical Trial

Tadesse

Lanke

Nébié

et al. 2017

The American Society of Tropical Medicine and Hygiene

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Abstract.Plasmodium falciparum parasite life stages respond differently to antimalarial drugs. Sensitive stage-specific molecular assays may help to examine parasite dynamics at microscopically detectable and submicroscopic parasite densities in epidemiological and clinical studies. In this study, we compared the performance of skeleton-binding protein 1 (SBP1), ring-infected erythrocyte surface antigen, Hyp8, ring-exported protein 1 (REX1), and PHISTb mRNA for detecting ring-stage trophozoite-specific transcripts using quantitative reverse transcriptase polymerase chain reaction. Markers were tested on tightly synchronized in vitro parasites and clinical trial samples alongside established markers of parasite density (18S DNA and rRNA) and gametocyte density (Pfs25 mRNA). SBP1 was the most sensitive marker but showed low-level expression in mature gametocytes. Novel markers REX1 and PHISTb showed lower sensitivity but higher specificity for ring-stage trophozoites. Using in vivo clinical trial samples from gametocyte-negative patients, we observed evidence of persisting trophozoite transcripts for at least 14 days postinitiation of treatment. It is currently not clear if these transcripts represent viable parasites that may have implications for clinical treatment outcome or transmission potential.

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“…The second way in which were summariszd the data, was to calculate the proportion of all infections (mixed and non-mixed), which were found to contain all three dhfr mutations plus the dhps 437 and 540 mutations. This particular genotype has been shown to be associated with SP treatment failure in a number of East African countries: Kenya, Malawi and Uganda but has only been reported rarely in West Africa [11-13]. …”

Section: Methodsmentioning

confidence: 99%

Efficacy of antimalarial treatment in Guinea: in vivo study of two artemisinin combination therapies in Dabola and molecular markers of resistance to sulphadoxine-pyrimethamine in N'Zérékoré

Bonnet¹,

Roper

Félix

et al. 2007

Malar J

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Background: In the last five years, countries have been faced with changing their malaria treatment policy to an artemisinin-based combination therapy (ACT), many with no national data on which to base their decision. This is particularly true for a number of West African countries, including Guinea, where these studies were performed. Two studies were conducted in 2004/2005 in programmes supported by Medecins Sans Frontieres, when chloroquine was still national policy, but artesunate (AS)/sulphadoxine-pyrimethamine (SP) had been used in refugee camps for two years.

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Plasmodium falciparum: Evaluation of a quantitative nucleic acid sequence-based amplification assay to predict the outcome of sulfadoxine–pyrimethamine treatment of uncomplicated malaria

Cited by 15 publications

References 19 publications

Quantitative Nucleic Acid Sequence-Based Assay as a New Molecular Tool for Detection and Quantification of Leishmania Parasites in Skin Biopsy Samples

Quantitative Nucleic Acid Sequence-Based Assay as a New Molecular Tool for Detection and Quantification of Leishmania Parasites in Skin Biopsy Samples

Molecular Markers for Sensitive Detection of Plasmodium falciparum Asexual Stage Parasites and their Application in a Malaria Clinical Trial

Efficacy of antimalarial treatment in Guinea: in vivo study of two artemisinin combination therapies in Dabola and molecular markers of resistance to sulphadoxine-pyrimethamine in N'Zérékoré

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