Ex vivo piperaquine resistance developed rapidly in Plasmodium falciparum isolates in northern Cambodia compared to Thailand
| Autor: | Somethy Sok, Krisada Jongsakul, Chanthap Lon, Nareth Kong, Rekol Huy, Charlotte A. Lanteri, Suwanna Chaorattanakawee, Sorayut Chattrakarn, Jariyanart Gawee, Douglas S. Walsh, Nichapat Uthaimongkol, Soklyda Chann, Philip A. Smith, David L. Saunders, Delia Bethell, Siratchana Sundrakes, Narongrid Sirisopana, Satharath Prom, Nillawan Buathong, Chatchadaporn Thamnurak, Chantida Praditpol, Mark M. Fukuda |
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| Jazyk: | angličtina |
| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
Veterinary medicine lcsh:Arctic medicine. Tropical medicine lcsh:RC955-962 030106 microbiology Plasmodium falciparum Drug Resistance Protozoan Proteins Antigens Protozoan Drug resistance lcsh:Infectious and parasitic diseases 03 medical and health sciences chemistry.chemical_compound Antimalarials Inhibitory Concentration 50 Parasitic Sensitivity Tests Piperaquine parasitic diseases medicine Humans lcsh:RC109-216 Artemisinin biology Mefloquine Research biology.organism_classification medicine.disease Thailand Artemisinins Malaria Infectious Diseases Parasitology chemistry Artesunate Quinolines Cambodia medicine.drug |
| Zdroj: | Malaria Journal Malaria Journal, Vol 15, Iss 1, Pp 1-12 (2016) |
| ISSN: | 1475-2875 |
| Popis: | Background The recent dramatic decline in dihydroartemisinin-piperaquine (DHA-PPQ) efficacy in northwestern Cambodia has raised concerns about the rapid spread of piperaquine resistance just as DHA-PPQ is being introduced as first-line therapy in neighbouring countries. Methods Ex vivo parasite susceptibilities were tracked to determine the rate of progression of DHA, PPQ and mefloquine (MQ) resistance from sentinel sites on the Thai–Cambodian and Thai–Myanmar borders from 2010 to 2015. Immediate ex vivo (IEV) histidine-rich protein 2 (HRP-2) assays were used on fresh patient Plasmodium falciparum isolates to determine drug susceptibility profiles. Results IEV HRP-2 assays detected the precipitous emergence of PPQ resistance in Cambodia beginning in 2013 when 40 % of isolates had an IC90 greater than the upper limit of prior years, and this rate doubled to 80 % by 2015. In contrast, Thai–Myanmar isolates from 2013 to 14 remained PPQ-sensitive, while northeastern Thai isolates appeared to have an intermediate resistance profile. The opposite trend was observed for MQ where Cambodian isolates appeared to have a modest increase in overall sensitivity during the same period, with IC50 declining to median levels comparable to those found in Thailand. A significant association between increased PPQ IC50 and IC90 among Cambodian isolates with DHA-PPQ treatment failure was observed. Nearly all Cambodian and Thai isolates were deemed artemisinin resistant with a >1 % survival rate for DHA in the ring-stage assay (RSA), though there was no correlation among isolates to indicate cross-resistance between PPQ and artemisinins. Conclusions Clinical DHA-PPQ failures appear to be associated with declines in the long-acting partner drug PPQ, though sensitivity appears to remain largely intact for now in western Thailand. Rapid progression of PPQ resistance associated with DHA-PPQ treatment failures in northern Cambodia limits drugs of choice in this region, and urgently requires alternative therapy. The temporary re-introduction of artesunate AS-MQ is the current response to PPQ resistance in this area, due to inverse MQ and PPQ resistance patterns. This will require careful monitoring for re-emergence of MQ resistance, and possible simultaneous resistance to all three drugs (AS, MQ and PPQ). Electronic supplementary material The online version of this article (doi:10.1186/s12936-016-1569-y) contains supplementary material, which is available to authorized users. |
| Databáze: | OpenAIRE |
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