Artemisinin-resistant falciparum malaria — DTM&H MCQ
Instant feedback + full explanation. One question, done properly.
Educational content. Not a substitute for clinical judgement or local policy.
Reveal the answer and explanation
Correct answer: D — Triple ACT with artesunate, mefloquine, and piperaquine
The correct answer is D, triple ACT with artesunate, mefloquine, and piperaquine. The stem describes classic artemisinin partial resistance from the Greater Mekong Subregion, confirmed by a kelch13 mutation, with failure of a locally-bought antimalarial (almost certainly a standard ACT) despite two days of treatment. In this setting, standard two-drug ACTs risk failure because slow parasite clearance from artemisinin partial resistance exposes the partner drug to sub-therapeutic artemisinin cover, accelerating partner drug resistance. Combining two partner drugs (mefloquine and piperaquine) with artesunate provides genetic and pharmacological redundancy, maintaining efficacy even when resistance to one partner drug is emerging, which is the WHO-endorsed strategy for confirmed or suspected artemisinin partial resistance in this region. Why the other options are wrong: A. Artesunate monotherapy for 7 days: monotherapy with an artemisinin is never recommended as it drives further resistance selection and has a high recrudescence rate without a partner drug. C. Artemether-lumefantrine for a standard 3-day course: this is a standard ACT and is precisely the class of regimen already failing in kelch13-mutant infections from this region, so it cannot be relied upon here. E. Quinine plus tetracycline for 7 days: this regimen is poorly tolerated over a prolonged course and is reserved for situations where no ACT is available, not as first-line for confirmed resistant falciparum. B. Atovaquone-proguanil for 3 days: this is an alternative for uncomplicated malaria without resistance concerns, but atovaquone resistance can emerge quickly and it is not the recommended strategy for confirmed artemisinin partial resistance. Key point: a kelch13 mutation with treatment failure after a standard antimalarial in a Greater Mekong Subregion traveller should prompt triple ACT rather than another standard two-drug ACT.
Reference: Lalloo DG, Shingadia D, Bell DJ, et al. UK malaria treatment guidelines 2016. Journal of Infection 2016;72(6):635-649 (British Infection Association / PHE-endorsed guidance on ACT use and management of resistant falciparum malaria). https://www.sciencedirect.com/science/article/pii/S0163445316000475