ArticleMalaria journal2016
Low-grade sulfadoxine-pyrimethamine resistance in Plasmodium falciparum parasites from Lubango, Angola.
Article in Malaria journal, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 13 papers, 1 of them a synthesis that pooled it.
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13 citing papers in PubMed, 1 synthesis or guideline pooled it, 16 citations in OpenAlex.
- Plasmodium falciparum antimalarial resistance in Angola: a systematic review.Malaria journal · 2026Pooled it
- Molecular markers of antimalarial drug resistance in pfk13, pfmdr1, pfdhfr, and pfdhps genes of Plasmodium falciparum in a rural municipality in Cubal, Benguela Province, Angola (2022-2023).Malaria journal · 2026Article
- Assessment of genetic polymorphisms associated with malaria antifolate resistance among the population of Libreville, Gabon.Malaria journal · 2023Article
- Antimalarial Drug Resistance: A Brief History of Its Spread in Indonesia.Drug design, development and therapy · 2023Review
- Global Analysis ofMolecules (Basel, Switzerland) · 2022Article
- Molecular Determinants of Sulfadoxine-Pyrimethamine Resistance in Plasmodium falciparum Isolates from Central Africa between 2016 and 2021: Wide Geographic Spread of Highly MutatedMicrobiology spectrum · 2022Article
- Historical trends and new surveillance of Plasmodium falciparum drug resistance markers in Angola.Malaria journal · 2021Article
- Molecular surveillance of anti-malarial resistance Pfdhfr and Pfdhps polymorphisms in African and Southeast Asia Plasmodium falciparum imported parasites to Wuhan, China.Malaria journal · 2020Article
- High multiple mutations of Plasmodium falciparum-resistant genotypes to sulphadoxine-pyrimethamine in Lagos, Nigeria.Infectious diseases of poverty · 2020Article
- Trends in Molecular Markers Associated with Resistance to Sulfadoxine-Pyrimethamine (SP) AmongInfection and drug resistance · 2020Article
- Molecular Surveillance of Drug Resistance of Plasmodium falciparum Isolates Imported from Angola in Henan Province, China.Antimicrobial agents and chemotherapy · 2019Article
- High prevalence of Pfdhfr-Pfdhps quadruple mutations associated with sulfadoxine-pyrimethamine resistance in Plasmodium falciparum isolates from Bioko Island, Equatorial Guinea.Malaria journal · 2019Article
- Prevalence ofInfection and drug resistance · 2018Article
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8 authors at 3 institutions in 4 countries.
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No grant is acknowledged in the PubMed record.
Abstract
backgroundMalaria is a major parasitic disease, affecting millions of people in endemic areas. Plasmodium falciparum parasites are responsible for the most severe cases and its resistance to anti-malarial drugs is notorious. This is a possible obstacle to the effectiveness of intermittent preventive treatment (IPT) based on sulfadoxine-pyrimethamine (SP) cures administrated to pregnant women (IPTp) during their pregnancy. As this intervention is recommended in Angola since 2006, it has assessed, in this country, the molecular profiles in P. falciparum dhfr and dhps, two polymorphic genes associated to pyrimethamine and sulfadoxine resistance, respectively.
methodsBlood samples from 52 falciparum patients were collected in Lubango, Angola and pfdhfr and pfdhps polymorphisms were analysed using nested-PCR and DNA sequencing.
resultsIn the pfdhfr gene, the 108N mutation was almost fixed (98 %), followed by 59R (63 %), 51I (46 %), 50R and 164L (2 %, respectively). No 16V/S mutations were found. The most common double mutant genotype was CNRN (59 + 108; 46 %), followed by CICN (51 + 108; 29 %) whereas IRN (51 + 59 + 108; 15 %), CNRNVL (59 + 108 + 164; 2 %) and RICN (50 + 51 + 108; 2 %) triple mutant genotypes were detected. Investigations of the pfdhps gene showed that the 437G mutation was the most prevalent (97 %). Only two and one samples disclosed the 540E (7 %) and the 436A (3 %), respectively. Single mutant SGKAA (437; 86 %) was higher than SGEAA (437 + 540; 7 %) or AGKAA (436 + 437; 3 %) double mutants genotypes. No polymorphism was detected at codons 581G and 613T/S. Combining pfdhfr and pfdhps alleles two triple mutant haplotypes (double mutant in dhfr and single mutant in dhps) were observed: the ACICNVI/SGKAA in 14 (56 %) samples and the ACNRNVI/SGKAA in five (20 %) samples. One quadruple mutant haplotype was detected (ACIRNVI/SGKAA) in six (24 %) P. falciparum samples. No quintuple pfdhfr-pfdhps mutant was noted.
conclusionpfdhfr and pfdhps gene mutations in isolates from Lubango are suggestive of a low-grade SP resistance and IPT for pregnant women and infant based on SP treatment could be effective. Routine molecular studies targeting polymorphism in these two genes need to be routinely conducted at country level.
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