title: Prevalence of in vitro resistance to eleven standard or new antimalarial drugs among Plasmodium falciparum isolates from Pointe-Noire, Republic of the Congo.
abstract: We determined the level of in vitro resistance of Plasmodium falciparum parasites to standard antimalarial drugs, such as chloroquine, quinine, amodiaquine, halofantrine, mefloquine, cycloguanil, and pyrimethamine, and to new compounds, such as dihydroartemisinin, doxycycline, atovaquone, and lumefantrine. The in vitro resistance to chloroquine reached 75.5%. Twenty-eight percent of the isolates were intermediate or had reduced susceptibility to quinine. Seventy-six percent and 96% of the tested isolates showed in vitro resistance or intermediate susceptibilities to cycloguanil and pyrimethamine, respectively. Only 2% of the parasites demonstrated in vitro resistance to monodesethylamodiaquine. No resistance was shown with halofantrine, lumefantrine, dihydroartemisinin, or atovaquone. Halofantrine, mefloquine, and lumefantrine demonstrated high correlation. No cross-resistance was identified between responses to monodesethyl-amodiaquine, dihydroartemisinin, atovaquone, and cycloguanil. Since the level of chloroquine resistance in vitro exceed an unacceptable upper limit, high rates of in vitro resistance to pyrimethamine and cycloguanil and diminution of the susceptibility to quinine, antimalarial drugs used in combination, such as amodiaquine, artemisinin derivatives, mefloquine, lumefantrine, or atovaquone, seem to be appropriate alternatives for the first line of treatment of acute, uncomplicated P. falciparum malaria.
authors.affiliation: IMTSSA, URBEP, Bd. C. Livon, Parc le Pharo, BP 46, 13998 Marseille Armées, France. bruno.pradines@free.fr
authors.forename: Bruno
authors.initials: B
authors.lastname: Pradines
authors.forename: Philippe
authors.initials: P
authors.lastname: Hovette
authors.forename: Thierry
authors.initials: T
authors.lastname: Fusai
authors.forename: Henri Léonard
authors.initials: HL
authors.lastname: Atanda
authors.forename: Eric
authors.initials: E
authors.lastname: Baret
authors.forename: Philippe
authors.initials: P
authors.lastname: Cheval
authors.forename: Joel
authors.initials: J
authors.lastname: Mosnier
authors.forename: Alain
authors.initials: A
authors.lastname: Callec
authors.forename: Julien
authors.initials: J
authors.lastname: Cren
authors.forename: Rémy
authors.initials: R
authors.lastname: Amalvict
authors.forename: Jean Pierre
authors.initials: JP
authors.lastname: Gardair
authors.forename: Christophe
authors.initials: C
authors.lastname: Rogier
mesh_terms: D000293:Adolescent; D000818:Animals; D000962:Antimalarials / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D003223:Congo; D004351:Drug Resistance; D006801:Humans; D007223:Infant; D016778:Malaria, Falciparum / Q000469:parasitology; D021261:Parasitic Sensitivity Tests; D010963:Plasmodium falciparum / Q000187:drug effects* / Q000302:isolation & purification; D013223:Statistics as Topic
chemical_list: D000962:Antimalarials