title: Responses of multidrug-resistant Plasmodium falciparum parasites to mefloquine in Nigerian children.
abstract: Thirty-three children aged 6 months to 7 years from an area with multidrug-resistant Plasmodium falciparum strains were treated with 25 mg/kg body weight of mefloquine base as a single oral dose. They were followed-up using the modified 28-day WHO extended field test. The parasite isolates from these patients were cultured in vitro with different concentrations of mefloquine. All children were parasite-negative by day 4, and 31 remained so throughout the period of observation. Two patients who were parasitaemic on days 16 and 28 were successfully treated with a sulphadoxine/pyrimethamine combination. Parasitological and clinical responses were well correlated. The mean parasite clearance time was 65 +/- 10.2 hours. A mefloquine concentration of 64 pmol/well inhibited schizont growth and the EC50 and EC99 were 5.5 and 5.4 pmol/well (1.1 and 10.8 mumol/l blood) respectively. This indicates reduced parasite susceptibility to the drug in vitro.
authors.affiliation: Department of Pharmacology and Clinical Pharmacy, Ahmadu Bello University, Zaria, Nigeria.
authors.forename: J N
authors.initials: JN
authors.lastname: Okoyeh
authors.forename: L
authors.initials: L
authors.lastname: Lege-Oguntoye
authors.forename: R O
authors.initials: RO
authors.lastname: Ugbode
authors.forename: G O
authors.initials: GO
authors.lastname: Ogunrinde
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000627:therapeutic use; D000962:Antimalarials / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D004352:Drug Resistance, Microbial; D018432:Drug Resistance, Multiple; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D007223:Infant; D016778:Malaria, Falciparum / Q000188:drug therapy*; D008297:Male; D015767:Mefloquine / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D008826:Microbial Sensitivity Tests; D009549:Nigeria; D018512:Parasitemia / Q000175:diagnosis / Q000188:drug therapy; D010963:Plasmodium falciparum / Q000187:drug effects; D011739:Pyrimethamine / Q000627:therapeutic use; D013413:Sulfadoxine / Q000627:therapeutic use
chemical_list: D000890:Anti-Infective Agents; D000962:Antimalarials; D013413:Sulfadoxine; D015767:Mefloquine; D011739:Pyrimethamine