title: Chloroquine resistance of Plasmodium falciparum in Brazil detected by a simple in vitro method.
abstract: The sensitivity of Plasmodium falciparum to antimalarial drugs is primarily determined by observing changes in the level of parasitaemia after administration of drugs to man. Performance of such a study and interpretation of its results may present certain difficulties, especially when conducted among persons living in malarious areas. The present study was conducted to evaluate the usefulness of a simple in vitro method for detecting chloroquine-resistant strains among infected residents of Mato Grosso, Brazil. The findings indicated the participants were infected with chloroquine-resistant P. falciparum. Subsequent administration of a standard regimen of chloroquine (25 mg/kg) to these subjects confirmed the findings observed in vitro by failing to cure 28 out of 30 infections. This in vitro technique seems to provide a useful method of determining the presence or prevalence of chloroquine-resistant strains in a given area.
mesh_terms: D001938:Brazil; D002738:Chloroquine / Q000008:administration & dosage / Q000494:pharmacology*; D004352:Drug Resistance, Microbial; D006801:Humans; D008288:Malaria / Q000188:drug therapy; D008722:Methods; D008826:Microbial Sensitivity Tests; D010963:Plasmodium falciparum / Q000187:drug effects*
chemical_list: D002738:Chloroquine