title: Molecular analysis of recrudescent parasites in a Plasmodium falciparum drug efficacy trial in Gabon.
abstract: Recrudescent Plasmodium falciparum parasites were sampled from 108 children taking part in a drug efficacy trial in Gabon. A finger-prick blood sample was taken from each child before treatment, and a post-treatment sample taken of the recrudescent parasites. Sample deoxyribonucleic acid was amplified by the polymerase chain reaction using primers specific to the P. falciparum antigen genes MSP-1, MSP-2 and GLURP. Seventy-seven children had identical parasites in their pre- and post-treatment samples, indicating genuine recrudescences of resistant parasites. Fourteen children had completely different parasites in their pre- and post-treatment samples, indicating either a fresh infection from a mosquito or growth of a population of parasites not detected in the pre-treatment sample, perhaps due to sequestration. The remaining 17 children had a mixture of pre-treatment and new parasites in their post-treatment samples. This study demonstrated the use of polymorphic markers to confirm whether parasites in patients with clinical recrudescences after drug treatment are genuinely resistant.
authors.affiliation: Institute of Cell, Animal and Population Biology, University of Edinburgh, Scotland, UK.
authors.forename: L C
authors.initials: LC
authors.lastname: Ranford-Cartwright
authors.forename: J
authors.initials: J
authors.lastname: Taylor
authors.forename: T
authors.initials: T
authors.lastname: Umasunthar
authors.forename: L H
authors.initials: LH
authors.lastname: Taylor
authors.forename: H A
authors.initials: HA
authors.lastname: Babiker
authors.forename: B
authors.initials: B
authors.lastname: Lell
authors.forename: J R
authors.initials: JR
authors.lastname: Schmidt-Ott
authors.forename: L G
authors.initials: LG
authors.lastname: Lehman
authors.forename: D
authors.initials: D
authors.lastname: Walliker
authors.forename: P G
authors.initials: PG
authors.lastname: Kremsner
mesh_terms: D000293:Adolescent; D000818:Animals; D000962:Antimalarials / Q000627:therapeutic use; D004351:Drug Resistance; D005681:Gabon; D006801:Humans; D016778:Malaria, Falciparum / Q000188:drug therapy / Q000469:parasitology*; D010963:Plasmodium falciparum / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D012008:Recurrence
chemical_list: D000962:Antimalarials