title: Quinine with tetracycline for the treatment of drug-resistant falciparum malaria in Thailand.
abstract: Reports of deteriorating quinine efficacy prompted us to investigate the ability of quinine-tetracycline to clear parasites and fever from patients with multiple drug-resistant Plasmodium falciparum infections. Past and present treatment results were compared at two study sites along the Thai-Cambodian border. In northeastern Thailand, quinine-tetracycline cleared parasites more quickly in 1990 than in 1987 (mean 3.4 and 4.0 days, respectively; P = 0.006). In southeastern Thailand, there were no significant differences between 1990 (n = 26) and 1981-1983 (n = 42) in the time taken to clear either parasites (median 96 and 93 hr, respectively; P = 0.35) or fever (mean 74 and 66 hr, respectively; P = 0.30). In vitro drug sensitivity testing revealed a two-fold decrease in susceptibility to quinine between 1983 and 1990 in isolates from the southeastern Thai-Cambodian border (mean inhibitory concentration 166 ng/ml and 320 ng/ml, respectively; P less than 0.001). We conclude that oral quinine-tetracycline continues to reliably clear parasites and fever from falciparum malaria patients infected in eastern Thailand. Periodic re-evaluations are warranted, however, since the decrease in vitro susceptibility to quinine may be followed by an in vivo decay in the treatment response.
authors.affiliation: Armed Forces Research Institute of Medical Science, Bangkok, Thailand.
authors.forename: G
authors.initials: G
authors.lastname: Watt
authors.forename: L
authors.initials: L
authors.lastname: Loesuttivibool
authors.forename: G D
authors.initials: GD
authors.lastname: Shanks
authors.forename: E F
authors.initials: EF
authors.lastname: Boudreau
authors.forename: A E
authors.initials: AE
authors.lastname: Brown
authors.forename: K
authors.initials: K
authors.lastname: Pavanand
authors.forename: H K
authors.initials: HK
authors.lastname: Webster
authors.forename: S
authors.initials: S
authors.lastname: Wechgritaya
mesh_terms: D000328:Adult; D000818:Animals; D004351:Drug Resistance; D004359:Drug Therapy, Combination; D006801:Humans; D016778:Malaria, Falciparum / Q000188:drug therapy*; D008297:Male; D008889:Military Personnel; D010963:Plasmodium falciparum / Q000187:drug effects*; D011446:Prospective Studies; D011803:Quinine / Q000494:pharmacology / Q000627:therapeutic use*; D013752:Tetracycline / Q000494:pharmacology / Q000627:therapeutic use*; D013785:Thailand
chemical_list: D011803:Quinine; D013752:Tetracycline