Residual antimalarial concentrations before treatment in patients with malaria from Cambodia: indication of drug pressure.
BACKGROUND
The Thai-Cambodian border has been known as the origin of antimalarial drug resistance for the past 30 years. There is a highly diverse market for antimalarials in this area, and improved knowledge of drug pressure would be useful to target interventions aimed at reducing inappropriate drug use.


METHODS
Baseline samples from 125 patients with falciparum malaria recruited for 2 in vivo studies (in Preah Vihear and Pursat provinces) were analyzed for the presence of 14 antimalarials in a single run, by means of a liquid chromatography-tandem mass spectrometry assay.


RESULTS
Half of the patients had residual drug concentrations above the lower limit of calibration for at least 1 antimalarial at admission. Among the drugs detected were the currently used first-line drugs mefloquine (25% and 35% of patients) and piperaquine (15% of patients); the first-line drug against vivax malaria, chloroquine (25% and 41% of patients); and the former first-line drug, quinine (5% and 34% patients).


CONCLUSIONS
The findings demonstrate that there is high drug pressure and that many people still seek treatment in the private and informal sector, where appropriate treatment is not guaranteed. Promotion of comprehensive behavioral change, communication, community-based mobilization, and advocacy are vital to contain the emergence and spread of parasite resistance against new antimalarials.
Hodel
Eva Maria
EM
Swiss Tropical Institute, Basel, Switzerland.
Genton
Blaise
B
Zanolari
Boris
B
Mercier
Thomas
T
Duong
Socheat
S
Beck
Hans-Peter
HP
Olliaro
Piero
P
Decosterd
Laurent Arthur
LA
Ariey
Frédéric
F
D000293:Adolescent; D000328:Adult; D000962:Antimalarials / Q000097:blood*; D002160:Cambodia; D002648:Child; D002675:Child, Preschool; D002738:Chloroquine / Q000097:blood; D002853:Chromatography, Liquid; D004351:Drug Resistance; D005260:Female; D006801:Humans; D016778:Malaria, Falciparum / Q000175:diagnosis*; D008297:Male; D015767:Mefloquine / Q000097:blood; D008875:Middle Aged; D011803:Quinine / Q000097:blood; D011804:Quinolines / Q000097:blood; D012641:Selection, Genetic; D044967:Serum / Q000737:chemistry*; D053719:Tandem Mass Spectrometry; D055815:Young Adult; D010879:Piperazines
D000962:Antimalarials; D002738:Chloroquine; D015767:Mefloquine; D011803:Quinine; D011804:Quinolines; C034759:piperaquine; D010879:Piperazines