Evaluation of test sensitivity and test specificity of three field methods for quantification of chloroquine in urine using liquid chromatography as reference method.
We have evaluated three quantitative colorimetric methods [bromthymol blue (BTB), Haskins, and Saker-Salomons (S-S)] for measurement of concentrations of chloroquine (CQ) in urine. A graphical evaluation of test sensitivity and test specificity at different concentrations of CQ in authentic urine samples was used. Liquid chromatography (LC) was used as a reference method. The Haskins method showed the highest test specificity (89%) and test sensitivity (97%), at a discrimination value of 2 mumols/L. At the same sensitivity (97%) as the Haskins method, S-S and BTB methods had test specificities of 49 and 13%, respectively. The correlation coefficients between the LC method and the colorimetric methods were all higher than 0.94 at a urinary concentration range of 2-100 mumols/L. The intra- and interassay variations for the colorimetric methods were all uniformly less than 15% at 2 mumols/L, but the Haskins method showed less variation than the other two methods.
Bergqvist
Y
Y
Department of Clinical Chemistry, Falun Central Hospital, Sweden.
Eckerbom
S
S
Gerhardt
W
W
Rombo
L
L
D002648:Child; D002738:Chloroquine / Q000652:urine*; D002853:Chromatography, Liquid / Q000379:methods; D003124:Colorimetry / Q000379:methods; D003429:Cross Reactions; D005069:Evaluation Studies as Topic; D006801:Humans; D012016:Reference Values
D002738:Chloroquine