Protein/creatinine ratio urine dipsticks significantly improve the detection of true proteinuria and hence pre-eclampsia

Abstract

Conventional dipstick urinalysis has high false-positive and false-negative rates and this can lead to unnecessary hospital admission or pre-eclampsia being missed. Urine protein/creatinine ratio correlates well with 24-hour protein excretion but still takes up to 24 hours for laboratory results. We describe the first assessment of a protein/creatinine ratio dipstick (Multistix PRO: Bayer Diagnostics). A total of 171 hypertensive women were recruited. An MSU was tested with visual and automated dipsticks and for protein/creatinine ratio (PCR) on a validated urinalyser (Clinitek 50: Bayer Diagnostics). All had 24-hour total protein measured in the laboratory. Sensitivity and specificity are compared with the χ² test for PCR dipsticks vs. other urinalysis tests. Table 1 shows the results for the prediction of 300mg protein/24 hours at the 1+ threshold. Five samples using the PCR dipstick were too dilute too assess proteinuria and were identified as needing repeat samples.