Urine albumin/creatinine ratio measurement improves urinalysis protocols in obstetric day units currently failing to identify women with pre-eclampsia

Abstract

Most obstetric day unit (ODU) protocols to assess pre-eclampsia include dipstick urinalysis of a fresh midstream urine. It is the view of obstetricians that this urine sample is more accurate with lower false positive negative values and only if this urine sample is positive on dipstick urinalysis is a 24-hour urine collection undertaken. One hundred and seventy-one women referred to the ODU were recruited. A fresh urine sample was tested with both visual and automated dipsticks and for albumin/creatinine ratio (ACR) on a validated urinalyser. All patients then collected a 24-hour total protein sample. Sensitivity and specificity are tested for significance with the χ² test. Table 1 shows the results for the prediction of 300 mg protein/24 hours at the 1+ threshold. ACR testing, which corrects for fluctuations in urine concentration, offers significant improvements over all other testing strategies.