Prospective Comparison of Catheterized and Clean Catch Urine Specimens for Determination of Protein/Creatinine Ratio in Evaluation of Preeclampsia

Preeclampsia is the new onset of hypertension and proteinuria after twenty weeks of gestation in pregnant women. The gold standard for evaluation of proteinuria in the diagnosis of preeclampsia is a twenty-four hour urine collection. However, single-specimen protein/creatinine ratios have been used to detect preeclampsia without the delay and inconvenience that a twenty-four hour urine collection would entail. At our institution, women are routinely catheterized for urine collection of protein/creatinine ratios because of concerns that vaginal contaminants would falsely elevate protein measurement in urine. However, no studies have specifically evaluated whether catheterized urine specimens correlate to clean catch urine specimens in protein estimation. Thus, the purpose of this prospective study was to examine whether protein/creatinine ratios in catheterized urine specimens correlate to clean catch specimens in pregnant patients being evaluated for preeclampsia.