title: Diagnostic utility of urine protein-to-creatinine ratio for identifying proteinuria in pregnancy.
abstract: OBJECTIVE
  To evaluate urine protein-to-creatinine ratio (UPC) alone and with uric acid and clinical factors to predict or exclude significant proteinuria in preeclampsia evaluations.
  
  
  METHODS
  Retrospective cohort study patients undergoing evaluation for preeclampsia. Greater than 300 mg of protein in a 24-h collection was the gold standard defining proteinuria against which UPC performance was measured. Bivariable, multivariable, and Receiver Operating Characteristic Curve (ROC) analyses were performed. Sensitivity, specificity, predictive values, and likelihood ratios were calculated for multiple cut-points of UPC alone and with uric acid.
  
  
  RESULTS
  In a cohort of 356 patients, the area under the curve for UPC in the diagnosis of proteinuria was 0.81. No single cut-point of UPC was diagnostic of preeclampsia. UPC values ≤0.08 or ≥1.19 have useful negative or positive predictive values of 86% and 96%. Uric acid and clinical factors did not improve the detection of significant proteinuria.
  
  
  CONCLUSIONS
  Extreme values of UPC ratio ≤0.08 or ≥1.19 have favorable predictive values, which could enable the rapid diagnosis of preeclampsia without a 24-h urine collection.
authors.affiliation: Department of Obstetrics and Gynecology, Washington University School of Medicine, St Louis, MO, USA. stoutm@wustl.edu
authors.forename: Molly J
authors.initials: MJ
authors.lastname: Stout
authors.forename: Christina M
authors.initials: CM
authors.lastname: Scifres
authors.forename: David M
authors.initials: DM
authors.lastname: Stamilio
mesh_terms: D000328:Adult; D003404:Creatinine / Q000652:urine; D005260:Female; D006801:Humans; D011225:Pre-Eclampsia / Q000175:diagnosis* / Q000652:urine*; D011247:Pregnancy; D011507:Proteinuria / Q000175:diagnosis* / Q000652:urine; D012372:ROC Curve; D012189:Retrospective Studies
chemical_list: D003404:Creatinine