title: Diagnostic accuracy of fingerstick β-hydroxybutyrate for ketonuria in pregnant women with nausea and vomiting.
abstract: OBJECTIVE
  The aim of this study was to determine whether a rapid, fingerstick β-hydroxybutyrate (β-OHB) test predicts ketonuria in pregnant women with nausea and vomiting.
  
  
  METHODS
  A convenience sample of 82 pregnant women who presented to the Barnes-Jewish Hospital emergency department (ED) with complaints of nausea or vomiting were enrolled into an institutional review board-approved, prospective, observational study. Exclusion criteria were temperature of >38.3°C, altered mental status, prisoners, and >1 L of any intravenous (IV) fluid before screening. Subjects had fingerstick β-OHB tests, with results reported in increments of 0.1 mmol/L. Urine ketone results were made available once reported as part of standard care and varied from 0 (trace) to +4 values. Ketonuria was defined as a urine ketone value of 3+ or 4+ and was analyzed as a dichotomous, categorical variable. A contingency table and receiver operator characteristic (ROC) curve were constructed for comparing the β-OHB values to those urine ketone values for each patient.
  
  
  RESULTS
  Mean (±SD) β-OHB was 0.43 (±0.52) mmol/L, and median urine was 1+ for the cohort as a whole. The area under the ROC curve equaled 0.95. The sensitivity and specificity for a fingerstick test of >0.45 mmol/L were 89 and 94.5%, respectively. The positive likelihood ratio (LR) was 16, and the negative LR was 0.12.
  
  
  CONCLUSIONS
  Fingerstick β-OHB is a rapid and reliable diagnostic tool that correlates well with ketonuria and identifies ketonemia in pregnant women with nausea and vomiting. Fingerstick β-OHB testing has the potential to increase triage efficiency, shorten length-of-stay times, and positively affect patient outcomes in an ED setting.
authors.affiliation: Division of Emergency Medicine, Washington University School of Medicine, St. Louis, MO.
authors.forename: Ian
authors.initials: I
authors.lastname: Ferguson
authors.forename: Michael E
authors.initials: ME
authors.lastname: Mullins
mesh_terms: D020155:3-Hydroxybutyric Acid / Q000097:blood* / Q000652:urine; D000328:Adult; D005260:Female; D006801:Humans; D007662:Ketosis / Q000097:blood / Q000175:diagnosis* / Q000652:urine; D009325:Nausea / Q000175:diagnosis*; D011247:Pregnancy; D011446:Prospective Studies; D012372:ROC Curve; D012680:Sensitivity and Specificity; D014839:Vomiting / Q000175:diagnosis*
chemical_list: D020155:3-Hydroxybutyric Acid