title: Diagnostic accuracy of point-of-care testing for diabetic ketoacidosis at emergency-department triage: {beta}-hydroxybutyrate versus the urine dipstick.
abstract: OBJECTIVE
  In the emergency department, hyperglycemic patients are screened for diabetic ketoacidosis (DKA) via a urine dipstick. In this prospective study, we compared the test characteristics of point-of-care β-hydroxybutyrate (β-OHB) analysis with the urine dipstick.
  
  
  METHODS
  Emergency-department patients with blood glucose ≥250 mg/dL had urine dipstick, chemistry panel, venous blood gas, and capillary β-OHB measurements. DKA was diagnosed according to American Diabetes Association criteria.
  
  
  RESULTS
  Of 516 hyperglycemic subjects, 54 had DKA. The urine dipstick had a sensitivity of 98.1% (95% CI 90.1-100), a specificity of 35.1% (30.7-39.6), a positive predictive value of 15% (11.5-19.2), and a negative predictive value of 99.4% (96.6-100) for DKA. Using the manufacturer-suggested cutoff of >1.5 mmol/L, β-OHB had a sensitivity of 98.1% (90.1-100), a specificity of 78.6% (74.5-82.2), a positive predictive value of 34.9% (27.3-43), and a negative predictive value of 99.7% (98.5-100) for DKA.
  
  
  CONCLUSIONS
  Point-of-care β-OHB and the urine dipstick are equally sensitive for detecting DKA (98.1%). However, β-OHB is more specific (78.6 vs. 35.1%), offering the potential to significantly reduce unnecessary DKA work-ups among hyperglycemic patients in the emergency department.
authors.affiliation: Department of Clinical Emergency Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA. sanjay.arora@usc.edu
authors.forename: Sanjay
authors.initials: S
authors.lastname: Arora
authors.forename: Sean O
authors.initials: SO
authors.lastname: Henderson
authors.forename: Theodore
authors.initials: T
authors.lastname: Long
authors.forename: Michael
authors.initials: M
authors.lastname: Menchine
mesh_terms: D020155:3-Hydroxybutyric Acid; D000328:Adult; D016883:Diabetic Ketoacidosis / Q000175:diagnosis* / Q000652:urine; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D019095:Point-of-Care Systems / Q000706:statistics & numerical data*; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014218:Triage / Q000379:methods*
chemical_list: D020155:3-Hydroxybutyric Acid