Evaluation of two point-of-care ethylene glycol tests for dogs

Objective - To evaluate 2 point-of-care ethylene glycol (EG) tests in dogs. Design - Prospective, randomized, blinded laboratory evaluation. Setting - University teaching hospital. Animals - Ten healthy adult dogs. Interventions - Jugular venipuncture and in vitro evaluation for detection of EG in canine blood. Measurements - Whole blood samples were centrifuged and separated, and the plasma was divided into 30 aliquots. The aliquots were mixed with EG to provide EG concentrations ranging from 0 to 100 mg/dL. The EG concentration of each sample was confirmed using gas chromatography. For the VetSpec EG Qualitative Reagent Test Kit, 100 mu L of each sample was added to test vials and compared with 20 and 50 mg/dL reference vials. For the Kacey EG Test Strips, 20 mu L of each sample was added to the test circle and compared with the color chart provided by the manufacturer. For each test, samples were prepared in groups of 5 and presented in randomized order to 2 readers who were blinded to the presumed EG concentration. Samples were scored as negative, 20-50 mg/dL, or greater than 50 mg/dL. For each test, the sensitivity and specificity for detecting EG was calculated. Cohen's unweighted kappa coefficient was calculated to determine the degree of agreement between readers. Main Results - For detecting EG, the Kacey EG Test Strips had excellent sensitivity and specificity (both 100%) and good agreement between readers. The VetSpec EG Qualitative Reagent Test Kit was less sensitive and specific (65% and 70% for the first reader, 95% and 40% for the second) with less agreement. Conclusions - Of the 2 systems evaluated, the Kacey EG Test Strips displayed greater accuracy and ease of use.