ISO‐Based Assessment of Accuracy and Precision of Glucose Meters in Dogs

Abstract

BackgroundPortable blood glucose meters (PBGMs) allow easy glucose measurements. As animal‐specific PBGMs are not available everywhere, those for humans are widely used.ObjectivesTo assess the accuracy and precision of 9 PBGMs in canine whole blood (WB) and plasma, based on the ISO 15197:2013.AnimalsFifty‐nine client‐owned dogs attending the Veterinary Teaching Hospital.MethodsAnalytical evaluation of 100 blood samples was performed for accuracy and 23 for precision (glucose 29–579 mg/dL) following ISO recommendations. A PBGM was considered accurate if 95% of the measurements were within ±15 mg/dL from the reference when glucose was <100 mg/dL and within ±15% when it was ≥100 mg/dL, and if 99% of them were within zones A and B in error grid analysis (EG). A hexokinase‐based analyzer was used as reference. Ninety samples were assessed for hematocrit interferences.ResultsAccuracy requirements were not fulfilled by any PBGM in WB (74% of measurements within the limits for the most accurate) and by 1 only in plasma. However, the EG analysis in WB was passed by 6 PBGM and by all in plasma. The most accurate were also the most precise, with coefficients of variation <5% in WB and <3% in plasma. Hematocrit correlated with bias against the reference method in 4 PBGM (r = −0.243 − [−0.371]; P < .021).Conclusions and Clinical ImportanceThis disparity among PBGM suggests that meters approved for humans need to be evaluated before use in other species.

Evaluation of portable blood glucose meters using canine and feline pooled blood samples

“…Specific PBGMs are affected by hematocrit values; anemic dogs and cats show higher WB glucose concentrations as measured by PBGMs than plasma reference glucose concentrations (Wess and Reusch 2000a,b, Mori et al 2011, Brito-Casillas et al 2014. As a result, the hematocrit clearly interfered with the results obtained by the PBGM used in the current study.…”

“…With respect to the Bland-Altman plots, most of the canine data (96% of dogs, 96% of cats) were included in the 95% limits of agreement calculated from the PBGM and the reference glucose values. However, the ISO 15197:2013 requirements are considered strict clinical indices according to previous studies (Freckmann et al 2012, Brito-Casillas et al 2014, Khositseth et al 2015. Therefore, the GLUCOCARD X-mini plus is not applicable for veterinary practice, especially in dogs and cats.…”

“…Using the above-described methods, the device accuracy can be more easily and safely evaluated using healthy canine and feline blood samples. Additionally, higher hematocrit values interfere with glucose measurement when using PBGMs (Brito-Casillas et al 2014, Domori et al 2014). Therefore, it is also necessary to evaluate whether changes in hematocrit values affect glucose values measured by the GLUCOCARD X-mini plus.…”

“…Furthermore, side effects are inevitable when taking blood samples from animals in a hypoglycemic condition. Based on the International Organization for Standardization (ISO) recommendations, if hypoglycemic or hyperglycemic blood samples from diabetic patients are unavailable, euglycemic whole blood (WB) samples should be incubated to allow for erythrocyte glycolysis or a glucose solution should be added (Brito-Casillas et al 2014;ISO 15197 2003, ISO 15197 2013. Using the above-described methods, the device accuracy can be more easily and safely evaluated using healthy canine and feline blood samples.…”

Accuracy of a flash glucose monitoring system in diabetic dogs

“…13 Simultaneously, within 1 minute from the sampling, it also scanned the FreeStyle Libre on the sensor and all data were registered.…”