Evaluation of a semiquantitative SNAP test for measurement of bile acids in dogs

Abstract

Background. Serum bile acids (SBA) are used as a routine screening tool of liver function in dogs. Serum samples are usually shipped to a referral laboratory for quantitative analysis with an enzymatic chemistry analyzer. The canine SNAP Bile Acids Test (SNAP-BAT) provides an immediate, semi-quantitative measurement of bile acid concentrations in-house. With the SNAP-BAT, bile acids concentrations of 5–30 µmol/L are quantified, and results outside of that range are classified as <5 or >30 µmol/L. Agreement of the SNAP-BAT with the enzymatic method has not been extensively investigated.Objectives. The purposes of this prospective clinical study were to assess the precision of the SNAP-BAT and determine agreement of SNAP-BAT with results from an in-house chemistry analyzer.Methods. After verifying intra-assay precision of the SNAP-BAT, a prospective analysis was performed using blood samples collected from 56 dogs suspected to have liver disease. Each sample was analyzed with an enzymatic, in-house chemistry analyzer and the SNAP-BAT. Agreement between the two methods was statistically assessed using the κ index of agreement.Results. Intra-assay variability was minimal. The κ index for agreement between the SNAP-BAT and routine chemistry analyzer was between 0.752 and 0.819, indicating substantial to near perfect agreement.Conclusions. The SNAP-BAT is a highly accurate, semi-quantitative test that yields immediate results, and has very little intra-assay variability, particularly for results >30 µmol/L.

Analytical performance and method comparison of a quantitative point-of-care immunoassay for measurement of bile acids in cats and dogs

“…The Fuji is superior to the only alternatively available POC test for BA (Snap bile acids test; Idexx), which can only quantify BA concentrations of 5–30 µmol/L. 32…”

“…The Fuji is superior to the only alternatively available POC test for BA (Snap bile acids test; Idexx), which can only quantify BA concentrations of 5-30 µmol/L. 32 The evaluation of the LLOQ was also impaired by BA concentrations <2 µmol/L. However, evaluation of serum samples with BA concentrations close to this lower detection limit showed low intra-assay CVs <4% and fulfilled quality requirements.…”

“…5 However, to our knowledge, a study has not been published on validation of the 5GA in veterinary medicine. Overall, reports about evaluation of POCAs for measurement of BA are scarce in veterinary medicine, and only a semiquantitative assay has been reported, 32 to our knowledge. We evaluated the ease of use and performance characteristics of the Fuji for detection of feline and canine total serum BA concentration compared to the 3GA and 5GA evaluated on a bench-top analyzer, with the 5GA serving as the reference method.…”