But similar to the V-BTA measurement, the S100A8/A9USG in dogs ≥6 years of age also suffers from a moderate rate of false positives (59% for dogs with a UTI and 24% [18–33%] for the remaining groups of dogs when using a cut-off of ≥109.9), which is also consistent with the increased urinary proteome fraction of S100A8/A9 and S100A12 (i.e., S100A8/A9Prot and S100A12Prot) in TCC/PCA dogs with concurrent UTI. This evidence concerns the gene S100A8 and bacterial urinary tract infection.