Liz Buchanan BVSc MRCVS
Gosh - it's pretty unusual for a high blood sugar not to be causing clinical signs, and very timely that your staffy had the test when she did. Diabetes happens because you need a chemical called insulin to use the sugar in your diet. 'Sugar' comes from any carbohydrates - they are all broken down into a sugar called glucose - and insulin is needed to usefully move that glucose from the blood, into the body-cells, where it is turned to energy. Diabetics don't make insulin, so the sugar can't get into the body-cells and turn into energy. These dogs end up with high levels of sugar in the blood, that can't get into the cells to be used. This means that they lose weight (you need to absorb sugar in your cells to put weight on), feel excessively thirsty (high sugar in the veins affects the kidneys, making the patient wee more and feel more thirsty), and very hungry (because all the energy they're eating just isn't getting absorbed, so they want to eat more). It doesn't sound as though your dog is showing these signs, or if they are, then the symptoms are not yet causing a problem. Your vet must therefore be keen to check that your dog is genuinely diabetic, which must be why they have asked to repeat the tests. There are some differential (alternative) diagnoses for high blood sugar, such as some obscure kidney diseases e.g. renal glucosuria, Fanconi syndrome , perhaps some dietary indiscretions (such as consuming very highly sugary substance just before the test), and perhaps some rare lab-testing errors too. Giving Insulin where blood sugar is not high, can lead to some horrid side-effects, so I think that your vet is right to monitor things very carefully while they figure out what is going on. They might decide to consult pathologists or canine diabetes experts on the subject, but the main thing for now is that you know the signs of diabetes and if your dog becomes lethargic, starts drinking excessively or if you smell pear-drops on her breath, then do contact your vet right away.