CBC / WBC and blood chemistry values including a blood glucose screen for diabetes (dog)(cat), cholesterol level, Thyroid panel for hypothyroidism (free T - 4), ACTH stimulation test or low dose dexamethasone suppression tests for Cushing's disease, TLI, cPL ® or fPL ® for Pancreatitis, fructosamine test for diabetes, urinalysis including protein: creatinine ratio, microalbuminuria test (2ndchance.info)
The other is an overnight dexamethasone suppression test (DST) that causes the production of cortisol to decrease in healthy horses, but not those with PPID. (sciencedaily.com)
The best tests for hyperadrenocorticism are the low dexamethasone suppression test or the ACTH stimulation test but the results of these sometimes need to be interpreted with caution in diabetic dogs. (safarivet.com)