VDI-cCRP measures canine-specific C-reactive protein (cCRP) which is a major acute phase protein produced, mainly in the liver, in response to inflammation and the release of cytokines. Serum CRP has been shown to be an effective measure of general inflammation. The concentration of CRP correlates to both the severity and duration of the inflammatory stimuli.

Acute phase proteins constitute a group of proteins (eg, CRP, haptoglobin, serum amyloid A), part of the innate host defense system, whose blood concentration changes rapidly in response to any tissue damaging causes such as infection, immune-mediated disorders neoplasia, trauma, and others. CRP is produced "de novo" with no storage reserves (ie, low risk of false release). CRP decreases rapidly when inflammatory stimulation is no longer present.

CRP measurements are useful to: a) rule out inflammation, b) guage disease severity, c) monitor efficacy of treatment.