Serum Glial Fibrillary Acidic Protein as a Diagnostic Biomarker in Dogs with Progressive Myelomalacia

Abstract

In humans, increased levels of GFAP in the CSF and blood have been reported with various neural diseases. However, there has been no study describing the usefulness of GFAP in the blood for disease of the spinal cord in dogs. The aim of this study was to describe the utility of GFAP in serum for a diagnosis of progressive myelomalacia. Fifty-six dogs with acute thoracolumbar IVDD diagnosed by computed tomography with myelography or MRI were included. Serum specimens were collected at initial presentation from all cases and at follow-up examinations from some cases. Serum samples were assayed for GFAP concentrations using a commercially available GFAP ELISA Kit. Progressive myelomalacia was the final diagnosis in 8/51 cases (15.6%). Eight dogs had clinical signs suggestive of progressive myelomalacia, of which 6 were positive and 2 were negative by GFAP. Seven dogs had a detectable level of serum GFAP, of which 6 had the onset of progressive myelomalacia. The sensitivity and specificity of the GFAP to progressive myelomalacia were 75% and 97.7%, respectively. The results suggest the utility of GFAP in serum in the diagnosis of progressive myelomalacia.