Serum Glial Fibrillary Acidic Protein: A Surrogate Marker of the Activity of Multiple Sclerosis

OBJECTIVE: Multiple sclerosis (MS) is a neurodegenerative disorder with various clinical types. Glial fibrillary acidic protein (GFAP) is significantly elevated in the cerebrospinal fluid (CSF) of MS patients compared with that of healthy controls. The aim of this study is to evaluate serum levels of GFAP in relation to disease activity in relapsing-remitting MS patients and to compare them with those of healthy controls. METHOD: This study involved 58 MS patients of relapsing-remitting MS (RRMS) type, 22 in an active stage of the disease and 36 in remission, and 50 healthy individuals as age- and sex-matched controls. Blood samples were taken from the patients at the MS Clinic of the Baghdad Teaching Hospital, and the serum levels of GFAP were determined using the enzyme-linked immunosorbent assay (ELISA) technique. RESULTS: Mean GFAP serum levels in 22 patients presenting in the active state of the disease (6.47±3.39 ng/ml) and 36 cases in remission were (5.33±2.82 ng/ml) (p=0.074) were determined as indicated. When RRMS patients (n=58) were compared with the healthy controls (n=50, 1.89±1.21), the difference in serum levels of GFAP was statistically significant (p<0.001). The area under the curve of the serum measures of GFAP obtained through the receiver operating characteristics was 0.903, which was also statistically significant (p<0.001). CONCLUSION: GFAP biomarker is an indicator of disease activity in RRMS patients, and its serum level may correlate with the state of remission or exacerbation.