Glial Fibrillary Acidic Protein Astrocytopathy Based on a Two-Center Chinese Cohort Study.

Objective: Glial fibrillary acidic protein astrocytopathy (GFAP-A) is a recently defined nosological form belonging to the class of autoimmune inflammatory disorders affecting the central nervous system (CNS). Here, we report the clinical and MRI characteristics, treatment, and prognosis of a GFAP-A cohort from two centers in China.

Methods: We retrospectively analyzed the data from 38 adult patients with positive GFAP antibodies and diagnosed as GFAP-A between June 2019 and September 2024. Clinical features, semiquantitative antibody test results, MRI features, treatment approaches, and prognosis were collected.

Results: Among the 38 patients, 24 were male, and the median age at disease onset was 49.5 years. The clinical phenotype included encephalomyelitis (28.9%), myelitis (23.7%), encephalitis (18.4%), meningoencephalomyelitis (18.4%), meningitis/spinal meningitis (7.9%), and peripheral neuropathy (2.6%). In enhanced MRI images, 4 (10.5%) of the patients showed enhancement of the cerebral meninges, 2 (5.3%) had enhancement of the ependyma, and 5 (13.2%) had enhancement of the spinal cord pia mater. 77.1% of the patients responded to the glucocorticoid treatment, while 65.8% had a monophasic course. Spearman correlation analysis showed that CSF-specific oligoclonal bands were significantly correlated with 1-year relapse (CI = 0.527, p = 0.003).

Interpretation: The clinical manifestations of GFAP-A are highly diverse, encompassing encephalitis, myelitis, and meningitis, including spinal meningitis. The enhancement of the spinal pia mater and ependyma on MRI was confirmed. Most patients exhibit a positive response to glucocorticoid therapy. The presence of CSF-specific oligoclonal bands could potentially serve as an indicator for predicting recurrence.