Glial Fibrillary Acidic Protein Autoimmunity
Alice Gravier-Dumonceau, Roxana Améli, Véronique Rogemond, Anne Ruiz, Bastien Joubert, Sergio Muñiz‐Castrillo, Alberto Vogrig, Géraldine Picard, Aditya Ambati, Marie Bénaiteau, Florence Rulquin, Jonathan Ciron, Kumaran Deiva, T. de Broucker, Laurent Kremer, Philippe Kerschen, François Sellal, B. Bouldoires, Roxana Genet, Julien Biberon, Adrien Bigot, Fanny Duval, Nahéma Issa, Elena-Camelia Rusu, Mathilde Goudot, Anaïs Dutray, J.-L. Devoize, Lucie Hopes, Anne-Laure Kaminsky, Marion Philbert, Eve Chanson, Amélie Leblanc, E. Morvan, Daniela Andriuta, Philippe Diraison, Gabriel Mirebeau, Céline Derollez, Veronique Bourg, Q. Bodard, Clementine Fort, Irina Grigorashvili-Coin, Guillaume Rieul, Daniela Molinier-Tiganas, Mickaël Bonnan, Thierry Tchoumi, Jérôme Honnorat, Romain Marignier
Abstract
BACKGROUND AND OBJECTIVES: To report the clinical, biological, and imaging features and clinical course of a French cohort of patients with glial fibrillary acidic protein (GFAP) autoantibodies. METHODS: We retrospectively included all patients who tested positive for GFAP antibodies in the CSF by immunohistochemistry and confirmed by cell-based assay using cells expressing human GFAPα since 2017 from 2 French referral centers. RESULTS: We identified 46 patients with GFAP antibodies. Median age at onset was 43 years, and 65% were men. Infectious prodromal symptoms were found in 82%. Other autoimmune diseases were found in 22% of patients, and coexisting neural autoantibodies in 11%. Tumors were present in 24%, and T-cell dysfunction in 23%. The most frequent presentation was subacute meningoencephalitis (85%), with cerebellar dysfunction in 57% of cases. Other clinical presentations included myelitis (30%) and visual (35%) and peripheral nervous system involvement (24%). MRI showed perivascular radial enhancement in 32%, periventricular T2 hyperintensity in 41%, brainstem involvement in 31%, leptomeningeal enhancement in 26%, and reversible splenial lesions in 4 cases. A total of 33 of 40 patients had a monophasic course, associated with a good outcome at last follow-up (Rankin Score ≤2: 89%), despite a severe clinical presentation. Adult and pediatric features are similar. Thirty-two patients were treated with immunotherapy. A total of 11/22 patients showed negative conversion of GFAP antibodies. DISCUSSION: GFAP autoimmunity is mainly associated with acute/subacute meningoencephalomyelitis with prodromal symptoms, for which tumors and T-cell dysfunction are frequent triggers. The majority of patients followed a monophasic course with a good outcome.