Anti-neuron antibody syndrome: clinical features, cytokines/chemokines and predictors

BACKGROUND: Neuroimmunology is a rapidly expanding field, and there have been recent discoveries of new antibodies and neurological syndromes. Most of the current clinical studies have focused on disorders involving one specific antibody. We have summarized a class of antibodies that target common neuronal epitopes, and we have proposed the term “anti-neuron antibody syndrome” (ANAS). In this study, we aimed to clarify the clinical range and analyse the clinical features, cytokines/chemokines and predictors in ANAS. METHODS: This was a retrospective cohort study investigating patients with neurological manifestations that were positive for anti-neuron antibodies. RESULTS: A total of 110 patients were identified, of which 43 patients were classified as having autoimmune encephalitis (AE) and the other 67 were classified as having paraneoplastic neurological syndrome (PNS). With regards to anti-neuron antibodies, 42 patients tested positive for anti-N-methyl-D-aspartate receptor (NMDAR) antibody, 19 for anti-Hu, 14 for anti-Yo and 12 for anti-PNMA2 (Ma2). There were significant differences between the ANAS and control groups in serum B cell-activating factor (BAFF) levels and in cerebrospinal fluid (CSF) C-X-C motif chemokine10 (CXCL10), CXCL13, interleukin10 (IL10), BAFF and transforming growth factor β1 (TGFβ1) levels. Predictors of poor outcomes included having tumours (P = 0.0193) and having a chronic onset (P = 0.0306), and predictors of relapses included having lower levels of CSF BAFF (P = 0.0491) and having a larger ratio of serum TGFβ1/serum CXCL13 (P = 0.0182). CONCLUSIONS: Most patients with ANAS had a relatively good prognosis. Having tumours and a chronic onset were both associated with poor outcomes. CSF BAFF and the ratio of serum TGFβ1/serum CXCL13 were associated with relapses.