Clinical spectrum and prognostic features of patients seropositive for anti-GD1a antibody
Background Anti-GD1a antibodies are associated with a range of immune-mediated neuropathies, particularly acute motor axonal neuropathy (AMAN) and other Guillain-Barré syndrome (GBS) variants. However, their full clinical spectrum and prognostic significance remain unclear due to limited systematic studies. Here, we investigated the clinical phenotypes, serological profiles, cerebrospinal fluid (CSF) characteristic, and therapeutic outcomes associated with anti-GD1a antibodies. Methods The clinical, paraclinical and therapeutic data were retrospectively collected and analyzed from 19 Chinese patients who tested positive for anti-GD1a antibodies. Results The mean age at onset in this cohort was 50.6 years. Among the 19 patients, 14 (74%) presented with acute syndromes. The remaining five patients (26%) exhibited features consistent with chronic neuropathies. Common manifestations included absent tendon reflexes (84%), limb weakness (84%), sensory impairment (58%), and cranial nerve involvement (53%). Isolated anti-GD1a antibody positivity was observed in only 5 patients, while others had co-existing antiganglioside antibodies, most commonly anti-GQ1b, and anti-GM1. Electrophysiological studies revealed axonal and demyelinating neuropathic patterns. Patients with cranial nerve involvement and albuminocytologic dissociation were associated with higher modified Erasmus GBS Outcome Score (mEGOS). Immunotherapy was effective in acute cases, with 57% achieving complete recovery at 6-month follow-up. Conclusions Patients seropositive for anti-GD1a antibody exhibits significant clinical and electrophysiological heterogeneity and frequently coexists with other antiganglioside antibodies. Acute presentations generally respond well to immunotherapy, while chronic cases require individualized management.