Glutamic Acid Decarboxylase 65 Antibody-associated Epilepsy and Diplopia: Two Case Reports with Literature Review

Glutamic acid decarboxylase 65 (GAD65) antibody-associated epilepsy and diplopia are relatively rare. This article retrospectively analyzed the disease development, diagnosis and treatment process of two cases of GAD65-associated epilepsy with diplopia. Both patients initially exhibited seizures, followed by the onset of diplopia and nystagmus. Due to differences in their diagnostic processes, the two patients showed varying prognoses after treatment. When diplopia and nystagmus are present in patients with epilepsy, these symptoms are often easily attributed to the side effects of antiepileptic medications or not associated with the epilepsy, potentially leading to the oversight of the possibility of GAD65 neurological syndrome. Therefore, clinicians should be aware of the potential association of anti-GAD65 antibodies in epilepsy patients presenting with diplopia, avoidance of missed diagnosis. Furthermore, diplopia and nystagmus may be precursors to ataxia, therefore, when diplopia occurs, proactive treatment should be initiated to prevent disease progression and avoid poor patient outcomes.