Encefalitis autoinmune asociada a anticuerpos anti-LGI1: revisión de sus aspectos clínicos, diagnósticos y terapéuticos

Autoimmune encephalitis associated with anti-LGI1 antibodies is one of the most recognized forms of immune-mediated limbic encephalitis. This condition typically presents with a subacute course of focal seizures, behavioral disturbances, and memory impairment, often accompanied by faciobrachial dystonic seizures. Unlike other types of autoimmune encephalitis, its association with neoplasms is uncommon; however, early recognition is essential due to its favorable prognosis when promptly treated. Diagnosis relies on characteristic clinical features, supportive neuroimaging findings, cerebrospinal fluid abnormalities, and detection of anti-LGI1 antibodies in serum or cerebrospinal fluid. First-line treatment includes immunotherapy with corticosteroids, intravenous immunoglobulin, or plasma exchange. In refractory cases, rituximab has demonstrated positive clinical outcomes and lower relapse rates. This article summarizes the epidemiological, pathophysiological, clinical, diagnostic, and therapeutic aspects of this entity, emphasizing the importance of early clinical suspicion. Moreover, it highlights that there are cases with highly suggestive clinical manifestations where antibody titers may be low or undetectable, underscoring the critical role of clinical judgment in the diagnostic process.