Contrasting Outcomes in Two Cases of Anti-contactin-associated Protein-like 2 Autoimmune Encephalitis.

We herein report two cases of anti-contactin-associated protein-like 2 (CASPR2) autoimmune encephalitis in men in their 70s. Both patients presented with seizures and psychiatric symptoms that required sedation and mechanical ventilation. The treatment included high-dose intravenous methylprednisolone, plasma exchange, and rituximab. One patient fully recovered (modified Rankin Scale [mRS] score 0), whereas the other remained severely disabled (mRS score 5). This difference in outcome may be attributed to the time from symptom onset to treatment initiation. These cases highlight the importance of an early diagnosis and timely immunotherapy for anti-CASPR2 autoimmune encephalitis.