Drug-resistant seizures are common in patients with leucine-rich, glioma-inactivated 1 (LGI1)-IgG associated and contactin-associated protein-like 2 (CASPR2)-IgG associated encephalitis.
Its safety, immunological effects and therapeutic potential was evaluated in a 60-year old patient with life-threatening and treatment-refractory anti-CASPR2encephalitis requiring medical care and artificial ventilation in an intensive care unit.
With the limitations imposed by the low number of cases, differences to published adult cohorts included: absence of faciobrachial dystonic seizures and hyponatremia in patients with LGI1-positive encephalitis; slightly higher proportion of isolated epilepsy syndromes in CASPR2-positive patients; absence of tumour in the whole cohort.
These results suggest that mutations in CNTNAP2 may contribute to alterations in AMPA receptor function and homoeostatic plasticity, and indicate that antibodies from anti-CASPR2encephalitis patients affect cortical excitatory transmission.
Fifteen patients (an average age of 6.8, 14 patients with anti-NMDAR encephalitis and 1 patient with anti-CASPR2encephalitis) presented seizure remission without any AEDs.
The clinical phenotypes of anti-LGI1 encephalitis and anti-Caspr2encephalitis have been described in more detail including data on treatment and long-term follow-up.