In a recent clinical study using systematic prolonged Video-EEG in patients with LGI1 and CASPR2 antibody encephalitis, seizures were recorded in 4 out of 20 patients that had been subjectively “seizure-free” for at least 3 months (Baumgartner et al., 2022) suggesting a proportion of patients may have persistent seizures that have not been identified. The gene discussed is CNTNAP2; the disease is viral encephalitis.