It is speculated that a potential inflammatory process (meningeal inflammation, viral, or yet unknown) could trigger a CXCL13‐mediated B‐cell attraction and contribute to the development of anti‐NMDAR encephalitis (Leypoldt et al., 2015); however, NMDAR antibodies were detected in CSF only 3 days after headache onset in our case. The gene discussed is CXCL13; the disease is viral encephalitis.