However, available neuropathology reports have demonstrated neuroinflammatory changes, which may be a result of the IgG1 antibodies, the second most commonly detected subclass.37 In one study, patients with CASPR2 antibodies and subsequent hippocampal atrophy were all shown to harbour IgG1 antibodies,21 and our recent observations suggest that higher levels of serum IgG1 LGI1 antibodies correlate with increasing cognitive impairment (Makuch and Irani, unpublished). This evidence concerns the gene LGI1 and hippocampal atrophy.