Since the recognition of antibodies against voltage – gated potassium channel (VGKC) and their pathogenic implication in central nervous system disorders (such as limbic encephalitis) in 2001, critical immunological and neurological advances have been achieved during the last 15 years. One of the main discoveries has been that these VGKC antibodies usually target proteins outside of the channel protein, which are part of the VGKC complex (e.g. contactin-associated protein 2). Moreover, each specific antibody is associated with distinct clinical phenotypes, which commonly overlap.
Clinically the primary neurological syndrome associated with VGKC antibodies is limbic encephalitis, classically presenting with severe memory impairment and secondary hippocampal atrophy. However, recently emerging psychiatric syndromes have been linked to this autoimmune condition.
In the current issue of JNNP, Prüss and Lennox have published a review describing novel psychiatric syndromes associated with VGKC complex antibodies. In the review, the authors described the recent highlights about the pattern of cognitive involvement and reversibility of memory dysfunction in limbic encephalitis, response to treatment with immunotherapy, immunology of VGKC complex antibodies and the relevance of the titre levels, and mood and psychotic disorders associated with VGKC complex antibodies.
Although, evidence regarding the pathogenic role of VGKC complex antibodies in psychiatric conditions is missing and many questions remain to be answered in this field, it is important that neurologists and psychiatrists combine their expertise to gain a better comprehension of this neuropsychiatric disorder. It is relevant for neurologists to be aware of psychiatric manifestations associated with autoimmune channelopathies and for psychiatrists to keep in mind that VGKC complex antibodies could be part of the differential diagnosis in patients with atypical psychiatric manifestations and autoimmune features.
Read more at http://jnnp.bmj.com/content/87/11/1242.full