• Jennifer L Kruse, Maria I Lapid, Vanda A Lennon, Christopher J Klein, Orna O' Toole, Sean J Pittock, Edythe A Strand, Mark A Frye, and Andrew McKeon.
• Department of Psychiatry and Psychology, College of Medicine, Mayo Clinic, Rochester, MN.
• Psychosomatics. 2015 May 1; 56 (3): 227-41.

BackgroundDescriptions of psychiatric autoimmunity beyond N-methyl-D-aspartate (NMDA) receptor encephalitis are sparse.ObjectiveTo report the autoimmune psychiatric spectrum currently recognized in Mayo Clinic practice.MethodsMedical record review, testing of stored serum and cerebrospinal fluid for IgGs reactive with synaptic receptors and ion channels, neuronal nuclear and cytoplasmic antigens (including glutamic acid decarboxylase 65-kDa isoform) and case-control comparison were conducted. Patients were categorized into group 1, all adult psychiatric inpatients tested for neural autoantibodies (2002-2011; n = 213), and group 2, all Mayo NMDA receptor IgG-positive patients (2009-2013; n = 13); healthy control subjects were also included (n = 173).ResultsIn group 1, at least 1 serum autoantibody (but not NMDA receptor IgG) was detected in 36 of 213 psychiatric inpatients. In total, 12 patients were determined retrospectively to have high-likelihood autoimmune encephalitic diagnoses. The most commonly detected autoantibody specificities were voltage-gated potassium channel ([Kv1] VGKC) complex (6) and calcium channel (P/Q type or N type; 5). Symptoms seen were as follows: depressive (8), anxious (7), psychotic (7), disorganized (5), suicidal (3), manic (1) and catatonic (1). In group 2, among 13 NMDA receptor IgG-positive patients, 12 had encephalitis; their psychiatric symptoms were as follows: depressive (9), catatonic (9), disorganized (8), anxious (8), psychotic (7), manic (6), and suicidal (3). Catatonic symptoms were more common in the 12 NMDA receptor IgG-positive patients than in the 12 group 1 patients with high likelihood of encephalitis (p = 0.002). Antibody positivities were usually low positive in value among healthy controls (12 of 16 vs 3 of 12 group 1 encephalitis cases, p = 0.025). NMDA receptor IgG was not detected in any healthy control subject.ConclusionsA spectrum of psychiatric autoimmunity beyond NMDA-R IgG may be under-recognized. Diagnosis is facilitated by combining results of comprehensive psychiatric, laboratory, radiologic, and electrophysiologic evaluations.Copyright © 2015 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.

63 keywords...

hide…