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Introduction Antibodies to the voltage-gated potassium channel (VGKC) complex and glutamic acid decarboxylase (GAD) have been reported in some cases of psychosis. We conducted the first systematic review on VGKC and GAD, and meta-analysis on GAD, to investigate their prevalence in people with psychosis. Objectives The objective was to examine the available evidence to determine the prevalence of serum VGKC and GAD antibody positivity in psychosis. Aims To search the available literature for data indicating the prevalence of these antibodies in psychosis. If data were sufficient, we anticipated conducting a meta-analysis. Methods Two authors searched major electronic databases for studies reporting the prevalence of VGKC and GAD65 antibody seropositivity in psychotic disorders. We then conducted a random effects analysis with Comprehensive Meta-Analysis software (CMA, Version 3). Results Only three studies presenting prevalence rates of VGKC sero-positivity in psychosis could be identified, with an overall prevalence of 0.5% (1/196) with to 0% in healthy controls (0/50). Meta-analysis established the pooled prevalence of GAD65 autoantibodies was 8.67% (95% CI 3.9–17.80%, I 2 = 75%, 8 studies) in psychotic disorders. People with psychosis were more likely to have GAD65 antibodies than controls (OR 3.14 95% CI 1.55–6.37%, P = 0.001, 7 studies, I 2 = 0%). Conclusions Rates of VGKC antibody positivity appear to be low in psychosis, although there is a lack of published evidence. The prevalence of GAD65 antibodies is higher but available studies did not control for the presence of T1 diabetes, a condition in which GAD65 antibodies are also found. [ABSTRACT FROM AUTHOR]

Antibodies to the voltage-gated potassium channel (VGKC) complex and glutamic acid decarboxylase (GAD) have been reported in some cases of psychosis. We conducted the first systematic review and meta-analysis to investigate their prevalence in people with psychosis and report a case series of VGKC-complex antibodies in refractory psychosis. Only five studies presenting prevalence rates of VGKC seropositivity in psychosis were identified, in addition to our case series, with an overall prevalence of 1.5% (25/1720) compared to 0.7% in healthy controls (12/1753). Meta-analysis established that the pooled prevalence of GAD65 autoantibodies was 5.8% (95% confidence interval [CI]: 2.0-15.6%; I 2  = 91%; nine studies) in psychotic disorders, with a prevalence of 4.6% (95%CI: 1.2-15.9%; nine studies; I 2  = 89%) and 6.2% (95%CI: 1.2-27.0%; two studies; I 2  = 69%) in schizophrenia and bipolar disorder, respectively. People with psychosis were more likely to have GAD65 antibodies than controls (odds ratio [OR], 2.24; 95%CI: 1.28-3.92%; P = 0.005; eight studies; I 2  = 0%). Among 21 participants with treatment-resistant psychosis, none had VGKC antibodies. The prevalence of VGKC antibodies is low in psychosis. Our preliminary meta-analysis suggests that GAD autoantibodies are more common in people with psychosis than in controls, although few studies accounted for the possibility of co-existing type 1 diabetes mellitus and the clinical significance of reported GAD titers remains unclear. The paucity of studies reporting thresholds for defining GAD abnormality and rates of comorbid type 1 diabetes mellitus precludes interpretations regarding the influence of GAD antibodies on the development of psychotic disorders and may have led to an overestimate of the prevalence of GAD. Our case series fails to support the hypothesis that VGKC antibodies are linked to treatment resistance in psychosis, but the literature to date is remarkably sparse., (© 2017 The Authors. Psychiatry and Clinical Neurosciences © 2017 Japanese Society of Psychiatry and Neurology.)

Prevention of graft-versus-host disease (GVHD) is paramount for allogeneic hematopoietic stem cell transplantation (HSCT) to treat nonmalignant diseases. We previously reported that allogeneic HSCT for severe aplastic anemia (SAA) using the fludarabine, cyclophosphamide, and alemtuzumab (Campath-1H) (FCC) regimen is associated with a very low risk of GVHD and excellent clinical outcomes. We now report a single-center study of 45 patients with longer follow-up and investigation of lymphocyte recovery. Overall survival (OS) was 93%, and event-free survival (EFS) was 90.7%. Acute and chronic GVHD each occurred in 6 patients (13.3%), and only 1 case was severe. Mixed T cell chimerism was frequent and persisted after cessation of immunosuppression. T cells were extensively depleted, representing only 11.3% of lymphocytes at day 30 and rising to 43.8% by 1 year, but still significantly below normal levels (67.2%; P = .018), and deficiency persisted after immunosuppressive therapy (IST) withdrawal. Depletion of CD4 T cells was particularly profound, causing inversion of the normal CD4:CD8 T cell ratio. T cell subset composition was also abnormal, with memory and effector T cells predominating for at least 6 months after FCC HSCT. Analysis of T cell subset chimerism showed that CD4 T cells were predominantly donor-derived at 1 year, whereas recipient-derived CD8 T cells shaped mixed chimerism with a notable contribution of recipient effector CD8 T cells. The prolonged mixed T cell chimerism after IST withdrawal and low incidence of GVHD indicates the establishment of mutual tolerance, but the low incidence of viral disease suggests maintenance of antiviral immunity. Our study shows that despite the abnormal T cell profile after allogeneic HSCT for SAA using the FCC regimen, this regimen is conducive to an excellent clinical outcome., (Copyright © 2017 The American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.)