title: Two-year outcome of thymectomy with or without immunosuppressive treatment in nonthymomatous myasthenia gravis and its effect on regulatory T cells.
abstract: BACKGROUND
  Myasthenia gravis (MG) is the autoimmune disorder in which the thymus is considered the pathogenic organ. Thymectomy (TE) is a therapeutic option for MG and often ameliorates clinical symptoms.
  
  
  METHODS
  We evaluated clinical features and outcomes after TE in patients without thymoma and the influence of TE with or without concomitant immunotherapy on the CD4(+)CD25(+) regulatory T cell subpopulation of lymphocytes in peripheral blood in defined followed groups of nonthymomatous MG patients.
  
  
  RESULTS
  A total of 46 patients with generalized MG who underwent transsternal TE were identified. Neurologic outcomes after TE were favorable for the majority of patients mainly from the group treated with corticosteroids or combined immunosuppressive treatment. TEs with immunosuppressive treatment in MG patients were associated with increased percentages of CD4(+)CD25(+) cells (p<0.001). No significant change in the postoperative levels of CD4(+)CD25(+) cells was observed in thymectomized patients who preoperatively only received pyridostigmine. Also their clinical response to TE after 2 years of follow-up was worst of all followed groups.
  
  
  CONCLUSIONS
  The exact mechanism by which TE ameliorates symptoms of MG is yet not clear. These observations indicate that increased percentages of CD4(+)CD25(+) T cells in MG may be related to disease stability and that TE and synergistic effect with concomitant, continuing immunotherapy augmented the proportion of CD4(+)CD25(+) T cells. On the basis of our observations TE alone is not enough to increase the number of circulating CD4(+)CD25(+) regulatory T cells and to establish complete stable remission.
authors: Department of Neurology and Clinical Neuroscience Center, 1st Faculty of Medicine of Charles University and General Teaching Hospital in Prague, Czech Republic. Electronic address: michala.jakubikova@vfn.cz.
authors: Michala
authors: M
authors: Jakubíková
authors: Department of Neurology and Clinical Neuroscience Center, 1st Faculty of Medicine of Charles University and General Teaching Hospital in Prague, Czech Republic.
authors: Jiří
authors: J
authors: Piťha
authors: Department of Immunology and Microbiology, 1st Faculty of Medicine of Charles University and General Teaching Hospital in Prague, Czech Republic.
authors: Helena
authors: H
authors: Marečková
authors: Department of Neurology and Clinical Neuroscience Center, 1st Faculty of Medicine of Charles University and General Teaching Hospital in Prague, Czech Republic.
authors: Michaela
authors: M
authors: Týblová
authors: Department of Neurology and Clinical Neuroscience Center, 1st Faculty of Medicine of Charles University and General Teaching Hospital in Prague, Czech Republic.
authors: Iveta
authors: I
authors: Nováková
authors: Third Department of Surgery, 1st Faculty of Medicine of Charles University and University Hospital Motol, Czech Republic.
authors: Jan
authors: J
authors: Schutzner
mesh_terms: D000305:Adrenal Cortex Hormones / Q000627:therapeutic use*; D000328:Adult; D015704:CD4 Antigens; D018791:CD4 Lymphocyte Count; D003131:Combined Modality Therapy; D004359:Drug Therapy, Combination; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D053645:Interleukin-2 Receptor alpha Subunit; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D009157:Myasthenia Gravis / Q000097:blood* / Q000188:drug therapy / Q000601:surgery*; D017063:Outcome Assessment, Health Care; D050378:T-Lymphocytes, Regulatory; D013934:Thymectomy / Q000379:methods*; D055815:Young Adult
chemical_list: D000305:Adrenal Cortex Hormones; D015704:CD4 Antigens; C508017:IL2RA protein, human; D007166:Immunosuppressive Agents; D053645:Interleukin-2 Receptor alpha Subunit
keywords: CD4(+) CD25(+) regulatory T-lymphocytes; Combined immunosuppressive treatment; Corticosteroids; Myasthenia gravis; Pyridostigmine; QMG score; Thymectomy