title: Maintenance plasma exchange treatment for muscle specific kinase antibody positive myasthenia gravis patients.
abstract: BACKGROUND
  Anti-muscle specific kinase antibody positive myasthenia gravis (MuSK MG) is often characterized by a relatively severe and progressive course, refractoriness to standard myasthenia gravis (MG) medications, and an increased risk of myasthenic crisis. We report here successful management of three MuSK MG patients using maintenance therapeutic plasma exchange (TPE) treatment for up to 4.5 years.
  
  
  METHODS
  The study was a 5-year retrospective review of all MG patients treated with TPE between 2008 and 2013 at University of Michigan. Inclusion criteria of MuSK MG were positive for anti-MuSK antibodies and a diagnosis of MuSK MG by staff neurologists. Patient data included age, gender, diagnostic testing results, medications, and the dates and response to TPE treatments.
  
  
  RESULTS
  A total of 153 MG patients underwent at least one course of TPE between 2008 and 2013. A total of 12 patients (7.8%) were positive for anti-MuSK antibodies. Patients were predominantly female (83.3%) and a median age of onset was 46-years old. Three MuSK MG patients were successfully managed with maintenance TPE.
  
  
  CONCLUSIONS
  Maintenance TPE may be an effective option for MuSK MG patients. The key of successful maintenance treatment at our institution has been to tailor the TPE frequency for each individual, and to modify the treatment interval in conjunction with medical management.
authors.affiliation: Division of Transfusion Medicine, Department of Pathology, University of Michigan, Ann Arbor, Michigan.
authors.forename: Chisa
authors.initials: C
authors.lastname: Yamada
authors.affiliation: Division of Neurology, Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan.
authors.forename: James W
authors.initials: JW
authors.lastname: Teener
authors.affiliation: Division of Transfusion Medicine, Department of Pathology, University of Michigan, Ann Arbor, Michigan.
authors.forename: Robertson D
authors.initials: RD
authors.lastname: Davenport
authors.affiliation: Division of Transfusion Medicine, Department of Pathology, University of Michigan, Ann Arbor, Michigan.
authors.forename: Laura
authors.initials: L
authors.lastname: Cooling
mesh_terms: D000328:Adult; D017668:Age of Onset; D001323:Autoantibodies / Q000097:blood / Q000276:immunology*; D001324:Autoantigens / Q000276:immunology*; D055499:Catheter-Related Infections / Q000209:etiology; D003131:Combined Modality Therapy; D004172:Diplopia / Q000209:etiology; D005260:Female; D006801:Humans; D016867:Immunocompromised Host; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007239:Infections / Q000209:etiology; D008297:Male; D008875:Middle Aged; D009157:Myasthenia Gravis / Q000150:complications / Q000188:drug therapy / Q000276:immunology / Q000628:therapy*; D010951:Plasma Exchange; D020794:Receptor Protein-Tyrosine Kinases / Q000276:immunology*; D011950:Receptors, Cholinergic / Q000276:immunology*; D012189:Retrospective Studies; D016896:Treatment Outcome; D062666:Vascular Access Devices
chemical_list: D001323:Autoantibodies; D001324:Autoantigens; D007166:Immunosuppressive Agents; D011950:Receptors, Cholinergic; C095714:MUSK protein, human; D020794:Receptor Protein-Tyrosine Kinases
keywords: MuSK; maintenance plasma exchange; myasthenia gravis