1 Department of Neurology (JCW, TAM, SP), Divisions of Rheumatology, Immunology and Allergy (JAS) and Pulmonary and Critical Care (TJD), Department of Medicine, and Department of Pathology (VAP), Brigham and Women's Hospital; Harvard Medical School (JCW, JAS, TJD, VAP, TAM, SP), Boston; and Department of Neurology (JCW), Massachusetts General Hospital, Boston.