title: Clinical findings in MuSK-antibody positive myasthenia gravis: a U.S. experience.
abstract: We performed a retrospective chart review on 53 muscle-specific kinase antibody (MuSK-Ab)-positive myasthenia gravis (MG) patients at nine university-based centers in the U.S. Of these, 66% were Caucasian, 85% were women, and age of onset was 9-79 years. Twenty-seven patients were nonresponsive to anticholinesterase therapy. Myasthenia Gravis Foundation of America improvement status was achieved in 53% patients on corticosteroids, 51% with plasma exchange, and in 20% on intravenous immunoglobulin (IVIG). Thymectomy was beneficial in 7/18 patients at 3 years. Long-term (> or =3 years) outcome was very favorable in 58% of patients who achieved remission and/or minimal manifestation status. Overall, 73% improved. There was one MG-related death. This survey reinforces several cardinal features of MuSK-Ab-positive MG, including prominent bulbar involvement and anticholinesterase nonresponsiveness. Facial or tongue atrophy was rare. Most patients respond favorably to immunotherapy. The best clinical response was to corticosteroids and plasma exchange, and the poorest response was to IVIG. Long-term outcome is favorable in about 60% of cases.
authors.affiliation: University of Kansas Medical Center, 3901 Rainbow Boulevard, Mail Stop 2012, Kansas City, Kansas 66160, USA. mpasnoor@kumc.edu
authors.forename: Mamatha
authors.initials: M
authors.lastname: Pasnoor
authors.forename: Gil I
authors.initials: GI
authors.lastname: Wolfe
authors.forename: Sharon
authors.initials: S
authors.lastname: Nations
authors.forename: Jaya
authors.initials: J
authors.lastname: Trivedi
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Barohn
authors.forename: Laura
authors.initials: L
authors.lastname: Herbelin
authors.forename: April
authors.initials: A
authors.lastname: McVey
authors.forename: Mazen
authors.initials: M
authors.lastname: Dimachkie
authors.forename: John
authors.initials: J
authors.lastname: Kissel
authors.forename: Ronan
authors.initials: R
authors.lastname: Walsh
authors.forename: Anthony
authors.initials: A
authors.lastname: Amato
authors.forename: Tahseen
authors.initials: T
authors.lastname: Mozaffar
authors.forename: Marcel
authors.initials: M
authors.lastname: Hungs
authors.forename: Luis
authors.initials: L
authors.lastname: Chui
authors.forename: Jonathan
authors.initials: J
authors.lastname: Goldstein
authors.forename: Steven
authors.initials: S
authors.lastname: Novella
authors.forename: Ted
authors.initials: T
authors.lastname: Burns
authors.forename: Lawrence
authors.initials: L
authors.lastname: Phillips
authors.forename: Gwendolyn
authors.initials: G
authors.lastname: Claussen
authors.forename: Angela
authors.initials: A
authors.lastname: Young
authors.forename: Tulio
authors.initials: T
authors.lastname: Bertorini
authors.forename: Shin
authors.initials: S
authors.lastname: Oh
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D002648:Child; D018572:Disease-Free Survival; D004576:Electromyography; D005260:Female; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000627:therapeutic use; D007167:Immunotherapy; D008297:Male; D008499:Medical Records; D008875:Middle Aged; D009157:Myasthenia Gravis / Q000276:immunology* / Q000628:therapy*; D010951:Plasma Exchange; D011241:Prednisone / Q000627:therapeutic use; D020794:Receptor Protein-Tyrosine Kinases / Q000276:immunology*; D011950:Receptors, Cholinergic / Q000276:immunology*; D012074:Remission Induction; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013934:Thymectomy; D016896:Treatment Outcome; D014481:United States
chemical_list: D016756:Immunoglobulins, Intravenous; D011950:Receptors, Cholinergic; C095714:MUSK protein, human; D020794:Receptor Protein-Tyrosine Kinases; D011241:Prednisone