title: Double seronegative myasthenia gravis with anti-LRP 4 antibodies.
abstract: About 10% of patients with generalized myasthenia gravis do not have detectable antibodies to acetylcholine receptor or muscle specific kinase (double seronegative myasthenia). The presence of anti-low density lipoprotein receptor-related protein 4 antibodies (LRP4 Abs) has recently been reported in variable proportion of double seronegative cases. We report the presenting characteristics of two double seronegative myasthenic patients from Greece with anti-LRP4 antibodies shortly after disease onset. The first patient, a 52-year-old male, presented with a one month history of isolated neck extensor weakness; the second patient is a 52-year-old female with three months history of ocular-bulbar-cervical myasthenic weakness. Both patients presented with mild severity and responded promptly and adequately to pyridostigmine. In the female patient thymic residual tissue was detected on CT of the mediastinum. She underwent thymectomy, and histological examination revealed follicular hyperplasia. This is the first clinical report of the presenting features of newly diagnosed myasthenia with anti-LRP4 antibodies. The clinical and therapeutic implications of the anti-LRP4 antibody positivity remain to be clarified.
authors.affiliation: Neurology Department, Aeginition Hospital, University of Athens, Greece. vzouvelu@med.uoa.gr
authors.forename: Vasiliki
authors.initials: V
authors.lastname: Zouvelou
authors.forename: Paraskevi
authors.initials: P
authors.lastname: Zisimopoulou
authors.forename: Michael
authors.initials: M
authors.lastname: Rentzos
authors.forename: Nikos
authors.initials: N
authors.lastname: Karandreas
authors.forename: Panagiota
authors.initials: P
authors.lastname: Evangelakou
authors.forename: Eleftherios
authors.initials: E
authors.lastname: Stamboulis
authors.forename: Socrates J
authors.initials: SJ
authors.lastname: Tzartos
mesh_terms: D001323:Autoantibodies / Q000097:blood*; D005260:Female; D006801:Humans; D026502:LDL-Receptor Related Proteins / Q000097:blood / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D009157:Myasthenia Gravis / Q000175:diagnosis / Q000188:drug therapy* / Q000276:immunology; D011729:Pyridostigmine Bromide / Q000627:therapeutic use; D020794:Receptor Protein-Tyrosine Kinases / Q000276:immunology; D013934:Thymectomy / Q000379:methods; D016896:Treatment Outcome
chemical_list: D001323:Autoantibodies; D026502:LDL-Receptor Related Proteins; C551781:LRP4 protein, human; D020794:Receptor Protein-Tyrosine Kinases; D011729:Pyridostigmine Bromide