title: Low-Density Lipoprotein Receptor-Related Protein 4-Positive Myasthenia Gravis in a Double-Seronegative, Electromyography-Negative Patient.
abstract: We describe a patient with ocular myasthenia gravis, where single-fiber electromyography and testing for acetylcholine receptor and muscle-specific kinase antibodies were negative. However, antibodies to low-density lipoprotein receptor-related protein 4 (LRP4) were positive, and this prompted appropriate management. We recommend that testing for LRP4 antibodies be considered when the clinical suspicion for myasthenia gravis is high despite negative conventional diagnostic tests.
authors.affiliation: Department of Ophthalmology (JMK), Hadassah Medical Center, Kiryat Hadassah, Jerusalem, Israel; Neuroimmunology and Cell Therapy Unit (DK, PP), Neurology Department, Hadassah-Hebrew University Medical Center, Jerusalem, Israel; and Department of Neurobiology (PZ), Hellenic Pasteur Institute, Greece and Tzartos NeuroDiagnostics, Athens, Greece.
authors.forename: Joshua M
authors.initials: JM
authors.lastname: Kruger
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Karussis
authors.forename: Paraskevi
authors.initials: P
authors.lastname: Zisimopoulou
authors.forename: Panayiota
authors.initials: P
authors.lastname: Petrou
mesh_terms: D001323:Autoantibodies / Q000097:blood* / Q000276:immunology; D001763:Blepharoptosis / Q000175:diagnosis / Q000209:etiology*; D003937:Diagnosis, Differential; D004172:Diplopia / Q000175:diagnosis / Q000209:etiology*; D004576:Electromyography / Q000379:methods*; D006801:Humans; D026502:LDL-Receptor Related Proteins / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D009157:Myasthenia Gravis / Q000097:blood / Q000150:complications / Q000175:diagnosis*
chemical_list: D001323:Autoantibodies; D026502:LDL-Receptor Related Proteins; C551781:LRP4 protein, human