A Case of Anti-MuSK Positive Myasthenia Gravis

Anti-MuSK Myasthenia Gravis (MG) is a rare autoimmune neuromuscular junction disorder with poor response to conventional management of MG. We're reporting a case with typical presentation and clinical course of this disorder. 28-year-old lady presented with prominent oculobulbar, proximal muscle and respiratory muscle progressively worsened for the past 8 months with demonstrable fatigability with requiring ventilatory support. She responded poorly to intravenous Immunoglobulin (IVIG), conventional immunosuppressive therapy but improved remarkably with plasmapharesis. Her acetylcholine receptor antibody was negative and anti-MuSK antibodies turn out to be positive (1.15nmol/L). The clinical presentation and the clinical course of this patient corresponds to other reported anti-MuSK positive MG cases. Plasmapharesis appears to be an effective treatment for this group of patients in MG crisis.