A 47-year-old gentleman presented a with 2-year history of bilateral ptosis, diplopia, and bulbar weakness. Neostigmine test and RNS were positive, while CECT of the chest was normal. Anti-AChR antibody was negative. Symptoms responded to steroids, pyridostigmine, and azathioprine. He was well for the next 2 years when he had developed severe bulbar weakness and respiratory difficulty. Anti-MuSK was positive, and five cycles of plasma exchange were administered with no response. IV rituximab was then started with good response after two doses, steroids and immunomodulation were tapered, and rituximab was given weekly for 4 weeks every 6 months. He is symptom free on 2-year follow-up.
A 49-year-old lady with MuSK-positive MG, diagnosed outside and treated with steroids, presented with fever, cough, and breathlessness for 2 weeks. Keeping a possibility of community-acquired pneumonia, she was managed with IV antibiotics with which her fever improved, but her dyspnea continued. Myasthenia crisis was considered, and a cycle of IVIG (2 g/kg) followed by IV cyclophosphamide was given with mild improvement. She was continuing monthly IV cyclophosphamide but never attained remission. She was then started on IV rituximab (375 mg/m2 weekly for 4 weeks), to which she responded remarkably with complete resolution of respiratory difficulty and other symptoms.