CASE PRESENTATION: A 40 year old female with a history of autism and iron deficiency anemia presented for an elective endoscopy. During the procedure, she developed respiratory distress and was intubated. She was successfully extubated after the procedure but became apneic and desaturated, requiring re-intubation. Initial blood gases showed hypoxia and hypercarbia. Chest x-ray, CT-thorax and basic laboratory studies were negative for any causes that could explain her respiratory failure. She was eventually extubated but continued to require BiPAP support. Her neurological exam was notable for neck flexion weakness, difficulty sustaining effort and nasal voice. Reflexes were normal. LP and CT-head were negative. A barium swallow study showed oropharyngeal dysphagia with aspiration of thin liquids. Workup was then initiated to rule out neuromuscular disease and anti-MuSK antibody levels was found to be elevated at 83.4 nmol/L, which indicated anti-MuSK antibody positive MG. She received 5 sessions of IVIG with complete resolution of her respiratory failure, dysphagia and weakness. She completed a prednisone taper and is currently asymptomatic on pyridostigmine.