Assignment task:
A 35-year-old female presented to her primary care provider complaining of fatigue and weakness to her extremities that worsens throughout the day. She states that her weakness does improve at rest, however, she feels most strong in the morning upon awakening. The patient also mentions intermittent inconsistent episodes of slurred speech, difficulty swallowing, and mentions episodes where her head would involuntarily "drop" over the past several weeks. Her primary care provider tested routine blood work, all of which were unremarkable. Her symptoms were attributed to a vitamin B12 deficiency and she was advised to start taking vitamin B12 supplements to help improve her symptoms. Two weeks later, the patient presents to the emergency room in severe respiratory distress for which the patient was placed on BiPAP under observational status with consideration for intubation. Once stabilized and started on corticosteroids, a physical examination is performed. The patient is noted to have right-sided ptosis. On neurologic examination, the patient is noted to have 3/5 strength to her upper and lower extremities bilaterally. When asked to sit up, the patient is able to sit up with assistance, however, she is unable to maintain an upright posture without assistance, suggestive of a mild truncal ataxia. Based on the patient's clinical description, what is most likely the diagnosis missed by her primary care provider and what is the appropriate treatment moving forward for this patient? Please be sure to address the etiology of the patient's condition in your initial response.