A 20-year old woman has fluctuating weakness

A 20-year old woman with past medical history of hypertension presented with a two-year history of fluctuating muscle weakness.  She has increasing difficulty raising her arms to comb her hair and standing up from a chair.  Six months ago she started to have intermittent double vision and difficulty chewing at night.  She has no numbness or pain.  On neurological exam, mild left ptosis and mild bilateral facial weakness.  Limb muscle strength is 4/5 in the proximal and 5/5 in the distal muscles.  No muscle atrophy.  Deep tendon reflexes, sensation, and coordination are normal.  She has difficulty with tandem.

Question 1:  Where do you localize the patient's lesion?

  1. Motor cortex of the frontal lobe.
  2. Cerebral peduncle of the midbrain.
  3. Anterior horn of the spinal cord.
  4. Neuromuscular junction.
  5. Skeletal muscle.


Question 2.  What test you can do at bedside for more information to support your clinical diagnosis?


  1. Fundoscope for papilledema.
  2. Tensilon test.
  3. Straight leg raise test.
  4. Lumbar puncture with open pressure measure and CSF studies.
  5. Hall-Pike maneuver.


Question 3.  What specific study may you want to order for more certain diagnosis?


  1. Head CAT scan.
  2. MRI of spine with and without gadolinium.
  3. Muscle biopsy.
  4. Nerve conduction study with repetitive nerve stimulation.
  5. Vision evoked potentials.


Question 4.  If patient develops dysphagia and difficulty breathing, what will you do next?

  1. Thiamine 100mg p.o. daily.
  2. Vitamin B12 1000mcg subcutaneous injection daily for 5-7 days.
  3. Avonex 30mcg subcutaneous injection weekly.
  4. Admission, vital capacity monitoring, and Solumedrol 1000mg intravenous bolus daily for five days.
  5. Admission, vital capacity monitoring, and intravenous immunoglobulin or plasmapheresis.