Once the diagnosis was established and steroid therapy begun, the patient’s clinical status improved significantly. His dysesthesias diminished, and he regained strength in his lower limbs. Dramatic radiographic resolution of the multifocal opacities occurred over three weeks. He was breathing independently within one week. He was discharged to his home hospital for intensive rehabilitation four weeks after the initiation of steroid therapy.On follow-up, pulmonary function testing revealed a combined mild obstructive and restrictive pattern with a forced expiration volume in 1 s of 2.4 L (69% of predicted), forced vital capacity of 3.6 L (72% of predicted) and a diffusing capacity corrected for lung volume of 3.1 L/min/mmHg (59% of predicted). On neurological examination, he showed better than antigravity strength in all upper limb muscles, with a return of deep tendon reflexes to the biceps and brachioradialis on the right. The lower limbs showed severe muscle atrophy and weakness, with the right greater than the left. Muscle strength testing revealed Medical Research Council grades 2 to 4, with distal muscles weaker than proximal muscles. Vibration sense remained absent at the ankles, and light touch was absent up to the knees bilaterally. Deep tendon reflexes were absent in the lower extremities.