A 34-year-old man initially presented to neurology clinic for 6 months of progressively worsening gait difficulty along with numbness and spasms in his hands and feet.  He had past medical history of T cell lymphoma and congenital cardiac disease including an aortic valve replacement and pacemaker on anticoagulation. 

Neurologic exam was notable for decreased sensation to vibration and light touch in hands and feet along with grip myotonia. EMG/NCS showed no large fiber polyneuropathy but signs of pseudomyotonia. Genetic testing subsequently confirmed a diagnosis of MC however this did not fully explain his sensory and gait symptoms.  Due to his pacemaker he was unable to undergo MRI. CT of brain and spine were unremarkable. Ocular Coherence Tomography (OCT) revealed right optic nerve atrophy. CSF sampling was obtained and positive for Oligoclonal Bands.  A diagnosis of PPMS was made and he was started on disease modifying therapy.   Of note, the patient’s father was also diagnosed with both MC and MS.

This case describes a patient with multiple neurologic symptoms who was ultimately diagnosed with both MC and PPMS, highlighting the importance of a thorough neurologic work-up to ensure the diagnosis accounts for all the presenting neurologic symptoms. It also raises the question of whether there could be a common underlying mechanism in these disorders.