30. Facial neuropathy as the initial manifestation of chronic inflammatory demyelinating polyradiculopathy

We report the clinical and electrophysiological features of a patient who presented unilateral facial weakness as the initial manifestation of chronic inflammatory demyelinating polyradiculopathy (CIDP). A 40-year-old man presented facial numbness and weakness. Examination demonstrated severe unilateral facial weakness with no other cranial or segmental clinical abnormalities. Blink and jaw-jerk reflex latencies were prolonged bilaterally, with a reduction of R1 amplitude recording by the symptomatic side. Somatic neurophysiological examination showed slowing of motor nerve conduction velocities, lengthening of distal motor latencies, prolonged minimal F wave latencies and partial conduction motor block, without any unusual sensory electroneurophysiological abnormalities. Cerebrospinal fluid demonstrated an elevated protein level. After 1 week of intravenous immunoglobulin treatment, the symptoms and electrophysiological findings improved. This case could represent an unusual initial presentation of isolated cranial nerve involvement in asymptomatic CIDP. Blink reflexes may be a useful electrophysiological technique to assess for peripheral nerve demyelination in patients with suspected CIDP.