Background: Reports about cranial nerve involvement in rheumatoid arthritis are insufficient compared to the frequently reported peripheral nerve involvement. Methods: We investigate the occurrence of electrophysiologically evident peripheral and cranial nerve involvement in 55 patients with rheumatoid arthritis (RA) without manifest neuropathy. Results: Patients mean age was 43.1 years and duration of illness was 6.4 years. All patients presented with electrophysiological findings suggestive of peripheral neuropathy. In addition, 69.1% of them had entrapment neuropathies. Carpal tunnel syndrome (CTS) was the commonest entrapment neuropathy (54.6%). Sensorimotor neuropathy with variable severity at sites other than the usual entrapment sites, was diagnosed in 70.9% while bilateral distal sensory neuropathy in lower limbs was identified in 29.1%. Among cranial nerves examined, optic and vestibulocochlear neuropathies were common (29.1% of eyes and 40% of ears examined respectively). Spinal accessory neuropathy was demonstrated in 21.8% of records. Neither facial nor trigeminal nerves were affected. Electrophysiological characteristics of peripheral and cranial neuropathies were indicative of axon loss. Significant association was identified between presence of neuropathy and patients’ ages, duration of the illness, presence of rheumatoid nodules and advanced disease stages. Conclusions: Prolonged immune-mediated vasculitis is the most likely cause of cranial and peripheral neuropathies. However, neurotoxicity from drugs employed in RA treatment, in addition, can not be excluded.

(Egypt J. Neurol. Psychiat. Neurosurg., 2005, 42(2): 545-558).