The electroneurophysiological findings in rheumatoid arthritis patients.

In rheumatoid arthritis (RA), vasculitis is a serious complication usually found in patients with long-standing erosive nodular seropositive disease. One clinical hallmark of this systemic arteritis is the appearance of neurological findings. However, it is often difficult to diagnose these slight or early neuropathies and the study of the peripheral neuromuscular system is often made difficult by symptoms resulting from pain in the joints and limitations of movement. It is nevertheless often possible by means of electroneuromyography to show objectively the existence and distribution of even subclinical neuropathies. In order to evaluate the neurophysiological functions of RA patients by means of the peripheral nerve conduction and somatosensorial evoked potential studies, 33 RA patients and 20 healthy controls were included in this study. Two (6%) patients were found to have carpal tunnel syndrome, while 6 (18%) patients had mononeuritis multiplex. Delayed N12, N13, N1 and P1 latencies were detected in 6 (18%) of 33 RA patients suggesting central nervous system involvement with intact peripheral nervous system. Our results confirm earlier observations that symptoms of neuropathy are fairly common in cases of RA without there being any clear correlation with any clinical variable. By means of electroneurophysiological studies, it is to evaluate the integrity of the peripheral nerve, the spine and the central pathways. Besides enabling to detect early subclinical involvement of the peripheral nervous system in RA, SEPs should also be used for the evaluation of subclinical myelopathy due to atlantoaxial subluxation or vasculitis. The inclusion of an electroneurophysiologic examination of the RA patients is recommended in routine diagnostic procedure.