The purpose of this study was to determine, whether there are any differences in the occurrence of nervous system involvement in different systemic rheumatic diseases. The further aim of the present study was to identify and distinguish primary involvement of the nervous system by these diseases and involvement that may be secondary to confounding factors.
The patient population consisted of 122 patients with a connective tissue disease (42 with systemic lupus erythematosus (SLE), 48 with Sjögren's syndrome and 32 with scleroderma). The methods included neurological examination and standard electrophysiological tests.
At least one neurological defect was diagnosed in 69% of SLE patients, in 71% of Sjögren's syndrome patients and in 66% of scleroderma patients. Secondary factors might have contributed to the pathogenesis of neurological symptoms and signs in up to 25-34% of events.
No significant differences were noted in the occurrence of neurological events in patients with SLE, Sjögren's syndrome and scleroderma. The necessity to differentiate between neurological phenomena directly attributed to the systemic rheumatic disease and those which are totally unrelated or secondary events resulting indirectly from involvement of other organ systems is emphasized.