To examine whether levels of soluble adhesion molecules and anti-endothelial cell antibodies (AECA) were elevated in rheumatoid arthritis (RA) complicated by peripheral neuropathy compared to controls with no neurological complications.
Levels of soluble vascular cell adhesion molecule-1 (sVCAM-1), sE-selectin, and AECA were determined by ELISA in 33 patients with RA neuropathy, 23 patients with vasculitis who had no neurological complications, 29 patients with RA without neuropathy, and 25 healthy volunteer controls.
The patients with neuropathy had significantly higher levels of serum sVCAM-1 (mean 1119+/-368 ng/ml) than patients without neuropathy (mean 869+/-214 ng/ml) and healthy controls (mean 578+/-204 ng/ml). Serum levels of sE-selectin were higher among neuropathic patients with RA (mean 73+/-34 ng/ml) than RA controls (mean 45+/-27 ng/ml) and healthy controls(mean 32+/-10 ng/ml). There was no significant difference in serum levels of sVCAM-1, sE-selectin, and AECA between patients with RA with neuropathy and patients with vasculitis uncomplicated by neurological disease. Abnormal levels of sVCAM-1, sE-selectin, or AECA were found in sera from 28 (85%) patients with RA neuropathy, 15 (65%) patients with vasculitis, 9 (31%) RA controls, and 2(8%) healthy controls.
Serum levels of sVCAM-1, sE-selectin, and AECA are higher in patients with RA neuropathy than in patients with RA uncomplicated by neurological disease. These data suggest that development of peripheral neuropathy in RA is associated with increased endothelial cell activation.