High titers of IgG-RF and IgM-RF are likely to lead to rheumatoid vasculitis.[25,26] Higher positive values and titers of RF in RA patients with rheumatoid vasculitis than in RA patients without rheumatoid vasculitis.[27] The occurrence of rheumatoid vasculitis allows for increased exposure of endothelial collagen, which can further activate the endogenous coagulation pathway, leading to local thickening of the vascular intima and stenosis of the lumen. This evidence concerns the gene CD40LG and rheumatoid arthritis.