More interestingly, they found that disease activity, as measured by the ESSDAI, was significantly higher in these patients and there was a significant association between SGUS scores and lymphoma risk factors, including germinal center-like structures in the minor salivary gland, CD4+ T cell lymphopenia, reduced number of memory B cells in the circulation, monoclonal immunoglobulin in serum, presence of salivary gland swelling, purpura, and skin vasculitis. This evidence concerns the gene CD4 and purpura.