Serum CD44 level was also significantly higher in quiescent LN patients compared to quiescent non-renal SLE patients and healthy subjects (1.57 ± 0.22, 0.54 ± 0.07, 0.37 ± 0.05 ng/ml, P<0.001, quiescent LN vs quiescent non-renal SLE patients or healthy subjects). This evidence concerns the gene CD44 and systemic lupus erythematosus.