CD44 and chronic kidney disease: ROC analysis showed that serum CD44 level distinguished active LN from healthy subjects with sensitivity and specificity rates of 97.56% and 100.00% respectively (P<0.001), from LN patients in remission with sensitivity and specificity rates of 89.74% and 90.24% respectively (P<0.001), from active non-renal SLE with sensitivity and specificity rates of 100.00% and 95.12% respectively (P<0.001), and from CKD patients with sensitivity and specificity rates of 100.00% and 97.56% respectively (P<0.001) (Figure 5L, Table 3).