Serum beta-2 microglobulin (B2M) in 100 #SLE pts - strong correlations betw B2M & 24 hr urinary protein, BUN, creatinine, disease activity, & damage score (p < 0.001), & negatively correlated with GFR, C3, C4 (p < 0.001). B2M predicted lupus LN https://t.co/XujdKvjjoS https://t.co/vl8XXQDhXM