CRP and Decreased total leukocyte count: In addition, we analyzed the difference of the lab tests at admission between two groups, and we found that the IDA group had more patients with leukopenia (48.4% vs. 41.3%, P = 0.044), increased C-reactive protein (41.5% vs. 33.6%, P = 0.020), positive anti-dsDNA (56.7% vs. 44.4%, P < 0.001), and hypocomplementemia (78.8% vs. 69.2%, P = 0.002), less with increased serum creatinine (6.0% vs. 11.5%, P = 0.004) and abnormal glomerular filtration rate (17.8% vs. 26.2%, P = 0.003).