CALR and lupus nephritis: Work-up revealed leukopenia (WBC 2.5 10e9/L), hypocomplementemia (C3 0.23 g/L), positive anti-nuclear antibody, anti-dsDNA (633 IU/ml; normal less than10), anti-SSa/Ro, and anti-Smith antibodies, Class II lupus nephritis and a SLEDAI of 29.