Changes in the urinary excretion of β2-microglobulin (β2MG) and N-acety-β-D-glucosaminidase (NAG) during treatment for lupus nephritis

Tubulointerstitial involvement in the kidneys is frequently found but it is a less emphasized feature of lupus nephritis (LN). Recent studies have shown increases in the urinary excretion of beta 2-microglobulin (beta 2 MG) and N-acetyl-beta-D-glucosaminidase (NAG), which are considered to indicate the presence of tubulointerstitial damage, particularly in cases of LN. However, the changes in these urinary parameters during the clinical course of LN have not yet been fully clarified. In this report, we describe the changes in the urinary excretion of beta 2MG and NAG during immunosuppressive treatment combined with double filtration plasmapheresis in a case of LN.