Non-Albumin Proteinuria in Lupus Nephritis with Tubulointerstitial Inflammation and its Clinical Significance

Abstract

Background: Tubulointerstitial inflammation (TI) associated with systemic lupus erythematosis is an increasing finding in lupus nephritis. TI severity may have prognostic significance in the renal outcomes of lupus nephritis. Here, we aimed to determine whether non-albumin proteinuria is associated with TI severity and with the renal response in lupus nephritis. Objective: To investigate the possible association between non-albumin proteinuria, tubulointerstial inflammation severity and poor renal response after immunosuppressive treatment. Patients and Methods: This is a case series study which was conducted on 100 patients with systemic lupus erythematosis recruited from the outpatient clinic of Clinical Immunology at Ain Shams University Hospitals. Subject ages were between 13-53 years old, each one was subjected to detailed history, physical examination, laboratory investigations including serum creatinine before and after treatment, protein /creatinine ratio before and after treatment, albumin /creatinine ratio, ESR, CRP, CBC, C3 C4, anti -DNA, eGFR and renal biopsy Results: Our results showed that non-albumin proteinuria (uPCR − uACR) was significantly higher in patients with moderate-to-severe TI than in patients with no-to-mild TI. Further, higher uPCR − uACR levels at baseline were associated with poor renal response after 6 months of treatment. Conclusion: we found that non-albumin proteinuria (uPCR-uACR) is associated with severe tubulointerstitial inflammation (TI) in lupus nephritis.