Association between tubulointerstitial CD8+T cells and renal prognosis in lupus nephritis

Objective: Inflammatory cell infiltration is a pathological change commonly seen in renal biopsies from patients with lupus nephritis (LN), but its clinical correlation with clinical parameters and prognosis is unclear. Methods: Included in this retrospective study were 197 patients with ISN/RPS Class III-V LN, in whom renal biopsy was performed to analyze the histological pattern. Tubulointerstitial infiltrates were quantitated by standard histochemical staining. Clinical and histologic variables were evaluated using a Cox proportional hazards model. End-stage renal disease (ESRD) progression was defined as a two-fold increase in serum creati-nine (SCr) after biopsy, GFR decreased over 40%, initiation of dialysis, transplantation, or death. Results: Of the 197 patients, 166 patients (84.3%) had proliferative LN. The number of tubulointerstitial in-filtrates was the lowest in LN patients with ISN/RPS class V, and the number of CD68+ macrophages was the highest in all ISN/RPS classes of LN. In addition, the number of CD8+T cell infiltrates was positively correlated the SLEDAI sore, SCr level, proteinuria, the ratio of glomerulosclerosis and the degree of tubulointerstitial inflammation, interstitial fibrosis and tubular atrophy, activity and chronicity indices, and negatively correlated with C3 level at presentation. Multivariate survival analysis showed that tubulointerstitial CD8 + T cells > 130/ mm(2) was associated with ESRD progression (HR 1.007; 95% CI 1.003 to 1.011; p < 0.001). Conclusion: Tubulointerstitial CD8+T cells correlate with clinicohistologic impairment in LN. Tubulointerstitial CD8+T cells > 130/mm(2) is independently associated with an unfavorable long-term kidney outcome.