Association of podocyte injury with clinical features and prognosis in patients with mesangial proliferative lupus nephritis.

OBJECTIVES
The aim of this study is to explore the association of podocyte injury with clinical features and outcomes in mesangial proliferative (Class II) lupus nephritis (LN).


METHODS
We conducted a retrospective and clinicopathologic analysis with 576 LN patients with renal biopsy and screened 58 patients with Class II LN. Then, the 58 cases were divided into 4 groups based on the degree of podocyte damage and immune complex (IC) deposits on light microscope (histological and immunofluorescence) and electron microscope: Podocyte Injury Group, IC deposits Group, Podocyte Injury and IC Group, and Less-lesion Group. Clinical and pathologic information was collected from the patients' medical records at the time of the kidney biopsy and at follow-up. The data of demography, clinical parameters, therapy, remission, and relapse rates were analyzed and compared across groups.


RESULTS
A significant difference was observed in the ages of patients among four Class II LN groups. The onset age of patients with FPE ≥ 50% was significant later. The frequency of thrombocytopenia was statistically different among the four groups and the patients with FPE ≥ 50% had lower frequency of thrombocytopenia. Patients with FPE ≥ 50% had lower serum albumin, eGFR, and elevated proteinuria and serum lipids. In this study, most patients received glucocorticoids in combination with immunosuppressants. Among the 4 groups, the use of ACEI/ARBs was highest in the podocyte injury group. There was a statistical difference in the renal relapse rates among the 4 Class II LN groups. Moreover, the recurrence rate was higher in the FPE ≥ 50% group.


CONCLUSION
Our data identified Class II LN patients with podocyte injury (FPE ≥ 50%) present prominent renal damage and higher rate of renal relapse, suggesting more aggressive treatment and close follow-up for these patients.