ABSTRACT
Objective:To study the clinicopathological characteristics, treatment and prognosis in lupus nephritis (LN) patients with renal thrombotic microangiopathy (TMA), so as to provide more theoretical basis for clinicians to recognize and treat this disease.Methods:The clinical data of LN patients who underwent renal biopsy in the First Affiliated Hospital of Zhengzhou University from January 1, 2012 to May 31, 2019 were retrospectively collected and analyzed. According to renal clinicopathological examination, the patients were divided into renal TMA group and non-renal TMA group. The clinical data, laboratory examination, renal pathological examination, therapeutic measures and prognostic between the two groups were compared. Follow-up end points were defined as composite ends, including all-cause death, entry into end-stage renal disease, and estimated glomerular filtration rate decrease>50% of baseline. Kaplan-Meier survival curve and log-rank test were used to compare the difference of survival rate between the two groups, and multivariate Cox regression equation was used to analyze the risk factors of endpoint events in LN patients.Results:A total of 1 133 patients with LN were enrolled in this study. Patients with renal TMA were more likely to have hypertension ( χ2=16.310, P<0.001), higher baseline serum creatinine ( Z=-6.918, P<0.001) and 24-hour urine protein ( Z=-2.232, P=0.026), and higher renal pathology activity index (AI) score ( Z=1.957, P=0.001)and chronic index (CI) score ( Z=1.836, P=0.002). The proportions of hormone shock ( P<0.001) and plasma exchange ( P<0.001) in the renal TMA group were higher than those in non-renal TMA group. After treatment of (12±2) months, patients in the renal TMA group had a lower complete response rate ( χ2=10.455, P=0.001) and a higher non-response rate ( χ2=6.047, P=0.014) than those in non-renal TMA group, and were associated with worse prognosis (Log-rank test χ2=26.490, P<0.001). Renal TMA was an independent risk factor for poor prognosis ( HR=2.347, 95% CI 1.210-4.553, P=0.012). Conclusions:Compared with LN patients without renal TMA, LN patients with renal TMA are more likely to have hypertension, with higher serum creatinine, 24-hour urinary protein, AI and CI, suggesting poorer treatment response and renal prognosis. Moreover, renal TMA is an independent risk factor for poor prognosis in patients with LN.