[Clinicopathological characteristics and prognosis of lupus nephritis patients with acute kidney disease].

Objective

To investigate the clinicopathological characteristics and prognosis of patients with lupus nephritis (LN) presenting with acute kidney disease (AKD).

Methods

A retrospective study was conducted on 1 136 patients diagnosed with LN via renal biopsy at the First Affiliated Hospital of Zhengzhou University between January 1, 2012, and May 31, 2019. Clinicopathological features, treatment regimens, and prognosis were compared between the AKD group and the non-AKD group among LN patients. Propensity score matching (1∶1 ratio, caliper=0.03) was used to balance differences in sex, age, Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score, and LN pathological class. Kaplan-Meier survival analysis and multivariate COX regression models were applied to evaluate the impact of AKD on patient prognosis. Additionally, a subgroup analysis was performed among the LN patients with AKD to assess the effect of renal recovery at the 6-month follow-up on long-term prognosis.

Results

The incidence of AKD among LN patients was 19.19% (218/1 136). In the LN with AKD group, 171 patients (78.44%) were female, and the median age was 29 (23, 43) years. Compared with patients without AKD, those with AKD exhibited a significantly higher prevalence of hypertension [52.75% (115/218) vs. 26.90% (247/918)], higher SLEDAI scores [8 (5, 12) vs. 5 (4, 10)], higher serum creatinine [153 (126, 210) μmol/L vs. 62 (51, 76) μmol/L], and higher 24-hour urine protein [3.96 (2.35, 6.70) g vs. 2.66 (1.35, 4.99) g, all P<0.05]. Patients with AKD also displayed higher renal pathological Activity Index [9 (5, 13) vs. 5 (2, 8)] and Chronicity Index scores [1 (0, 4) vs. 0 (0, 1)], alongside higher utilization rates of induction-phase glucocorticoid pulse therapy [5.96% (13/218) vs. 0.76% (7/918)], hemodialysis [1.83% (4/218) vs. 0.11% (1/918)], and plasma exchange [1.83% (4/218) vs. 0.22% (2/918)] (all P<0.05). After propensity score matching (205 patients per group), survival analysis showed that patients with AKD had lower short-term (6-month) and long-term survival rates than those without AKD (short-term: log-rank test χ2=31.64, P<0.001; long-term: log-rank test χ2=12.61, P<0.001). Multivariate COX regression analysis revealed that AKD was an independent risk factor for both poor short-term prognosis (HR=4.84, 95%CI 1.05-22.22, P=0.043) and poor long-term prognosis (HR=4.68, 95%CI 2.25-9.72, P<0.001) in patients with LN. Among patients with AKD, those who achieved renal recovery at the 6-month follow-up experienced a higher long-term survival rate than those who did not (log-rank test χ2=51.61, P<0.001).

Conclusions

The incidence of AKD is relatively high among patients with LN. Moreover, LN patients presenting with AKD exhibit more severe clinical and pathological manifestations, resulting in worse short-term and long-term prognoses. Early renal recovery contributes to improved long-term outcomes in this population.