Histopathological indicators of disease outcome in class IV lupus nephritis: a revisit of various indices

Outcome of biopsy-proven lupus nephritis with low glomerular filtration rate at presentation

OBJECTIVES

Currently, there is limited data regarding the outcomes of lupus nephritis (LN) with moderate to severe renal failure at presentation (defined by low glomerular filtration rate; GFR <30 mL/min).

METHODS

Sixty-four patients with biopsy-proven LN and estimated GFR (eGFR) <30 mL/min were prospectively analyzed. Outcome measure of persistently low eGFR, end-stage renal disease (ESRD) or death at 365 days were grouped as Major Adverse Kidney Events (MAKE365).

RESULTS

Diagnosis of lupus was simultaneous with onset of renal disease in 60% of cases. Histologically, 82.3% (n = 51) were class IV, the median serum creatinine was 4 mg/dL (interquartile range [IQR] 3.1-5.9 mg/dL), median eGFR was 13.75 mL/min (IQR 9.25-19 mL/min) and 42.2% (n = 27) required dialysis at presentation. Induction regimens included National Institute of Health (68.2%), Eurolupus protocol (10.9%) and mycophenolate mofetil (8%). Over 365 days, 23 (37.5%) subjects died, while 41 (62.5%) survived. The majority of deaths were due to infection and sepsis (14/23). Among the survivors, 70.7% had good renal outcome, 12.1% had persistently low GFR (<30 mL/min), while 17% developed ESRD. In this group, treatment response rate was 84.6% (complete response 25.6%, partial response 59%). Those with a better renal function at presentation had a good treatment response (100% vs. 40%). Altogether, n = 35 (54.6%) were included in the MAKE365 category. Between the renal survival group (n = 29) versus the MAKE365 group (n = 35) there was no difference in clinical or histological parameters.

CONCLUSION

The current treatment protocols had a good response rate in patients with LN even with severe kidney injury at presentation. However, the risk of serious infections and subsequent mortality was high.

miR-152 Attenuates the Severity of Lupus Nephritis Through the Downregulation of Macrophage Migration Inhibitory Factor (MIF)-Induced Expression of COL1A1

Background: The role of miR-152 in lupus nephritis has not been elucidated. The aim of this study was to investigate the role of miR-152 in the pathogenesis of lupus nephritis (LN).

Methods: miR-152 expression was detected using RT-PCR in LN tissue and normal controls. The miR-152 expression was compared with clinical parameters such as 24 h urine protein excretion level, serum creatinine, and serum complement level and SLEDAI score. The function of miR-152 was examined using human renal proximal tubular epithelial cells (HRPTE). miR-152 mimics and inhibitors were transfected to HRPTEs to ascertain the effects of miR-152.

Results: miR-152 expression was downregulated in LN tissue. There was an inverse correlation between miR-152 expression in LN tissue and clinical parameters like 24 h urine protein excretion levels and serum creatinine, but not serum complement levels or SLEDAI. Further analysis showed that macrophage migration inhibitory factor (MIF) was a direct target of miR-152. Downregulation of MIF through complementary binding of miR-152 inhibited the renal expression of COL1A1.

Conclusion: miR-152 expression was tapered in LN tissue and miR-152 expression was inversely correlated with chronicity index (CI), serum creatinine and severity of proteinuria. miR-152 may attenuate the severity of LN through the downregulation of MIF-induced expression of COL1A1. These findings suggest that miR-152 may be a potential target for the treatment of LN.

The Impact of Baseline Serum Creatinine on Complete Remission Rate and Long-Term Outcome in Patients with Severe Lupus Nephritis

BACKGROUND/AIM

We assess the impact of serum creatinine at baseline on complete remission rate and long-term outcome in severe lupus nephritis (SLN).

METHODS

A total of 86 adult patients with SLN [International Society of Nephrology/Renal Pathology Society (ISN/RPS) class IV lesions] were evaluated based on baseline serum creatinine levels (≤1.0, 1.01-1.5, 1.51-2.0, 2.01-3.0, and >3.0 mg/dl; n = 22, 23, 16, 12, and 13, respectively). The complete remission rates (serum creatinine level of ≤1.4 mg/dl and proteinuria of ≤0.33 g/day) and long-term outcomes (stable renal function, dialysis, and death) were compared. The patients were followed for 121 ± 64 months.

RESULTS

The baseline clinical features were similar, but the chronicity index was significantly higher with increasing levels of serum creatinine. Complete remission rates were significantly higher in patients with lower levels of serum creatinine (86 vs. 52 vs. 19 vs. 25 vs. 0%, p < 0.0001). Patients with a baseline serum creatinine level of ≤1.0 mg/dl were >16 times as likely (OR 16.2; 95% CI: 4.2-61.5) to attain a complete remission and >6 times as likely (OR 6.1; 95% CI: 1.9-18.6) to have stable renal function at the last follow-up as compared to patients with a serum creatinine level of >1.0 mg/dl. The 15-year renal survival rate was greatest among those patients with a baseline serum creatinine level of ≤1.0 mg/dl (76 vs. 57 vs. 48 vs. 25 vs. 10%, p < 0.0001).

CONCLUSION

The prognosis of SLN is significantly affected by the serum creatinine level at baseline. The complete remission rate is highest, and the long-term prognosis most favorable, in patients with a baseline serum creatinine level of ≤1.0 mg/dl. This emphasizes the importance of early diagnosis and treatment.