Weibo Le

Long-term renal survival and related risk factors in patients with IgA nephropathy: results from a cohort of 1155 cases in a Chinese adult population

BACKGROUND We sought to identify the long-term renal survival rate and related risk factors of progression to renal failure in Chinese adult patients with IgA nephropathy (IgAN) and to quantify the effects of proteinuria during the follow-up on outcome in patients with IgAN. METHODS Patients with biopsy-proven primary IgAN in the Nanjing Glomerulonephritis Registry were studied. Renal survival and the relationships between clinical parameters and renal outcomes were assessed. RESULTS One thousand one hundred and fifty-five patients were enrolled in this study. The 10-, 15- and 20-year cumulative renal survival rates, calculated by Kaplan-Meier method, were 83, 74 and 64%, respectively. At the time of biopsy, proteinuria>1.0 g/day [hazard ratio (HR) 3.2, P<0.001], estimated glomerular filtration rate (eGFR)<60 mL/min/1.73 m2 (HR 2.6, P<0.001), hypertension (HR 1.9, P<0.001), hypoproteinemia (HR 2.0, P<0.001) and hyperuricemia (HR 2.1, P<0.001) were the independent risk factors. Multivariate Cox analysis showed the time-average proteinuria (TA-P) during follow-up was the most important risk factor of renal failure. Patients with TA-P>1.0 g/day were associated with a 9.4-fold risk than patients with TA-P<1.0 g/day (P<0.001) and 46.5-fold risk than those with TA-P<0.5 g/day (P<0.001). Moreover, patients who achieved TA-P<0.5 g/day benefit much more than those with TA-P between 0.5 and 1.0 g/day (HR 13.1, P<0.001). CONCLUSIONS Thirty-six percent of Chinese adult patients with IgAN progress to end stage renal disease within 20 years. Five clinical features-higher proteinuria, hypertension, impaired renal function, hypoproteinemia and hyperuricemia-are independent predictors of an unfavorable renal outcome. The basic goal of anti-proteinuric therapy for Chinese patients is to lower proteinuria<1.0 g/day and the optimal goal is to lower proteinuria to <0.5 g/day.

A multicenter application and evaluation of the oxford classification of IgA nephropathy in adult chinese patients.

BACKGROUND The Oxford classification of immunoglobulin A (IgA) nephropathy (IgAN) provides a histopathologic grading system that is associated with kidney disease outcomes independent of clinical features. We evaluated the Oxford IgAN classification in a large cohort of patients from China. STUDY DESIGN Retrospective study. SETTING & PARTICIPANTS 1,026 adults with IgAN from 18 referral centers in China. Inclusion criteria and statistical analysis were similar to the Oxford study. PREDICTORS Histologic findings of mesangial hypercellularity score, endocapillary proliferation, segmental sclerosis or adhesion, crescents, necrosis, and tubular atrophy/interstitial fibrosis. Clinical features, blood pressure, estimated glomerular filtration rate (eGFR), proteinuria, and treatment modalities. OUTCOMES Time to a 50% reduction in eGFR or end-stage renal disease (the combined event); the rate of eGFR decline (slope of eGFR); proteinuria during follow-up. RESULTS Compared with the Oxford cohort, the Chinese cohort had a lower proportion of patients with mesangial hypercellularity (43%) and endocapillary proliferation (11%), higher proportion with segmental sclerosis or adhesion (83%) and necrosis (15%), and similar proportion with crescents (48%) and tubular atrophy/interstitial fibrosis (moderate, 24%; severe, 3.3%). During a median follow-up of 53 (25th-75th percentile, 36-67) months, 159 (15.5%) patients reached the combined event. Our study showed that patients with a mesangial hypercellularity score higher than 0.5 were associated with a 2.0-fold (95% CI, 1.5-2.8; P<0.001) higher risk of the combined event than patients with a score of 0.5 or lower. Patients with tubular atrophy/interstitial fibrosis of 25%-50% and >50% versus <25% were associated with a 3.7-fold (95% CI, 2.6-5.1; P<0.001) and 15.1-fold (95% CI, 9.5-24.2; P<0.001) higher risk of the combined event, respectively. Endocapillary proliferation, glomerular crescents, and necrosis were not significant. LIMITATIONS Retrospective study; the therapeutic interventions were miscellaneous. CONCLUSIONS We confirmed the associations of mesangial hypercellularity and tubular atrophy/interstitial fibrosis with kidney disease outcomes.

Renal histologic changes and the outcome in patients with diabetic nephropathy

BACKGROUND The progression of diabetic nephropathy (DN) is frequently determined by clinical parameters; however, the predictive value of histologic lesions remains largely unknown. Our aim was to evaluate the relationship between histologic changes and renal outcome in patients with type 2 diabetes mellitus (T2DM). METHODS A total of 396 patients with T2DM and biopsy-proven DN who received follow-up for at least 1 year were recruited. The severity of different histologic lesions was assessed using the pathologic classification established by the Renal Pathology Society. Renal outcomes were defined by progression to end-stage renal disease and doubling of serum creatinine. The influence of histologic findings on renal outcomes was assessed using univariate and multivariate Cox regression. RESULTS A univariate Cox regression showed that the severity of glomerular and interstitial lesions had a significant impact on renal outcomes (P < 0.001). Scores of vascular lesions demonstrated no association with renal outcomes (P > 0.05). A multivariate COX analysis demonstrated that the glomerular classes and scores of interstitial fibrosis and tubular atrophy were significantly associated with renal outcomes when adjusting for baseline proteinuria, mean arterial pressure and estimated glomerular filtration rate (P < 0.05). The glomerular and interstitial lesions correlated significantly among each other. However, in several patients, the severity of interstitial lesions did not correlate with glomerular lesions. CONCLUSION These findings indicated that the severity of glomerular and interstitial lesions were significantly associated with renal outcomes in patients with DN, whereas the vascular indexes did not have any impact on renal outcomes.

Validation of the Oxford classification of IgA nephropathy for pediatric patients from China

BackgroundThe Oxford classification of IgA nephropathy (IgAN) provides a useful tool for prediction of renal prognosis. However, the application of this classification in children with IgAN needs validation in different patient populations.MethodsA total of 218 children with IgAN from 7 renal centers in China were enrolled. The inclusion criteria was similar to the original Oxford study.ResultsThere were 98 patients (45%) with mesangial proliferation (M1), 51 patients (23%) with endocapillary proliferation (E1), 136 patients (62%) with segmental sclerosis/adhesion lesion (S1), 13 patients (6%) with moderate tubulointerstitial fibrosis (T1 26-50% of cortex scarred), and only 2 patients (1%) with severe tubulointerstitial fibrosis (T2, >50% of cortex scarred). During a median follow-up duration of 56 months, 24 children (12.4%) developed ESRD or 50% decline in renal function. In univariate COX analysis, we found that tubular atrophy/interstitial fibrosis (HR 4.3, 95%CI 1.8-10.5, P < 0.001) and segmental glomerulosclerosis (HR 9.2 1.2-68.6, P = 0.03) were significant predictors of renal outcome. However, mesangial hypercellularity, endocapillary proliferation, crescents, and necrosis were not associated with renal prognosis. In the multivariate COX regression model, none of these pathologic lesions were shown to be independent risk factors of unfavorable renal outcome except for tubular atrophy/interstitial fibrosis (HR 2.9, 95%CI 1.0-7.9 P = 0.04).ConclusionsWe confirmed tubular atrophy/interstitial fibrosis was the only feature independently associated with renal outcomes in Chinese children with IgAN.

Combined Assessment of Phospholipase A2 Receptor Autoantibodies and Glomerular Deposits in Membranous Nephropathy

Serum phospholipase A2 receptor antibodies (SAbs) and glomerular phospholipase A2 receptor antigen (GAg) deposits have been observed in idiopathic membranous nephropathy (IMN). However, the clinical application of these two biomarkers, particularly GAg deposition, needs to be further evaluated. We measured SAb concentration by ELISA and GAg deposition by immunofluorescence in 572 patients with biopsy-proven IMN. Overall, 68.5% of patients (392 of 572) had detectable SAb (SAb+), and 98.7% of patients who were SAb+ (387 of 392) and 70.6% of patients who were SAb- (127 of 180) had GAg deposition (GAg+). Compared with patients who were SAb-/GAg+, patients who were SAb+/GAg+ exhibited higher levels of proteinuria (P<0.001) and a lower chance of proteinuria remission (P<0.001). In 52 patients who underwent repeat biopsies, patients who did not achieve remission had a higher SAb+ rate on the first biopsy than patients who went into remission (P=0.001). Furthermore, SAb+ levels persisted in patients who did not achieve remission but significantly decreased in patients who achieved remission by the second biopsy. Patients who did not achieve remission also had a higher GAg+ rate on the first biopsy than patients who achieved remission (P<0.01). Sustained GAg+ deposits correlated with disease relapse. In conclusion, combining the measurements of SAb levels and detection of GAg deposition may provide additional information regarding diagnoses, treatment response, and disease relapse in patients with IMN.

Long-term renal outcomes in a cohort of 1814 Chinese patients with biopsy-proven lupus nephritis.

In the present study, we observed the renal outcomes in a cohort of 1814 Chinese patients with biopsy-proven lupus nephritis (LN) and evaluated the risk factors associated with poor renal prognosis. The 5 -, 10 -, 15 - and 20-year renal survival rates were 93.1%, 87.9%, 81.0% and 68.3%, respectively. Gender, LN duration, mean arterial pressure (MAP), proteinuria, serum creatinine, haemoglobin and pathological classification at the time of biopsy were independent risk factors for end-stage renal disease (ESRD). The long-term renal outcomes of patients with class II LN were unfavorable as opposed to those with class V. Additionally, the time-average proteinuria (TA-Pro) and the time-average mean arterial pressure (TA-MAP) during the follow-up were important risk factors for ESRD, with better predictive values than the baseline proteinuria and MAP. The results underscore the need for proteinuria and blood pressure control during follow-up in patients with LN; proteinuria levels should be controlled at least to < 1.0 g/24 h, and optimally to < 0.5 g/24 h; MAP should not exceed 96.5 mmHg. More attention should be paid to class II LN and emphasis should be placed on recurrence prevention of class II LN.

The spectrum of biopsy-proven kidney diseases in elderly Chinese patients

BACKGROUND Studies on biopsy-proven renal disease in the elderly (age ≥65 years) are extremely limited in China. The aim of this study was to examine the spectrum of renal diseases and their clinical presentations in elderly patients undergoing renal biopsy. METHODS All native renal biopsies (n = 851) performed in patients aged ≥65 years from January 2003 to December 2012 were retrospectively analyzed. The results were compared with a control group of 28 574 patients aged 18-64 years undergoing renal biopsy over the same period. RESULTS These 851 patients included 549 males and 302 females. Primary glomerular diseases (53.94%) occurred more frequently than secondary glomerular diseases (36.49%). The clinical manifestations were nephrotic syndrome (NS) in 29.49% of the patients, chronic renal failure in 24.68%, proteinuria and hematuria in 13.28%, proteinuria in 10.93%, acute kidney injury (AKI) in 10.81% and AKI and NS in 8.93%. Membranous nephropathy (MN) was the most frequent diagnosis (28.79%), followed by diabetic nephropathy (DN, 9.75%), IgA nephropathy (IgAN, 9.64%) and vasculitis (6.82%). When compared with the control group, the results showed that MN (P < 0.0001), DN (P < 0.0001), vasculitis (P < 0.0001) and amyloidosis (P < 0.0001) occurred more frequently and IgAN (P < 0.0001), lupus nephritis (P < 0.0001) and minimal change disease (P < 0.0001) occurred less frequently in the elderly. CONCLUSION This study is the first and largest renal biopsy series to analyze patients aged ≥65 years in China, and the results obtained from this study may increase the knowledge of renal diseases in elderly patients.

HLA-DRB1*15:01 and HLA-DRB3*02:02 in PLA2R-Related Membranous Nephropathy

Idiopathic membranous nephropathy (MN) is associated with HLA; however, the HLA allele involved remains unknown. To identify the HLA risk alleles associated with phospholipase A2 receptor (PLA2R)-related MN in the Chinese population, we sequenced the entire MHC region in DNA samples from 99 patients with PLA2R-related MN, 50 patients with PLA2R-unrelated MN, and 100 healthy subjects. Two HLA risk alleles, HLA-DRB1*15:01 and HLA-DRB3*02:02, independently and strongly associated with an increased risk of PLA2R-related MN. After adjusting for HLA-DRB1*15:01 and HLA-DRB3*02:02, no other alleles showed significant association with PLA2R-related MN. A replication study in an independent cohort of 293 participants with PLA2R-related MN and 285 healthy controls validated these findings. In a joint analysis, a multivariate logistic regression model confirmed that HLA-DRB1*15:01 (odds ratio [OR], 24.9; 95% confidence interval [95% CI], 15.3 to 42.6; P=2.3×10-35) and HLA-DRB3*02:02 (OR, 17.7; 95% CI, 11.0 to 30.3; P=8.0×10-29) independently and strongly associated with PLA2R-related MN. As many as 98.7% of patients with PLA2R-related MN, compared with 43.9% of control subjects, carried at least one HLA risk allele. Subjects with either risk allele had higher odds of developing PLA2R-related MN than those without a risk allele (OR, 98.9; 95% CI, 44.4 to 281.7; P=2.5×10-23). These HLA risk alleles also associated with the age at disease onset in patients with PLA2R-related MN. In conclusion, our findings provide clear evidence that the HLA-DRB1*15:01 and HLA-DRB3*02:02 alleles independently and strongly associate with PLA2R-related MN in the Chinese population.

Long-Term Outcome of IgA Nephropathy Patients with Recurrent Macroscopic Hematuria

Background/Aims: The long-term renal outcomes of patients with IgA nephropathy (IgAN) who present with recurrent macroscopic hematuria (RMH) have not been described in previous studies. Methods: Patients with biopsy-proven primary IgAN in Jinling Hospital were divided into three groups according to different patterns of macroscopic hematuria (MH): RMH, isolated MH (IMH), and those without a history of MH (NMH). Results: A total of 1,155 patients were enrolled in the study (158 in the RMH group, 256 in the IMH group, and 741 in the NMH group). At biopsy, patients with RMH were younger, had lower median proteinuria, a lower incidence of hypertension, and a higher estimated glomerular filtration rate than those in the NMH group. Pathologically, patients with RMH had a lower level of mesangial hypercellularity and segmental glomerulosclerosis as well as less tubular atrophy than those with NMH. The demographic and clinical features of patients with IMH fell between patients with RMH and those with NMH. During a median follow-up of 7.9 years, the 5-, 10- and 20-year cumulative renal survival after biopsy, as calculated by K-M methods, were 98, 91, and 91% in the RMH group, 95, 89, and 64% in the IMH group, and 95, 79, and 57% in the NMH group. The renal survival in patients with RMH was significantly better than patients with NMH or IMH. Conclusions: The long-term prognosis of patients who present with RMH is significantly better than patients with NMH or IMH.

Comparison between patients with IgA nephropathy with minimal change disease and patients with minimal change disease

OBJECTIVE To compare the clinicopathological characteristics, treatment response, and prognosis between patients with IgAN nephropathy with minimal change disease (MCD-IgAN) and patients with minimal change disease (MCD). METHODS 77 patients with biopsy-proven MCD-IgAN from the Jinling Hospital IgAN Registry and 77 patients with MCD followed up for ≥ 3 years were retrospectively reviewed. RESULTS MCD-IgAN and MCD patients had similar clinical presentations, both were predominantly young males, the disease mainly manifested as nephrotic syndrome, and the patients rarely presented with microscopic hematuria. Compared with the MCD group, patients with MCD-IgAN had lower levels of baseline serum albumin (p < 0.01) and eGFR (p < 0.05), a higher level of urine n-acetylglucosaminidase (p < 0.01), higher proportion of mesangial hypercellularity (M1), and more severe acute tubulointerstitial lesions in renal pathology (p < 0.01, p < 0.01, respectively). After 8 weeks of corticosteroid therapy, no significant differences were observed in the rate of complete remission, partial remission, and no remission between MCDIgAN and MCD patients (88.3% vs. 90.9%, 10.4% vs. 5.2%, 1.3% vs. 3.9%, p > 0.05). The median time to achieve remission was 4 weeks (range 1 - 24 weeks) and 4 weeks (range 1 - 28 weeks), respectively. No significant difference existed in the efficacy of corticosteroid between the two groups. During 3.96 years (range 3.0 - 8.5 years) of follow-up, no patients in the two groups entered end-stage renal disease (ESRD), only 2 patients (2.6%) with MCD-IgAN had > 50% reduction of eGFR. CONCLUSIONS MCD-IgAN may be controlled well achieving a comparable clinical outcome as MCD but more frequently necessitates additional immunosuppressive medication.