Proteinuria during Follow-Up Period and Long-Term Renal Survival of Childhood IgA Nephropathy

Background

Proteinuria is the most important risk factor for IgA nephropathy progression. The purpose of this study is to evaluate the long-term outcome and risk factors for poor prognosis in childhood IgA nephropathy.

Methods

Patients who were diagnosed with IgA nephropathy between 1972 and 1992 at the Tokyo Metropolitan Kiyose Children’s Hospital were included. We analyzed risk factors for progression to end-stage kidney disease (ESKD) and chronic renal insufficiency (CRI) using Kaplan-Meier method and multivariate analyses of Cox proportional hazard model.

Results

One hundred patients were included and the median observation period was 11.8 years. Twelve and 17 patients progressed to ESKD and CRI, respectively. The survival probabilities were 90.0% at 10 years and 79.8% at 20 years for ESKD, and 86.1% at 10 years and 72.3% at 20 years for CRI. Notably, patients with heavy proteinuria with hypoalbuminemia during follow-up period showed extremely poor prognosis. In this group, the survival rate at 10 years from ESKD and CRI was 40.6% and 20.8%, respectively. By multivariate analysis, proteinuria at diagnosis and proteinuria during follow-up period were risk factors for ESKD, whereas glomeruli showing mesangial proliferation ≥50% and proteinuria during follow-up period were risk factors for CRI. Patients without heavy proteinuria during follow-up period did not develop CRI and 63% of patients with mild proteinuria during follow-up period showed no proteinuria at the last observation.

Conclusions

The degree of proteinuria during follow-up period is the strongest risk factor for ESKD and CRI.     

Significance of Urinary Full-Length Megalin in Patients with IgA Nephropathy

Background and Objectives

Megalin is highly expressed at the apical membranes of proximal tubular epithelial cells. A urinary full-length megalin (C-megalin) assay is linked to the severity of diabetic nephropathy in type 2 diabetes. This study examined the relationship between levels of urinary C-megalin and histological findings in adult patients with IgA nephropathy (IgAN).

Design, Setting, Participants, & Measurements

Urine samples voided in the morning on the day of renal biopsy were obtained from 73 patients with IgAN (29 men and 44 women; mean age, 33 years) and 5 patients with membranous nephropathy (MN). Renal pathologic variables were analyzed using the Oxford classification of IgAN, the Shigematsu classification and the Clinical Guidelines of IgAN in Japan. The levels of urinary C-megalin were measured by sandwich ELISA.

Results

Histological analysis based on the Oxford classification revealed that the levels of urinary C-megalin were correlated with mesangial hypercellularity in IgAN patients (OR = 1.76, 95% CI: 1.04–3.27, P<0.05). There was a significant correlation between the levels of urinary C-megalin and the severity of chronic extracapillary abnormalities according to the Shigematsu classification in IgAN patients (β = 0.33, P = 0.008). The levels of urinary C-megalin were significantly higher in all risk levels of IgAN patients requiring dialysis using the Clinical Guidelines of IgAN in Japan than in the control group. The levels of urinary C-megalin were significantly higher in the high risk and very high risk grades than in the low risk grade (P<0.05). The levels of urinary C-megalin were significantly higher in MN patients compared to the control group.

Conclusions

The levels of urinary C-megalin are associated with histological abnormalities in adult IgAN patients. There is a possibility that urinary C-megalin is an independent predictor of disease progression of IgAN. In addition, our results suggest that urinary C-megalin is a marker of glomerular abnormalities in various glomerular diseases as well as IgAN.     

双倍剂量氯沙坦治疗IgA肾病中蛋白尿疗效评价

目的：探讨双倍剂量氯沙坦氯沙坦在IgA肾病（IgA nephropathy,teAN）中降低蛋白尿的临床疗效。方法：选取40例经肾穿刺病理诊断为IgAN的患者,随机分为2组,A组18例采用单剂量（50mg,qd）氯沙坦;B组22例用双倍剂量（100mg,qd）氯沙坦,观察8周后两组的血压、实验室指标：血肌酐、尿素氮、血钾、24h尿蛋白、内生肌酐清除率（creatinine clearancerate,CCr）等以及临床症状,并作安全性评价。结果：B组患者24h蛋白尿下降（0．91±0．33g／24h）,A组患者蛋白尿下降（0．21±0．22g／24h）,B组24h蛋白尿下降率明显高于A组（P〈0．05）。双倍剂量氯沙坦在IgAN治疗中未出现不良反应,包括高血钾、咳嗽、低血压或水肿等。结论：双倍剂量氯沙坦在治疗IgAN中降蛋白尿的疗效较单剂量明显,应用安全,耐受性好,无明显不良反应。     

孢素联合糖皮质激素对IgA肾病患者IgA、C3及IgA/C3影响研究

目的:探讨孢素联合糖皮质激素对IgA肾病患者IgA、C3及IgA/C3的影响。方法:我院收治的IgA肾病住院患者90例,按用药不同分为对照组与实验组。对照组予以醋酸泼尼松片口服,实验组在对照组基础上予以予环孢素软胶囊口服,治疗结束后对患者的血肌酐、血尿酸、24 h尿蛋白定量及IgA、C3、IgA/C3进行检测。结果:与对照组相比,实验组24 h尿蛋白定量水平较低,P0.05;IgA水平及IgA/C3水平较低,P0.05,差异具有统计学意义;两组患者的C3、血肌酐、血尿酸水平无显著差异,无统计学意义(P0.05)。结论:孢素联合糖皮质激素能够显著降低Ig A肾病患者Ig A水平及IgA/C3,对C3水平无影响,对临床有指导意义。     

Tacrolimus Decreases Albuminuria in Patients with IgA Nephropathy and Normal Blood Pressure: A Double-Blind Randomized Controlled Trial of Efficacy of Tacrolimus on IgA Nephropathy

Background

Treatment remains uncertain for IgA nephropathy patients with mild to moderate proteinuria, for whom anti-hypertensive medication or the RAS blocker is not applicable due to low blood pressure.

Trial design

A double blinded randomized trial.

Methods

The anti-proteinuric effect of tacrolimus was explored for 40 biopsy-proven mild IgA nephropathies for 16 weeks. We randomly assigned patients either to receive tacrolimus or placebo with stratification by using a renin angiotensin system blocker. The primary outcome was the percentage change of final UACR compared to the baseline value (pcUACR).

Results

The mean value of pcUACR at 12-week and 16-week visits (primary outcome) was decreased more in the Tac group compared to the control group (–52.0±26.4 vs –17.3±29.3%, p = 0.001). At each visit, pcUACR was also decreased more in the Tac group compared to the control group. In the Tac group, the pcUACRs were –60.2±28.2%, –62.2±33.9%, –48.5±29.8%, and –55.5±24.0%, and, in the control group, –6.8±32.2%, –2.5±35.9%, –12.7±34.2%, and –21.9±30.6%, at 4-week, 8-week, 12-week, and 16-week visits, respectively. The pre-defined secondary outcomes were better in the Tac group compared to the control group. The frequency of decrease in pcUACR and percentage change of UPCR (pcUPCR) ≥50% at 16 weeks were 65.0% (13/20) and 55.0% (11/20)in the Tac group, and 25.0% (5/20) and 15.0% (3/20), in the control group, respectively (p = 0.025 for pcUACR and p = 0.019 for pcUPCR). However, tacrolimus wasn''t effective with a dose of 0.05 mg/kg/day in patients taking ARB. The adverse events were tolerable.

Conclusion

Tacrolimus effectively reduced proteinuria in IgA nephropathy with normal blood pressure. This suggested that tacrolimus could be an alternative to corticosteroid and RAS blocker for IgA nephropathy patients who cannot endure anti-hypertensive medication.

Trial Registration

Clinicaltrial.gov NCT1224028     

Rat Macrophages in Experimental IgA Nephropathy

To test whether the peripheral macrophage functions as an early index of oxygen free radical release in association with the development of IgA nephropathy (IgAN), we studied female Lewis rats. IgAN was produced by treatment over 8 weeks with 0.1% bovine gamma globulin (BGG) in drinking water, followed by three daily intravenous injections of BGG, 1 mg/dose. Fifteen rats were divided randomly into three groups: control, IgAN, and IgAN fed vitamin E 100 IU/kg chow. At the end of the treatment period, rats were placed in individual metabolic cages for 24-h urine collections and then anesthetized with Inactin (100 mg/kg BW) for aspiration of peritoneal macrophages. The results (means ± SD) extended our previous data in male rats, confirming that the elevated proteinuria of IgAN (3.62 ± 0.79 mg/day) was significantly reduced with vitamin E treatment (2.59 ± 0.28 mg/day) in female rats (P< 0.002) More importantly, we indicated for the first time that oxygen free radicals' production by peritoneal macrophages in IgAN was significantly reduced by vitamin E: 1.58 ± 0.91 nmol/10⁶cells/15 min in the untreated group vs 3.28 ± 0.54 nmol/10⁶cells/15 min in the vitamin E-treated group (P< 0.05).     

Uncoupling of Glomerular IgA Deposition and Disease Progression in Alymphoplasia Mice with IgA Nephropathy

Previous clinical and experimental studies have indicated that cells responsible for IgA nephropathy (IgAN), at least in part, are localized in bone marrow (BM). Indeed, we have demonstrated that murine IgAN can be experimentally reconstituted by bone marrow transplantation (BMT) from IgAN prone mice in not only normal mice, but also in alymphoplasia mice (aly/aly) independent of IgA⁺ cells homing to mucosa or secondary lymphoid tissues. The objective of the present study was to further assess whether secondary lymph nodes (LN) contribute to the progression of this disease. BM cells from the several lines of IgAN prone mice were transplanted into aly/aly and wild-type mice (B6). Although the transplanted aly/aly showed the same degree of mesangial IgA and IgG deposition and the same serum elevation levels of IgA and IgA-IgG immune-complexes (IC) as B6, even in extent, the progression of glomerular injury was observed only in B6. This uncoupling in aly/aly was associated with a lack of CD4⁺ T cells and macrophage infiltration, although phlogogenic capacity to nephritogenic IC of renal resident cells was identical between both recipients. It is suggested that secondary LN may be required for the full progression of IgAN after nephritogenic IgA and IgA/IgG IC deposition.     

前列地尔联合参芪扶正注射液对IgA肾病的临床疗效观察

目的:探讨前列地尔联合参芪扶正注射液治疗Ig A肾病的临床疗效。方法:选取2011年3月~2015年7月于我院就诊的Ig A肾病患者60例,按照随机数字表法将所有患者分为2组,每组各30例。对照组患者给予前列地尔,实验组患者在对照组的基础上联合使用参芪注射液。比较治疗前后两组患者血清胱抑素C、血肌酐、血尿素氮、血浆白蛋白及24小时尿蛋白水平,同时比较治疗结束后两组患者的临床总有效率。结果:治疗前相比,两组患者治疗后的血清胱抑素C、血肌酐、24小时尿蛋白水平均降低(P0.05);血浆白蛋白水平均升高(P0.05),且实验组患者血清胱抑素C、血肌酐、血尿素氮及24小时尿蛋白水平较对照组更低(P0.05),血浆白蛋白水平更高(P0.05)。与对照组相比,实验组患者临床总有效率较高(P0.05)。结论:前列地尔联合参芪扶正注射液能够提高Ig A肾病患者的临床总有效率,可能与升高血浆白蛋白水平有关。     

Mortality of IgA Nephropathy Patients: A Single Center Experience over 30 Years

Research on the prognosis of IgA nephropathy (IgAN) has focused on renal survival, with little information being available on patient survival. Hence, this investigation aimed to explore long-term patient outcome in IgAN patients. Clinical and pathological characteristics at the time of renal biopsy were reviewed in 1,364 IgAN patients from 1979 to 2008. The outcomes were patient death and end stage renal disease (ESRD) progression. Overall, 71 deaths (5.3%) and 277 cases of ESRD (20.6%) occurred during 13,916 person-years. Ten-, 20-, and 30-year patient survival rates were 96.3%, 91.8%, and 82.7%, respectively. More than 50% patient deaths occurred without ESRD progression. Overall mortality was elevated by 43% from an age/sex-matched general population (GP) (standardized mortality ratio [SMR], 1.43; 95% confidence interval [CI], 1.04–1.92). Men had comparable mortality to GP (SMR, 1.22; 95% CI, 0.82–1.75), but, in women, the mortality rate was double (SMR, 2.17; 95% CI, 1.21–3.57). Patients with renal risk factors such as initial renal dysfunction (estimated glomerular filgration rate <60 ml/min per 1.73m²; SMR, 1.70; 95% CI, 1.13–2.46), systolic blood pressure ≥140 mmHg (SMR, 1.88; 95% CI, 1.19–2.82) or proteinuria ≥1 g/day (SMR, 1.66; 95% CI, 1.16–2.29) had an elevated mortality rate. Patients with preserved renal function, normotension, and proteinuria <1 g/day, however, had a similar mortality rate to GP. When risk stratification was performed by counting the number of major risk factors present at diagnosis, low-risk IgAN patients had a mortality rate equal to that of GP, whereas high-risk patients had a mortality rate higher than that of GP. This investigation demonstrated that overall mortality in IgAN patients was higher than that of GP. Women and patients with renal risk factors had a higher mortality than that of GP, Therefore, strategies optimized to alleviate major renal risk factors are warranted to reduce patient mortality.     

Long-Term Follow-Up of Proteinuria and Estimated Glomerular Filtration Rate in HIV-Infected Patients with Tubular Proteinuria

Objective

The objective of this prospective observational study was to describe the evolution of tubular proteinuria detected in HIV-infected patients, and to evaluate the impact of tenofovir disoproxil fumarate (TDF) discontinuation.

Methods

Proteinuria and estimated glomerular filtration rate (eGFR) were followed during a median duration of 32 months, in 81 HIV-infected patients with tubular proteinuria and eGFR ≥ 60 ml/min/1.73 m² (determined using the Chronic Kidney Disease Epidemiology (CKD-EPI) Collaboration equation). Tubular proteinuria was defined by urine protein to creatinine ratio (uPCR) ≥200 mg/g and albumin to protein ratio (uAPR) <0.4.

Results

Twenty per cent of patients had persistence of tubular proteinuria: TDF continuation was the main factor associated with this persistence [OR 9.0; 95%CI: 1.9–41.4; p = 0.01]. Among the 23 patients who discontinued TDF, uPCR returned below the threshold of 200 mg/g in 11 patients. Overall, eGFR decreased with a mean rate of decline of 3.8 ml/min/1.73m²/year. The decline in eGFR was lesser after discontinuation of TDF (5.8 ml/min/1.73m²/year during TDF exposure versus 3 ml/min/1.73m²/year after TDF discontinuation; p = 0.01).

Conclusions

The continuation of TDF was the main factor associated with the persistence of proteinuria. Moreover, proteinuria was normalized in only half of the patients who discontinued TDF. The clinical significance of TDF-related low level of proteinuria as a factor associated with renal disease progression and bone loss remains poorly understood.     

DNA Methylation in Cosmc Promoter Region and Aberrantly Glycosylated IgA1 Associated with Pediatric IgA Nephropathy

IgA nephropathy (IgAN) is one of the most common glomerular diseases leading to end-stage renal failure. Elevation of aberrantly glycosylated IgA1 is a key feature of it. The expression of the specific molecular chaperone of core1ß1, 3galactosyl transferase (Cosmc) is known to be reduced in IgAN. We aimed to investigate whether the methylation of CpG islands of Cosmc gene promoter region could act as a possible mechanism responsible for down-regulation of Cosmc and related higher secretion of aberrantly glycosylated IgA1in lymphocytes from children with IgA nephropathy. Three groups were included: IgAN children (n = 26), other renal diseases (n = 11) and healthy children (n = 13). B-lymphocytes were isolated and cultured, treated or not with IL-4 or 5-Aza-2’-deoxycytidine (AZA). The levels of DNA methylation of Cosmc promotor region were not significantly different between the lymphocytes of the three children populations (P = 0.113), but there were significant differences between IgAN lymphocytes and lymphocytes of the other two children populations after IL-4 (P<0.0001) or AZA (P<0.0001). Cosmc mRNA expression was low in IgAN lymphocytes compared to the other two groups (P<0.0001). The level of aberrantly glycosylated IgA1 was markedly higher in IgAN group compared to the other groups (P<0.0001). After treatment with IL-4, the levels of Cosmc DNA methylation and aberrantly glycosylated IgA1 in IgAN lymphocytes were remarkably higher than the other two groups (P<0.0001) with more markedly decreased Cosmc mRNA content (P<0.0001). After treatment with AZA, the levels in IgAN lymphocytes were decreased, but was still remarkably higher than the other two groups (P<0.0001), while Cosmc mRNA content in IgAN lymphocytes were more markedly increased than the other two groups (P<0.0001). The alteration of DNA methylation by IL-4 or AZA specifically correlates in IgAN lymphocytes with alterations in Cosmc mRNA expression and with the level of aberrantly glycosylated IgA1 (r = −0.948, r = 0. 707). Our results suggested that hypermethylation of Cosmc promoter region could be a key mechanism for the reduction of Cosmc mRNA expression in IgAN lymphocytes with associated increase in aberrantly glycosylated IgA1.     

Assessment of Proteinuria in Patients with Chronic Kidney Disease Stage 3: Albuminuria and Non-Albumin Proteinuria

Background and Objective

Proteinuria assessment is key in investigating chronic kidney disease (CKD) but uncertainty exists regarding optimal methods. Albuminuria, reflecting glomerular damage, is usually measured, but non-albumin proteinuria (NAP), reflecting tubular damage, may be important. This study investigated the prevalence and associations of albuminuria and NAP, and the optimum number of urine specimens required.

Methods

1,741 patients with CKD stage 3, recruited from primary care, underwent medical history, clinical assessment, blood sampling, and submitted three early morning urine samples for albumin to creatinine ratio (uACR) and protein to creatinine ratios (uPCR). Albuminuria was defined as uACR ≥3 mg/mmol in at least two of three samples. Isolated NAP was defined as uPCR ≥17 mg/mmol in two of three samples and uACR <3 mg/mmol in all three. Prevalence and associations of albuminuria and NAP, degree of agreement between single uACR and average of three uACRs, and urine albumin to protein ratio (uAPR = uACR/uPCR) were identified.

Results

Albuminuria prevalence was 16% and NAP 6%. Using a <1 mg/mmol threshold for uACR reduced NAP prevalence to 3.6%. Independent associations of albuminuria were: males (OR 3.06 (95% CI, 2.23–4.19)), diabetes (OR 2.14 (1.53–3.00)), lower estimated glomerular filtration rate ((OR 2.06 (1.48–2.85) 30–44 vs 45–59), and high sensitivity CRP ((OR 1.70 (1.25–2.32)). NAP was independently associated with females (OR 6.79 (3.48–13.26)), age (OR 1.62 (1.02–2.56) 80 s vs 70–79) and high sensitivity CRP ((OR 1.74 (1.14–2.66)). Of those with uPCR≥17 mg/mmol, 62% had uAPR<0.4. Sensitivity of single uACR was 95%, specificity 98%, PPV 90%. Bland Altman plot one vs average of three uACRs showed: mean difference 0.0064 mg/mmol (SD 4.69, limits of agreement −9.19 to +9.20, absolute mean difference 0.837).

Conclusions

In CKD stage 3, albuminuria has associations distinct from those of isolated NAP (except for inflammatory markers). Single uACR categorised albuminuria but average of three performed better for quantification.     

68例维吾尔族IgA肾病患者MBL基因多态性与临床病理相关性分析

目的探讨甘露糖结合凝集素（mannose—binding lectin,MBL）基因第54位密码子多态性与维吾尔族IgA肾病患者临床和病理的关系。方法应用PCR—RFLP方法对68例维吾尔族IgAN患者进行MBL多态性检测,并与患者临床和病理特点进行相关性分析。结果①维吾尔族IgAN中表现为蛋白尿的患者突变型等位基因GAC的发生频率显著高于表现为单纯血尿的患者（P〈0．05）;②维吾尔族IgAN中表现为复合性免疫沉积的患者等位基因GAC的发生频率显著高于表现为单纯免疫沉积的患者（P〈0．05）。结论MBL突变型等位基因GAC与维吾尔族IgAN蛋白尿发生和免疫复合沉积相关。     

IgA肾病合并高尿酸血症的临床分析

目的：探讨血清尿酸对IgA肾病临床,病理及预后的影响,为临床治疗和预后评估提供依据。方法：分析我院2011年1月-2012年1月149例经肾穿活检确诊为原发性IgA肾病患者的临床和病理资料。采用t检验和X2检验进行统计学处理。结果：（1）伴高尿酸血症IgA肾病的发病率为30.2%,男性偏多,男女发病率无统计学差异（P〉0.05）。（2）女性高尿酸血症组BUN、Cys-C、Scr水平显著高于尿酸正常组（P〈0.05）,男性两组间无显著差异（P〉0.05）,而血清UA水平无论男女高尿酸血症组均显著高于尿酸正常组（P〈0.05）;尿酸正常组血清BUN、UA、Cys-C、Scr水平男性显著高于女性（P〈0.05）,高尿酸血症组血清UA水平男性显著高于女性（P〈0.05）;血清IgA、C3、IgA/C3比值无论男女,高尿酸血症组与尿酸正常组均无显著差异（P〉0.05）。（3）高尿酸血症组病理改变以Ⅳ-Ⅴ多见（57.8%）,而正常尿酸组则以Ⅰ-Ⅱ为主（46.2%）,血尿酸正常组与高尿酸血症组Lee＇s分级构成比差异具有统计学意义（P〈0.05）。结论：伴有高尿酸血症的IgA肾病患者男性血尿酸水平高于女性,但血尿酸水平升高对女性肾功能影响更大;高尿酸血症对血清IgA,C3水平的变化影响不大;伴高尿酸血症IgA肾病病理改变程度较尿酸正常组更加严重。     

Periodontal Disease Bacteria Specific to Tonsil in IgA Nephropathy Patients Predicts the Remission by the Treatment

Background

Immunoglobulin (Ig)A nephropathy (IgAN) is the most common form of primary glomerulonephritis in the world. Some bacteria were reported to be the candidate of the antigen or the pathogenesis of IgAN, but systematic analysis of bacterial flora in tonsil with IgAN has not been reported. Moreover, these bacteria specific to IgAN might be candidate for the indicator which can predict the remission of IgAN treated by the combination of tonsillectomy and steroid pulse.

Methods and Findings

We made a comprehensive analysis of tonsil flora in 68 IgAN patients and 28 control patients using Denaturing gradient gel electrophoresis methods. We also analyzed the relationship between several bacteria specific to the IgAN and the prognosis of the IgAN. Treponema sp. were identified in 24% IgAN patients, while in 7% control patients (P = 0.062). Haemophilus segnis were detected in 53% IgAN patients, while in 25% control patients (P = 0.012). Campylobacter rectus were identified in 49% IgAN patients, while in 14% control patients (P = 0.002). Multiple Cox proportional-hazards model revealed that Treponema sp. or Campylobactor rectus are significant for the remission of proteinuria (Hazard ratio 2.35, p = 0.019). There was significant difference in remission rates between IgAN patients with Treponema sp. and those without the bacterium (p = 0.046), and in remission rates between IgAN patients with Campylobacter rectus and those without the bacterium (p = 0.037) by Kaplan-Meier analysis. Those bacteria are well known to be related with the periodontal disease. Periodontal bacteria has known to cause immune reaction and many diseases, and also might cause IgA nephropathy.

Conclusion

This insight into IgAN might be useful for diagnosis of the IgAN patients and the decision of treatment of IgAN.     

IgA肾病合并高尿酸血症患者的危险因素分析

摘要 目的：探讨IgA肾病合并高尿酸血症患者的危险因素。方法：回顾性分析2018年1月至2021年1月于我院进行治疗的IgA肾病患者149例的病理资料,根据高尿酸血症发生情况分为高尿酸血症组（n=65）,正常尿酸组（n=84）。比较两组病理特征,收集患者年龄、性别、BMI、性别、高血压、血肌酐、尿素氮、血白蛋白、血胆固醇、甘油三酯、24 h尿蛋白定量、IL-6、IL-1及胱抑素C及CRP等资料,分析高尿酸血症发生的危险因素。结果：两组患者年龄、BMI、CRP差异无统计学意义（P>0.05）;性别、高血压、血肌酐、尿素氮、血白蛋白、血胆固醇、甘油三酯、24 h尿蛋白定量、IL-6、IL-1及胱抑素C与IgA肾病患者发生高尿酸血症相关（P<0.05）;高尿酸组患者球性硬化、节段硬化、新月体形成、小管萎缩、间质炎性浸润及间质纤维化发生率均显著高于正常尿酸组,差异显著（P<0.05）;多因素非条件Logistic分析显示,性别、高血压、血肌酐、尿素氮、血白蛋白、血胆固醇、甘油三酯、24 h尿蛋白定量、IL-6、IL-1及胱抑素C均是IgA肾病患者发生高尿酸血症的独立危险因素（P<0.05）。结论：患者性别、高血压、血肌酐、尿素氮、血白蛋白、血胆固醇、甘油三酯、24 h尿蛋白定量、IL-6、IL-1及胱抑素C均是IgA肾病患者发生高尿酸血症的危险因素,临床上对于具有危险因素的患者引起重视,提高治疗效果。     

PLA2R Antibody Levels and Clinical Outcome in Patients with Membranous Nephropathy and Non-Nephrotic Range Proteinuria under Treatment with Inhibitors of the Renin-Angiotensin System

Patients with primary membranous nephropathy (MN) who experience spontaneous remission of proteinuria generally have an excellent outcome without need of immunosuppressive therapy. It is, however, unclear whether non-nephrotic proteinuria at the time of diagnosis is also associated with good prognosis since a reasonable number of these patients develop nephrotic syndrome despite blockade of the renin-angiotensin system. No clinical or laboratory parameters are available, which allow the assessment of risk for development of nephrotic proteinuria. Phospholipase A₂ Receptor antibodies (PLA₂R-Ab) play a prominent role in the pathogenesis of primary MN and are associated with persistence of nephrotic proteinuria. In this study we analysed whether PLA₂R-Ab levels might predict development of nephrotic syndrome and the clinical outcome in 33 patients with biopsy-proven primary MN and non-nephrotic proteinuria under treatment with blockers of the renin-angiotensin system. PLA₂R-Ab levels, proteinuria and serum creatinine were measured every three months. Nephrotic-range proteinuria developed in 18 (55%) patients. At study start (1.2±1.5 months after renal biopsy and time of diagnosis), 16 (48%) patients were positive for PLA₂R-Ab. A multivariate analysis showed that PLA₂R-Ab levels were associated with an increased risk for development of nephrotic proteinuria (HR = 3.66; 95%CI: 1.39–9.64; p = 0.009). Immunosuppressive therapy was initiated more frequently in PLA₂R-Ab positive patients (13 of 16 patients, 81%) compared to PLA₂R-Ab negative patients (2 of 17 patients, 12%). PLA₂R-Ab levels are associated with higher risk for development of nephrotic-range proteinuria in this cohort of non-nephrotic patients at the time of diagnosis and should be closely monitored in the clinical management.     

Elevated Soluble VEGF Receptor sFlt-1 Correlates with Endothelial Injury in IgA Nephropathy

Background

Endothelial injury, which may present clinically as hypertension, proteinuria and increased von Willebrand Factor (vWF) level, is a common manifestation in IgA nephropathy (IgAN). However, causal factors for endothelial injury in IgAN are not completely understood. An imbalance of vascular endothelial growth factor/Soluble fms-like tyrosine kinase-1 (VEGF/sFlt-1) has been observed in many diseases with endothelial dysfunction, including pre-eclampsia and diabetic retinopathy, but whether it contributes to endothelial injury in IgAN requires further exploration.

Methods

Initially, 96 IgAN patients and 22 healthy volunteers were enrolled as a discovery cohort. VEGF/sFlt-1, sFlt-1 and VEGF levels were compared between patients with IgAN and healthy volunteers to explore the underlying factors that contribute to endothelial injury in IgAN. The identified contributor (sFlt-1) was further confirmed in a replication cohort, which included 109 IgAN patients and 30 healthy volunteers. Correlations of sFlt-1 with hypertension, proteinuria, Oxford-E score and plasma vWF were further evaluated in the combined 205 patients with IgAN.

Results

VEGF/sFlt-1 levels were significantly lower in IgAN patients than healthy volunteers (0.33±0.27 vs. 0.43±0.22, p = 0.02) in the discovery cohort. Within the ratio, plasma sFlt-1 levels were significantly elevated (101.18±25.19 vs. 79.73±18.85 pg/ml, p<0.001), but plasma VEGF levels showed no significant differences. Elevated sFlt-1 levels in the replication cohort were confirmed in IgAN patients (93.40±39.78 vs. 71.92±15.78 pg/ml, p<0.001). Plasma sFlt-1 levels in IgAN patients correlated with proteinuria (severe (>3.5 g/d) vs. moderate (1–3.5 g/d) vs. mild (<1 g/d) proteinuria: 115.95±39.09 vs. 99.89±28.55 vs. 83.24±33.92 pg/ml; severe vs. mild: p<0.001, moderate vs. mild p = 0.001, severe vs. moderate: p = 0.014), hypertension (with vs. without hypertension: 107.87±31.94 vs. 87.32±32.76 pg/ml, p = 0.015) and vWF levels (r = 0.161, p = 0.021).

Conclusions

The present study found elevated sFlt-1 in IgAN patients and further identified its correlation with proteinuria, hypertension and vWF levels. These results suggested that elevated sFlt-1 contributes to endothelial injury in IgAN.     

替米沙坦联合阿托伐他汀治疗糖尿病肾病的疗效分析

目的:探讨替米坦联合阿托伐他汀治疗糖尿病肾病(DN)的疗效及机制.方法:选择糖尿病肾病60例,随机分为治疗组和对照组各30例,对照组单用替米沙坦治疗,治疗组应用替米沙坦联合阿托伐他汀治疗,疗程6个月.治疗前后观察TC、TG、尿微量白蛋白(MALB)、24 h尿蛋白、Scr、BUN、C-反应蛋白、IL-6的值.结果:治疗前,两组TC、TG、尿微量白蛋白(MALB)、24 h尿蛋白、Scr、BUN、C-反应蛋白、IL-6的值比较无明显差异(P>0.05),治疗6月后,与治疗前比较,除TC、TG外,两组患者的尿微量白蛋 白(MALB)、24 h尿蛋白、Scr、BUN、C-反应蛋白、IL-6的值下降(P<0.01),治疗组的TC、TG、尿微量白蛋白(MALB)、24 h尿蛋白、Scr、BUN、C-反应蛋白、IL-6值较对照组低,差异有统计学意义(P<0.01).结论:采用替米沙坦和阿托伐他汀治疗糖尿病肾病具有降血脂、减少尿蛋白、改善肾功能、延缓病情进展的作用.