血红蛋白与IgA肾病患者肾小管萎缩/间质纤维化的关系

目的探讨IgA肾病(IgA nephropathy,IgAN)患者血红蛋白(Hb)水平与肾脏病理牛津分级中肾小管萎缩/间质纤维化(T)的关系。方法回顾性分析2010年1月1日至2015年12月31日在深圳市第二人民医院肾活检确诊为IgAN、同时有完整实验室及影像学资料的患者。将所有患者分为贫血组与非贫血组。采用Logistic回归分析确定Hb与肾小管萎缩/间质纤维化的关系;采用平滑曲线拟合分析Hb与肾小管萎缩/间质纤维化可能的曲线关系;采用受试者工作特征曲线(ROC)分析Hb对肾小管萎缩/间质纤维化的诊断价值。结果本研究共纳入IgAN患者630例,贫血组130例(20.63%),非贫血组500例(79.37%);两组间年龄差异无统计学意义,而性别差异有统计学意义(男性35.38%比53.80%,χ2=10.740,P<0.001)。与非贫血组相比,贫血组的患者肾小管萎缩/间质纤维化的比例和24 h尿蛋白量较高(χ2=62.586,P<0.001;Z=-6.082,P<0.001),估算的肾小球滤过率(eGFR)较低(t=7.126,P<0.001)。Logistic回归分析显示,高Hb水平为肾小管萎缩/间质纤维化发生风险减少的独立保护因素(OR=0.973,95%CI 0.958~0.987,P<0.001)。平滑曲线拟合分析显示Hb与肾小管萎缩/间质纤维化呈线性负相关。ROC曲线提示Hb诊断肾小管萎缩/间质纤维化的最佳临界值为120.5 g/L,即提示Hb>120.5 g/L时,肾小管萎缩/间质纤维化的程度可能降低。结论IgAN合并贫血的患者其肾小管萎缩/间质纤维化发生率较高。Hb>120.5 g/L可能减少肾小管萎缩/间质纤维化发生的风险。     

尿N-乙酰-β-D氨基葡萄糖苷酶在IgA肾病肾小管间质损伤中的评估价值

目的评估尿N-乙酰-β-D氨基葡萄糖苷酶在IgA肾病肾小管间质损伤中的价值。方法回顾性分析2014年2月至2018年6月于本院行肾穿刺活检确诊为IgA肾病的患者82例,分为NAG正常组(NAG<12 U/L,14例)、NAG升高组(NAG>12 U/L,68例);分析两组患者间临床与病理指标的差异,并评估NAG与肾小管间质病变的相关关系。结果NAG正常组的NAG、血肌酐、胱抑素-C、尿微量白蛋白的统计量显著低于NAG升高组(P<0.05),NAG正常组的eGFR的统计量显著高于NAG升高组(P<0.05),病理改变中,NAG正常组的肾小球系膜细胞增殖、肾间质炎症细胞浸润、肾间质纤维化、肾小管萎缩积分显著低于NAG升高组,进一步logistic回归分析显示微量白蛋白、eGFR、系膜增殖、肾小管间质的病理改变为影响NAG水平的独立危险因素。结论尿NAG水平与患者eGFR、mALB以及小管间质病变密切相关,可以作为评估和监测IgAN的小管间质病变程度的临床指标。     

Related factors of hyperuricemia in IgA nephropathy patients

Objective To investigate the influencing factors of hyperuricemia in patients with IgA nephropathy (IgAN). Methods A retrospective study was performed in patients with renal biopsy diagnosed as IgAN in the Department of Nephrology, Provincial Hospital of Anhui Medical University from January 2016 to October 2018. According to the blood uric acid level, they were divided into two groups: patients with hyperuricemia and patients without hyperuricemia. The general clinical indicators and renal pathological data were compared between the two groups. Logistic regression model was used to analyze the influencing factors of hyperuricemia in IgAN patients. Results A total of 125 IgAN patients with age of (35.70±11.16) years old were enrolled, including 63 males and 62 females. The morbidity of hyperuricemia was 44.0%(55/125). Compared with the normal blood uric acid group, the blood urea nitrogen, serum creatinine and the proportion of chronic kidney disease (CKD) stage 3-5, small arterial wall thickening, fibrous crescents/globules, renal interstitial fibrosis, renal tubular atrophy, glomerular sclerosis and inflammatory cell infiltration in the hyperuric acid group were higher, while the level of estimated glomerular filtration rate (eGFR) was lower. And the differences were statistically significant (all P＜0.05). Multivariate logistic regression analysis showed that the level of serum creatinine was an independent related factor of hyperuricemia in IgAN patients (OR=1.034, 95%CI 1.005-1.064, P=0.021). Conclusions IgAN patients with hyperuricemia presented more severe glomerular, tubular and interstitial lesions, and the level of serum creatinine is an independent related factor of hyperuricemia in IgAN patients. High uric acid level may have an important influence on the progression of IgAN, so good control of serum uric acid may improve the prognosis of patients with IgAN.     

The correlation between serum levels of oxidative stress indicators and renal interstitial fibrosis in patients with IgA nephropathy

Objective To investigate the relationship between serum levels of oxidative stress indicators and the degree of renal interstitial fibrosis in patients with IgA nephropathy (IgAN). Methods Seventy eight patients with confirmed primary IgAN in General Hospital of Ningxia Medical University from January 2013 to December 2014 were enrolled. The patients were divided into T0 group (n=30), T1 group (n=26) and T2 group (n=22) according to the grade of tubular atrophy/interstitial fibrosis of Oxford pathological classification criteria for IgAN in 2009. Meanwhile, thirty cases of health examiner were enrolled as control subjects. The levels of serum malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) were detected by xanthine oxidase method, thiobarbituric acid spectrophotometry method, ultraviolet spectrophotometry method, chemical colorimetric method, respectively. The levels of serum advanced oxidation protein products (AOPPs), transforming growth factor beta 1 (TGF-β1), monocyte chemotactic protein 1 (MCP-1), transforming growth factor alpha (TGF-α), interleukin 6 (IL-6) and hypoxia inducible factor 1 alpha (HIF-1α) were detected by enzyme linked immunosorbent assay (ELISA) in all groups. Spearman correlation analysis was used to analyze the correlation between serum oxidative stress indicators and traditional risk factors of tubular atrophy/renal interstitial fibrosis. Multivariable linear regression analysis was used to analyze the correlation between oxidative stress indicators and degree of renal tubular atrophy/renal interstitial fibrosis. Results There were differences in serum levels of AOPPs, MDA, SOD, CAT and GSH-Px in IgAN patients with different degrees of renal interstitial fibrosis (all P﹤0.05). With the increase of renal interstitial fibrosis, the levels of AOPPs and MDA increased gradually, while the levels of SOD, CAT and GSH-Px decreased gradually. Serum AOPPs, MDA, SOD, CAT, GSH-Px concentration in IgAN patients were correlated with the mean arterial pressure (MAP), total blood protein (TP), albumin (Alb), Scr, uric acid (UA), 24-hour urinary protein volume and estimated glomerular filtration rate (eGFR). Multivariate regression analysis showed that the AOPPs levels of blood were positively correlated with MAP, Scr, UA and 24-hour urinary protein (all P﹤0.01), and negatively correlated with TP, Alb, eGFR (all P﹤0.05). The serum levels of AOPPs and MDA in IgAN patients were positively correlated with the levels of TGF-β1, MCP-1, TGF-α, IL-6 and HIF-1α. The levels of SOD, CAT and GSH-Px were negatively correlated with the levels of TGF-β1, MCP-1, TGF-α, IL-6 and HIF-1α. Multivariate stepwise regression analysis showed that the degree of renal interstitial fibrosis in IgAN patients was positively correlated with serum AOPPs level (β=0.285, P=0.001), negatively correlated with CAT (β=-0.346, P﹤0.001), GSH-Px (β=-0.303, P﹤0.001). Conclusions The level of serum oxidative stress in IgAN patients is elevated and positively correlated with the degree of renal interstitial fibrosis, suggesting that oxidative stress may be involved in the occurrence and development of renal interstitial fibrosis.     

Prognostic Value of NGAL Staining in Patients with IgA Nephropathy

Background: Renal tubulointerstitial injury plays an important role in disease progression of IgAN. Neutrophil gelatinase-associated lipocalin (NGAL) is a stress protein released by tubular cells. NGAL is a promising biomarker of acute kidney injury. There is a growing literature suggesting that NGAL is also a marker of chronic kidney disease and severity. Our aim was to evaluate the prognostic value of NGAL staining in patients with IgAN. Methods: This retrospective study included all consecutive patients who underwent a renal biopsy at our center between January 2005 and December 2009. Forty-five patients with IgA nephritis were enrolled, and renal biopsy specimens of 29 patients were evaluated. We evaluated baseline age, sex, hypertension, serum creatinine, glomerular filtration rate (GFR), urine protein, NGAL staining, glomerulosclerosis, interstitial fibrosis, and extracapillary proliferation. The primary endpoint of this study was doubling of baseline serum creatinine and/or the onset of ESRD in the course of the study. At the end of the follow-up, patients whose estimated GFR (eGFR) was ≤15 mL/min/1.73 m² and/or baseline serum creatinine doubled, were defined as the progressor group. Results: Nineteen patients (65.5%) were NGAL positive and 10 patients (34.5%) were NGAL negative. Female gender and hypertension were associated with NGAL-positive staining. Urinary protein excretion and serum creatinine levels were more elevated in the NGAL-positive group, but the difference was not significant. We found NGAL-positive staining in major proportion in the progressor group (88.9%) than the non-progressor group (55%) (p = 0.076). Conclusion: NGAL staining can be a new histological marker in IgAN progression.     

Clinicopathological and prognostic analysis of IgA nephropathy patients with anemia

Objective To analyze the clinicopathological features of IgA nephropathy (IgAN) patients with anemia and the influencing factors of prognosis. Methods The clinical and pathological data of patients diagnosed with primary IgAN at the First Affiliated Hospital of Fujian Medical University from January 1, 2006 to December 31, 2016 were retrospectively analyzed. The patients were divided into anemia group and non-anemia group according to whether the patient was anemia or not. The clinical and pathological data of the two groups were collected. All of them were followed up from the date of renal biopsy to January 1, 2018. Survival curves of the two groups were drawn by Kaplan-Meier method, and compared by Log-rank test. Multivariate Cox proportional hazards regression model was adopted to explore the influencing factors of prognosis in IgAN patients. Results A total of 231 subjects were enrolled, including 122 males (52.8%), and the male-female ratio was 1.12∶1. Their age was (34.8±10.1) years (15-68 years). There were 70 patients (30.3%) in anemia group, 161 cases (69.7%) in non-anemic group. Compared with non-anemia group, anemia group had higher proportion of females, lower serum albumin, higher proportion of tubular atrophy/interstitial fibrosis (T1/2), endothelial cell proliferation (E1) and crescent formation (C1/2), which were statistically significant (all P＜0.05). The patients had a median follow-up time as 6.3 years (0.3-12.9 years). Survival analysis showed that patients in anemia group had lower cumulative renal survival rate than that in non-anemia group ( χ2=15.234, P＜0.001). Multivariate Cox hazards regression analysis revealed that anemia (HR=3.820, 95%CI 1.674-8.719, P=0.001), tubular atrophy/interstitial fibrosis (T1/2) (HR=3.770, 95%CI 1.026-13.852, P=0.046), glomerular segmental sclerosis/adhesion (S1) (HR=4.211, 95%CI 1.139-15.576, P=0.031), hypertension (HR=2.988, 95%CI 1.276-6.999, P=0.012), increased 24 h urinary protein (HR=1.103, 95%CI 1.046-1.163, P＜0.001) and estimated glomerular filtration (eGFR)＜60 ml?min-1?(1.73 m2)-1 (HR=3.725, 95%CI 1.639-8.462, P=0.002) were the independent risk factors for poor renal prognosis in patients with IgAN. Conclusions The clinicopathological features of IgAN patients with anemia are relatively serious, and the renal cumulative survival rate is lower. Anemia, tubular atrophy/interstitial fibrosis (T1/2), glomerular segmental sclerosis/adhesion (S1), hypertension, increased urinary protein and eGFR＜60 ml?min-1?(1.73 m2)-1 are the independent risk factors for poor renal prognosis in patients with IgAN.     

正常血压IgA肾病患者动脉病变的意义

目的:传统观点认为动脉硬化与高血压有关。然而,部分IgA肾病患者,尽管血压正常,但仍有动脉硬化的改变。本研究的目的就是比较血压正常、伴有和不伴有动脉病变的IgA肾病患者的临床病理特点,探讨正常血压IgA肾病患者肾内动脉病变的影响因素及意义。方法:所有患者均经肾活检诊断为原发性IgA肾病,无高血压病史,肾活检前血压<140/90mmHg。动脉病变的定义为活检肾组织光镜下见动脉壁增厚和(或)动脉玻璃样变。符合标准的105例患者,根据动脉病变的有无分为两组,有动脉病变组52例、无动脉病变组53例,分别比较两组的临床病理特点。肾脏动脉病变的半定量分级标准:0:无损害;1:<25%;2:≥25%,<50%;3:≥50%。统计学方法:分别比较两组的临床病理特点,将差异有统计学意义的单因素指标作为多因素分析的入选指标,采用逐步回归方法分析动脉病变的影响因素,以P<0.05作为差异有统计学意义。结果:与无动脉病变组比较,动脉病变组肾活检时的年龄、血肌酐、血尿酸、尿蛋白定量、尿NAG酶、肾小球硬化、肾小管萎缩以及肾间质纤维化的程度显著增高,尿渗透压显著下降。多因素分析的结果表明,肾活检时的血肌酐、尿渗透压、肾小管萎缩及肾间质纤维化是正常血压IgA肾病动脉病变的独立影响因素。动脉病变的程度与血肌酐、肾小管萎缩及肾间质纤维化呈正相关;与尿渗透压呈负相关。结论:血压正常IgA肾病患者的肾内动脉病变,主要与年龄、血肌酐、血尿酸增高等因素有关,常伴有肾小管间质损害。     

Clinical and pathological significance of circadian blood pressure rhythm change in IgA nephropathy patients with hypertension

Objective To investigate whether the clinical and pathological injury of kidney in IgA nephropathy (IgAN) patients with hypertension is associated with circadian blood pressure rhythm change, particularly with elevated nocturnal blood pressure (BP). Methods This study was a retrospective cross-sectional study. Clinic and renal histopathological injury data were obtained from 83 IgAN patients with hypertension. First, 24 h ambulatory BP monitoring (ABPM) data were analyzed. Second, all these IgAN patients were divided into two groups, elevated nocturnal BP group and nocturnal normotensive BP group, and the clinical and pathological differences between this two groups were analyzed. Third, logistic regression analysis was used to analyze the influencing factors of renal tubulointerstitial injury in IgAN patients with hypertension. At last, all these IgAN patients were divided into two groups according to the level of estimated glomerular filtration rate (eGFR), group of patients with eGFR≥60 ml?min-1?(1.73 m2)-1 and the other group with eGFR＜60 ml?min-1?(1.73 m2)-1, and the 24 h ABPM data were compared. Results (1) The proportion of non-dipper circadian rhythm of BP in IgAN patients with hypertension was 79.5%. (2) Compared with nocturnal normotensive BP group, patients in elevated nocturnal BP group had significantly higher levels of 24-hour urinary protein quantity and blood uric acid (both P＜0.05), and lower eGFR and urine osmotic pressure clinically (both P＜0.05). Index of interstitial fibrosis and tubular atrophy was significantly higher in nocturnal normotensive BP group (P＜0.05), while the proportion of glomerular ischemia lesion was not significantly different between two groups. (3) Multivariate logistic regression analysis showed that elevated nocturnal BP was an independent risk factor for severe tubulointerstitial injury of IgAN (OR=1.113, 95%CI 1.038-1.192, P=0.002). (4) Compared with the group of eGFR≥60 ml?min-1?(1.73 m2)-1, 24-hour systolic blood pressure (SBP) and diastolic blood pressure (DBP), daytime SBP and DBP, nocturnal SBP and DBP were significantly higher in group of eGFR＜60 ml?min-1?(1.73 m2)-1 (all P＜0.05). Conclusion The proportion of non-dipper circadian rhythm of BP in IgAN patients with hypertension is as high as 79.5%. Elevated nocturnal BP is associated with the severity of renal damage, and elevated nocturnal BP is an independent risk factor for severe tubulointerstitial injury in IgAN patients with hypertension. Therefore, 24 h ABPM should be emphasized, and elevated nocturnal BP should be well controlled to slow the progression of IgAN.     

尿NGAL在2型糖尿病肾病肾小管间质损伤评价中的价值

目的探讨尿中性粒细胞明胶酶相关载脂蛋白(NGAL)对评价2型糖尿病肾病(DN)患者肾小管间质损伤的价值。 方法研究对象为2012年1月至2015年12月第三军医大学大坪医院2型糖尿病患者167例(2型糖尿病组);将2型糖尿病组再分为正常白蛋白尿组(n＝56)、微量白蛋白尿组(n＝58)、大量白蛋白尿组(n＝53),其中51例患者进行了肾活检。50例非糖尿病患者作为正常对照组。采用酶联免疫吸附测定方法检测尿液中NGAL水平,分光光度法测定尿N-乙酰-β-D-葡萄糖苷酶(NAG)。分析尿NGAL水平与肾功能相关指标[尿NAG、尿白蛋白/肌酐比值(ACR)、eGFR]及肾组织损伤病理评分之间的相关性,以及NGAL对DN肾小管间质损伤严重程度的评价效能,采用SPSS软件进行统计学分析,相关性分析采用Pearson或Spearman方法。 结果糖尿病患者尿NGAL水平较非糖尿病正常对照组明显增加;尿NGAL水平与尿NAG、ACR呈正相关(r＝0.528, 0.578,P<0.001),与eGFR呈负相关(r＝－0.637,P<0.001);尿NGAL水平与DN肾小管萎缩与间质纤维化(IFTA)的严重程度呈显著正相关(r＝0.652,P<0.001);尿NGAL曲线下面积最大(AUC＝0.868),特异度94.7%,敏感度71.9%。 结论尿NGAL是评价DN肾小管间质损伤理想的生物标志物之一。     

Severity of nephrotic IgA nephropathy according to the Oxford classification

Background

IgA nephropathy with nephrotic syndrome (nephrotic IgAN) is a rare form of IgAN. Its prognosis and response to steroid therapy are still controversial because the differential diagnosis between nephrotic IgAN and minimal change nephrotic syndrome with IgA depositions is sometimes confused.

Methods

In this retrospective cohort analysis, we accurately diagnosed 42 cases of nephrotic IgAN (4.4%) from 954 IgAN patients, according to the Oxford classification. We analyzed the clinical and histological data, prognosis, and response to steroid therapy.

Results

In nephrotic IgAN, mean estimated glomerular filtration rate (eGFR) was 51.1?±?24.6?ml/min, proteinuria was 5.71?±?2.56?g/day, and urinary red blood cells were 51.0?±?37.8 high power field. Both active and chronic histological lesions were observed. Cumulative renal survival rate was significantly lower in nephrotic IgAN than in non-nephrotic IgAN (the control group consisted of 47 non-nephrotic IgAN patients diagnosed between 1995 and 1996) (log-rank test: P?Conclusion Nephrotic IgAN is a very severe form of IgAN, with renal dysfunction, massive hematuria, and active and chronic histopathological lesions. Renal outcome is severe; however, steroid therapy can improve prognosis in cases with higher eGFR and lower T-grade, according to the Oxford classification.     

Increased urinary excretion of monocyte chemoattractant protein-1 in proteinuric renal diseases

Monocyte chemoattractant protein-1 (MCP-1) is a chemokine that is produced mainly by tubular epithelial cells in kidney and contributes to renal interstitial inflammation and fibrosis. More recently, we have demonstrated that urinary MCP-1 excretion is increased in proportion to the degree of albuminuria (proteinuria) and positively correlated with urinary N-acetylglucosaminidase (NAG) levels in type 2 diabetic patients. Based on these findings, we have suggested that heavy proteinuria, itself, probably aggravates renal tubular damage and accelerates the disease progression in diabetic nephropathy by increasing the MCP-1 expression in renal tubuli. In the present study, to evaluate whether urinary MCP-1 excretion is increased in the proteinuric states not only in diabetic nephropathy but also in other renal diseases, we examined urinary MCP-1 levels in IgA nephropathy patients with macroalbuminuria (IgAN group; n = 6), and compared the results with the data obtained from type 2 diabetic patients with overt diabetic nephropathy (DN group; n = 23) and those without diabetic nephropathy (non-DN group; n = 27). Urinary MCP-1 excretion levels in non-DN, DN, IgAN groups were 157.2 (52.8-378.5), 346.1 (147.0-1276.7), and 274.4 (162.2-994.5) ng/g creatinine, median (range), respectively. Expectedly, urinary MCP-1 and NAG excretion levels in DN and IgAN groups were significantly elevated as compared with non-DN group. Therefore, we suggest that MCP-1 expression in renal tubuli is enhanced in proteinuric states,irrespective of the types of renal disease, and that increased MCP-1 expression probably contributes to renal tubular damage in proteinuric states.     

The outcome of acute interstitial nephritis: risk factors for the transition from acute to chronic interstitial nephritis

BACKGROUND: Acute interstitial nephritis has been known as a complication of mainly streptococcal infection for nearly a century. With the advent of infection control, it became a complication caused by antibiotics and later by other drugs, which might have changed the outcome. To determine risk factors for the development of chronic renal insufficiency, and thus, the transition from acute to chronic interstitial nephritis, we performed a retrospective study of all cases of acute interstitial nephritis found by reviewing 1,068 renal biopsies from 1968 to 1997. METHODS: Patients with permanent and reversible renal insufficiency after acute interstitial nephritis were compared with respect to the causative event, the symptoms, and the clinical and histological findings. Differences between the groups were calculated by applying bi- and multivariate analysis. RESULTS: Acute interstitial nephritis was found in 6.5% of all biopsies (64 patients with 68 episodes of acute interstitial nephritis); it was infection-induced in 10%, idiopathic in 4%, and drug-induced in 85% of the cases (antibiotics in 13 cases, analgesics in 17, non-steroidal anti-inflammatory drugs (NSAIDs) in 16, diuretics in 5, and various other drugs in 7). Renal insufficiency was reversible in 69% and permanent in 31% (12% partially reversible, 19% irreversible). The infection-induced and idiopathic types of acute interstitial nephritis were always reversible. Drug-related acute interstitial nephritis caused permanent renal insufficiency in 36% with a maximum of 56% in NSAID-induced cases. In drug-induced cases, intake of the suspected drug for more than a month prior to diagnosis caused permanent renal insufficiency in 88% and interstitial granuloma in 31%. Multivariate analysis disclosed the following significant features separating the permanent from the reversible renal insufficiency group: patients in the first group had more tubular atrophy in their histology, more chronic use of mixed analgesics and/or NSAIDs, less oliguria or anuria as an acute symptom, fewer antibiotics as causative agents, more interstitial granuloma, more pronounced interstitial cell infiltration in their histology, and more imaging of renal shrinkage. Renal histology had the highest predictive value. CONCLUSION: Today, acute interstitial nephritis is mainly drug-induced. NSAIDs are the most frequent cause of permanent renal insufficiency after acute interstitial nephritis. Clinically, subacute symptoms, a prolonged intake of the suspect drug, and chronic analgesic or NSAID use are related to a more chronic course of interstitial nephritis. In histology, tubular atrophy, interstitial granuloma, and pronounced interstitial cell infiltration indicate chronicity.     

Detection of subclinical tubular injury after renal transplantation: comparison of urine protein analysis with allograft histopathology

BACKGROUND: Tubulointerstitial injury due to rejection leads to tubular atrophy (TA)/interstitial fibrosis (IF) followed by deterioration of allograft function. This study investigated whether urinary tubular injury biomarkers can detect subclinical tubulitis found in protocol biopsies allowing for a noninvasive screening procedure. METHODS: Four rigidly defined groups (stable transplants with normal tubular histology [n=24], stable transplants with subclinical tubulitis [n=38], patients with clinical tubulitis Ia/Ib [n=18], and patients with other clinical tubular pathologies [n=20]) were compared for differences in urinary intact/cleaved beta2-microglobulin (i/cbeta2m), retinol-binding protein (RBP), neutrophil-gelatinase-associated lipocalin (NGAL), and alpha1-microglobulin (alpha1m). RESULTS: Tubular proteinuria was present in 38% (RBP) to 79% (alpha1m) of patients in the stable transplant with normal tubular histology group. The stable transplant with subclinical tubulitis group had slightly higher levels of i/cbeta2m (P=0.11), RBP (P=0.17), alpha1m (P=0.09), and NGAL (P=0.06) than the stable transplant with normal tubular histology group with a substantial overlap. The clinical tubulitis Ia/Ib and the other clinical tubular pathology groups had significantly higher levels of RBP, NGAL, and alpha1m than stable transplants with normal tubular histology or stable transplants with subclinical tubulitis (P<0.002). CONCLUSIONS: None of the investigated biomarkers allow for clear differentiation between stable transplants with normal tubular histology and stable transplants with subclinical tubulitis. Therefore, the protocol allograft biopsy currently remains the preferred tool to screen for subclinical tubulitis. Further longitudinal studies should determine whether tubular proteinuria in stable transplants with normal tubular histology indicates a clear risk for early development of TA/IF.     

成人微小病变肾病综合征发生急性肾损伤的相关影响因素分析

目的探讨成人微小病变肾病综合征发生急性肾损伤( AKI)的相关影响因素。 方法回顾性分析2002年1月1日至2015年12月31日在解放军总医院病理诊断为微小病变肾病,临床表现为首发肾病综合征的成年患者。记录其横断面临床及病理指标,并将其分为AKI组及非AKI组进行比较。用单因素及多元Logistic回归分析与AKI发生相关的影响因素。并对AKI相关的各影响因素进行交互作用检验。 结果共纳入403例患者,男女比例为1∶1.13,肾活检时平均年龄为(39.5 ± 15.1)岁,其中118(29.3%)例发生了AKI。AKI组与非AKI组相比,年龄、性别、尿蛋白定量、血清白蛋白、血肌酐、血尿素氮、估算的肾小球率过滤、肾小管萎缩、肾间质病变差异均有统计学意义(P<0.05)。单因素Logistic回归分析显示高龄、男性、尿蛋白定量多、肾小管萎缩、肾间质水肿、间质纤维化及炎细胞浸润、高血压是成人微小病变肾病发生AKI的危险因素。交互作用检验表明血清白蛋白对AKI的作用受到肾间质纤维化的显著影响(P＝0.0 050),且在调整年龄分组、性别、高血压、尿蛋白定量、肾小管萎缩、肾间质水肿、肾间质炎细胞浸润混杂因素后,其交互作用仍显著(P＝0.0 263)。从多元Logistic回归分析可见,在无肾间质纤维化的人群中,血清白蛋白水平的升高是AKI的独立保护因素(调整后的OR 0.8,95%CI 0.7～ 0.9,P<0.001)。在有肾间质纤维化人群中,血清白蛋白的升高对AKI肾脏的保护作用不显著(调整后的OR 1.0,95%CI 0.9～1.0,P＝0.0 278)。 结论高龄、男性、尿蛋白定量多、肾小管萎缩、肾间质水肿、间质纤维化及炎细胞浸润、高血压是成人微小病变肾病综合征发生AKI的危险因素。血清白蛋白升高对AKI的保护作用受到肾间质纤维化的影响。     

Increased Urinary Excretion of Monocyte Chemoattractant Protein-1 in Proteinuric Renal Diseases

Monocyte chemoattractant protein-1 (MCP-1) is a chemokine that is produced mainly by tubular epithelial cells in kidney and contributes to renal interstitial inflammation and fibrosis. More recently, we have demonstrated that urinary MCP-1 excretion is increased in proportion to the degree of albuminuria (proteinuria) and positively correlated with urinary N-acetylglucosaminidase (NAG) levels in type 2 diabetic patients. Based on these findings, we have suggested that heavy proteinuria, itself, probably aggravates renal tubular damage and accelerates the disease progression in diabetic nephropathy by increasing the MCP-1 expression in renal tubuli. In the present study, to evaluate whether urinary MCP-1 excretion is increased in the proteinuric states not only in diabetic nephropathy but also in other renal diseases, we examined urinary MCP-1 levels in IgA nephropathy patients with macroalbuminuria (IgAN group; n = 6), and compared the results with the data obtained from type 2 diabetic patients with overt diabetic nephropathy (DN group; n = 23) and those without diabetic nephropathy (non-DN group; n = 27). Urinary MCP-1 excretion levels in non-DN, DN, IgAN groups were 157.2 (52.8–378.5), 346.1 (147.0–1276.7), and 274.4 (162.2–994.5) ng/g creatinine, median (range), respectively. Expectedly, urinary MCP-1 and NAG excretion levels in DN and IgAN groups were significantly elevated as compared with non-DN group. Therefore, we suggest that MCP-1 expression in renal tubuli is enhanced in proteinuric states, irrespective of the types of renal disease, and that increased MCP-1 expression probably contributes to renal tubular damage in proteinuric states.     

Urinary levels of macrophage migration inhibitory factor in patients with IgA nephropathy

BACKGROUND/AIM: The processes involved in development of IgA nephropathy (IgAN) are not yet well understood. Macrophage migration inhibitory factor (MIF) is a potent pro-inflammatory cytokine and is an essential component of immune and inflammatory responses. To examine further the possible role of MIF in IgAN, we measured MIF levels in the urine. The purpose of the present study was to evaluate the involvement of MIF in IgAN. METHODS: Urine samples were obtained from 20 IgAN patients. The disease controls included 20 patients with minimal-change nephrotic syndrome (MCNS). A group of healthy subjects served as control. The samples were assayed for MIF protein by a sandwich enzyme-linked immunosorbent assay (ELISA). RESULTS: The MIF levels in the urine of patients with IgAN examined were significantly higher than those of the healthy control subjects. In contrast, the levels of urinary MIF (uMIF) in patients with MCNS did not differ significantly from normal values. In IgAN patients, uMIF significantly correlated with the magnitude of proteinuria, but not with the grade of hematuria. We also investigated the relationship between uMIF levels and pathological features. Among patients with IgAN, uMIF levels were significantly correlated with the grade of glomerular crescent formation and that of mesangial cell proliferation. There was also a significant correlation between uMIF levels and the number of both intraglomerular and interstitial macrophages. CONCLUSION: Although the underlying mechanisms remain to be determined, these data provide evidence that urinary excretion of MIF is increased in IgAN patients with active renal lesions.     

原发性肾病综合征患者中性粒细胞明胶酶相关脂质运载蛋白的变化及意义

目的 探讨原发性肾病综合征(PNS)患者中性粒细胞明胶酶相关脂质运载蛋白(NGAL)的变化以及与病理类型、肾小管间质损伤程度、临床指标的关系. 方法 40例PNS患者按有无急性肾小管坏死(ATN)分急性肾损伤(AKI)组及非AKI组,按病理类型分微小病变型肾病(MCD)组、系膜增生性肾小球肾炎(MsPGN)组、局灶性节段性肾小球硬化(FSGS)组、膜增生性肾小球肾炎(MPGN)组、膜性肾病(MN)组;20例健康体检者及20例因肾肿瘤做肾切除术但远离肿瘤部位的正常肾组织作正常对照.采用酶联免疫吸附试验(ELISA)法检测血清、尿液NGAL水平,免疫组织化学染色法观察肾组织NGAL表达.结果 (1) AKI组患者血、尿NGAL水平及肾组织NGAL表达显著高于非AKI组及对照组(P＜0.05).(2)MPGN组及FSGS组患者血、尿NGAL水平及肾组织NGAL表达显著高于其他病理类型组(P＜0.05).(3)在肾小管间质发展至重度病变之前,随着肾小管间质损伤程度的加重,血、尿NGAL水平及肾组织NGAL表达逐渐升高;在肾小管间质发展至重度病变时,血NGAL水平及肾组织NGAL表达下降(P＜0.05).(4)血、尿NGAL水平及肾组织NGAL表达与血肌酐呈正相关(r值分别为0.198、0.352、0.146,P值分别为0.048、0.000、0.028),与尿素氮呈正相关(r值分别为0.199、0.278、0.325,P值分别为0.043、0.000、0.019),与血白蛋白呈负相关(r值分别为-0.384、-0.318、-0.259,P值分别为0.028、0.024、0.020),与尿渗透浓度呈负相关(r值分别为-0.250、-0.256、-0.277,P值分别为0.012、0.027、0.002).结论 NGAL可作为预测PNS患者AKI的敏感指标,在一定程度下可用于评价肾小管间质病变程度及肾功能.     

Association between obesity and absolute renal risk factors in patients with IgA nephropathy

Objective To investigate the influence of obesity on renal lesion in IgA nephropathy (IgAN) patients by analyzing the association between obesity and absolute renal risk factors (ARR). Method Clinical-pathological data of IgAN patients diagnosed by renal biopsy in General Hospital of Ningxia Medical University were collected retrospectively. According to the body mass index (BMI), patients were divided into non-obese group (BMI＜28, N-OB group) and obese group (BMI≥28, OB group). Their clinical characteristics, pathological index and ARR scores were compared. The relationship of BMI and ARR was analyzed by ordinal logistic regression models. Results (1) A total of 674 IgAN patients with mean age of 35.5±11.3 years were enrolled, including 94 in OB group and 580 in N-OB group respectively. Compared with those in the N-OB group, the proportion of male, age, mean arterial pressure, blood uric acid, blood triglyceride, diabetes mellitus and hypertension increased in OB group (all P＜0.01). Patients in OB group had lower estimated glomerular filtration rate (eGFR) and higher ARR score than those in N-OB group (all P＜0.05). (2) More severe thickening renal small artery wall and hyaline degeneration were observed in the OB group than in the N-OB group (all P＜0.01). There was no statistical difference between the two groups in Lee classification, Oxford classification, mesangial cell proliferation, glomerular sclerosis, crescent formation, renal tubular atrophy, interstitial inflammatory cell in filtration and endothelial cell proliferation. (3) After adjusting for age, sex, blood uric acid, serum albumin, eGFR, low density lipoprotein, glomerular sclerosis, interstitial inflammatory cell infiltration, renal tubular atrophy and vascular wall thickening, BMI was still an independent risk factors for ARR in IgAN patients (OR=1.09, 95%CI 1.03-1.14). Conclusions BMI is an independent risk factors for ARR in IgAN patients. Early prevention and control of obesity and its associated risk factors may improve outcomes of IgAN patients.     

Naproxen-induced nephropathy in systemic lupus erythematosus

A 34-year-old female with an 8-month history of systemic lupus erythematosus and intermittent naproxen use presented with acute oliguric renal failure, hypoalbuminemia, 4+ proteinuria, and an active urinary sediment. The clinical picture suggested a rapidly progressive lupus glomerulonephritis. Renal biopsy, however, demonstrated chronic, active interstitial nephritis without evidence of immune deposits by immunofluorescence or electron microscopy. Nonsclerotic glomeruli revealed diffuse foot process fusion without cellular proliferation. These findings were consistent with nonsteroidal anti-inflammatory drug induced nephropathy. Discontinuation of naproxen and institution of corticosteroid therapy was followed by improvement in renal function and remission of nephrotic syndrome. This case represents the first report of nonsteroidal antiinflammatory drug nephropathy associated with systemic lupus erythematosus.     

Analysis of the clinical pathological characteristics and prognosis of primary IgA nephropathy with hypertension

Objective To investigate the clinic-pathological features and prognostic risk factors of IgA nephropathy (IgAN) with hypertension (HTN). Methods Primary IgAN patients diagnosed with biopsy from January 2016 to December 2017 were recruited. Patients were divided into IgAN with normal blood pressure (IgAN-NTN) group and IgAN with hypertension (IgAN-HTN) group based on the pressure value when performing the kidney biopsy. The clinical and pathological data were collected and compared between the two groups. Kaplan-Meier method was conducted for renal results, whereas the Cox regression model was exploited to analyze the prognostic factors in the progression of IgAN-HTN patients. Results The total number of enrolled patients was 275 cases, 170 (61.82%) of which had normal pressure and 105 individuals (38.18%) resulted in hypertension. The IgAN-HTN group in terms of male proportion, age, systolic pressure, diastolic pressure, serum urea nitrogen, serum creatinine, serum uric acid, 24 h urinary protein, triacylglycerol, complement C4 and so on were higher than those in the IgAN-NTN group (all P＜0.05). The incidence of gross hematuria and the level of estimated glomerular filtration rate (eGFR) were significantly lower than those in the NTN group (all P＜0.001). For the aspect of light microscope pathological manifestations, IgAN-HTN group exhibited more severe histological lesions including glomerular sclerosis, renal tubular atrophy or renal interstitial fibrosis, interstitial vascular injury than IgAN-NTN group (all P＜0.05). Immunofluorescence examination results showed that the deposition ratio of C1q in IgAN-HTN group was higher than that in IgAN-NTN group (P=0.015). By employing Kaplan-Meier method, the cumulative renal survival rate in the HTN group was much lower than that in the NTN group (Log-rank test: χ2=6.456, P=0.011). For the patients in IgAN-HTN group, the cumulative renal survival rate in the dyslipidemia group was much lower than that in the ortholiposis group (Log-rank test: χ2=5.093, P=0.024). There was no significant difference in the cumulative renal survival rate between the blood pressure control group and the unqualified group (Log-rank test: χ2=1.036, P=0.309). As a result of univariate and multivariable Cox regression analysis, total cholesterol, eGFR and 24 h urinary protein were risk factors for renal progression of IgAN patients with hypertension. Conclusions The clinical manifestations and renal pathological changes in patients with IgAN-HTN are more serious than those in IgAN-NTN patients, which result in worse prognosis. IgAN-HTN patients should be paid more attention to the management of serum lipid level during treatment and follow-up.