IgA肾病合并高尿酸血症患者的临床病理分析

目的探讨IgA肾病合并高尿酸血症患者的临床及病理变化的特点,以期揭示IgA肾病伴有高尿酸血症的临床意义。方法回顾性分析2006年6月至2012年12月厦门大学附属中山医院肾内科收治的270例经肾活检确诊的原发性IgA肾病患者,依据血尿酸水平,将270例IgA肾病患者分为高尿酸血症组和尿酸正常组,测定记录所有患者的性别、发病年龄、收缩期血压、24 h尿蛋白定量、血尿酸、血肌酐、血白蛋白、血脂等临床指标,所有患者均进行肾脏病理检查并行Lee分级,统计分析2组的临床和病理特点,并对肾功能正常患者(135例)的病理指标进一步行亚组分析。结果IgA肾病患者高尿酸血症的患病率为25.19%,高尿酸血症组患者年龄、血白蛋白、血三酰甘油、血清总胆固醇水平与尿酸正常组比较,差异无统计学意义,患者男性比例、收缩期血压、24 h尿蛋白定量、血肌酐水平均高于尿酸正常组(P0.05),高尿酸血症组患者肾脏病理Lee分级严重的比例及发生肾小管间质病变、肾内动脉病变的比例均高于尿酸正常组(P0.05)。正常肾功能患者中,高尿酸血症组出现动脉壁肥厚等肾内动脉病变及肾小管间质慢性病变的比例亦高于尿酸正常组(P0.05)。结论 IgA肾病合并高尿酸血症患者与尿酸正常组患者比较,临床表现及肾脏病理损伤多较重,尤其对肾小管间质病变及肾内血管病变影响更明显,临床预后不佳,应予重视并及时有效地进行干预治疗。     

IgA serology in recurrent and non-recurrent IgA nephropathy after renal transplantation

BACKGROUND: This study investigated whether abnormal circulation of macromolecularIgA and IgA with altered glycosylation or electrical chargeplays a role in the recurrence of IgA nephropathy (IgAN) aftertransplantation. STUDY DESIGN: A total of 92 renal transplant patients were enrolled; 52 IgANpatients and 40 with other non-IgAN. The IgAN group included10 patients showing IgA mesangial deposits in the grafted kidneys(recurrent group) and 10 who did not (immunohistochemicallyproven non-recurrent group). In addition another 22 IgAN transplantpatients were clinically free of recurrent disease. METHODS: The analyses included macromolecular IgA (IgAIC) detected bythe conglutinin assay (K), heavy IgA precipitated in 2.5% polyethyleneglycol (PEG), IgA-fibronectin aggregates (IgA/F Aggr), mixedIgA/IgGIC, IgA binding to mesangial matrix components (fibronectin,laminin, type IV collagen) or polycations (poly-L-lysine) andIgA with altered glycosylation (Jacalin-binding assay). RESULTS: After transplantation, IgAN patients displayed significantlyhigher mean levels for each variable measured than non-IgAN(ANOVA, P <0.05). By stepwise regression analysis, the bindingof IgA to fibronectin had the highest coefficient. By comparingdata in recurrent and clinically non-recurrent IgAN, we observedthat two groups could be distinguished by the results of thetwo assays for macromolecular IgA (conglutinin IgAIC and IgA-fibronectinaggregates) and IgA with increased affinity for type IV collagen(P <0.05). When the selected group of immunohistochemicallyproven non-recurrent IgAN was compared to the recurrent one,a statistically significant difference was found only for thebinding of IgA to type IV collagen (P<0.05). Data from thistest were significantly related with proteinuria (P<0.05)and microscopic haematuria (P <0.04). CONCLUSION: Even though the IgA serology of renal transplant IgAN patientsshows peculiar features and recurrent and non-recurrent IgANdiffer in many aspects, the prevalence of positive data in thetwo groups had no predictive value. This suggests that the recurrenceof IgAN is modulated by factors affecting the interaction betweencirculating abnormal IgA and mesangial cells and/or matrix.     

Serological and genetic factors in early recurrence of IgA nephropathy after renal transplantation

BACKGROUND: The relative role of IgA anomalies and genetic factors in IgA nephropathy (IgAN) recurrence after transplantation has never been investigated in a single cohort. METHODS: Sixty-one transplanted patients who had IgAN as an original disease (30 with biopsy-proved early recurrence, median 2.9 yr post-transplant), and 120 controls, were investigated for aberrantly glycosylated IgA1, IgA binding to mesangial matrix, macromolecular IgA (IgA/fibronectin and uteroglobulin/IgA/fibronectin complexes), and polymorphisms of cytokines [tumor necrosis factor alpha (TNFalpha), interleukin 10 (IL-10), IL-6, interferon gamma and transforming growth factor beta 1] and renin-angiotensin system (angiotensinogen converting enzyme, angiotensin II receptor 1, and angiotensinogen) genes. RESULTS: At multivariate logistic regression analysis, recurrence showed a border-line association with aberrantly glycosylated IgA1 [odds ratio (OR) 8.172, p = 0.077], and was significantly less frequent in carriers of -308 AG/AA TNF-alpha"high producer" genotype (OR 0.125, p = 0.036) and -1082, -819, -592 ACC/ATA IL-10 "low producer" (OR 0.038, p = 0.009) genotypes. CONCLUSION: High levels of aberrantly glycosylated IgA1 do not appear to play a strong crucial role in recurrence of IgAN. Polymorphisms of TNFalpha and IL-10 known to condition Th1 prevalence were associated with protection from early recurrence of IgAN.     

In situ hybridization studies of stromelysin and tissue inhibitor of metalloproteinase 1 in IgA nephropathy

Summary: Accumulation of the extracellular matrix (ECM) in IgA nephropathy (IgAN) is thought to cause deterioration of glomerular function. Stromelysin and tissue inhibitor of matrix proteinase 1 (TIMP1) may play an important role in the turnover of the glomerular ECM. However, the expression of these enzymes in human renal tissues remains undefined. In the present study, non-radioactive in situ mRNA hybridization, which permitted the analysis at a cellular level, was performed to localize stromelysin and TIMP1 in renal tissue of IgAN. We also determined the percentage of cells positive for stromelysin or TIMP1 mRNA among intraglomerular cells. A total of 16 patients with IgAN were examined, including eight patients with severe histopathological changes and eight with mild changes. Three patients without glomerular disease were also studied. Stromelysin and TIMP1 mRNA were weakly expressed in the mesangium of normal kidneys and IgAN renal tissues with mild damage. However, the expression of both mRNA was significantly increased in the area of mesangial proliferation, in glomerular epithelial cells and in Bowman's capsule of advanced lesions. Several cells in the area of mesangial proliferation were double positive for stromelysin and TIMP1 mRNA, while certain cells positive for stromelysin mRNA did not express TIMP1 mRNA. In the interstitium, epithelial cells of certain tubules and some mononuclear cells were positively stained for these mRNA, especially in advanced lesions. Our results indicated that stromelysin and TIMP1 genes were expressed in glomerular resident cells, tubular epithelial cells and infiltrated mononuclear cells in IgAN, and their expression was enhanced in advanced tissue damage. the demonstration of a co-expression and discordant expression of the genes indicates that each gene expression may be regulated in a cell type-specific manner and that it could also be altered by cellular environmental factors.     

Intrarenal synthesis of IL-6 in IgA nephropathy

Summary: Recent in vitro studies have shown the synthesis of interleukin-6 (IL-6) in glomerular mesangial and epithelial cells, and suggested the involvement of IL-6 in mesangial proliferative glomerulonephritis. However, the expression site of IL-6 mRNA in renal tissue of IgA nephropathy (IgAN), the most common chronic mesangial proliferative glomerulonephritis, remains obscure. to localize IL-6 mRNA in renal biopsy specimens of IgAN, we used nonradioactive in situ hybridization (ISH) developed in our laboratory, sensitive in detecting individual cells positive for a specific mRNA. In some sections, periodic acid-Schiff staining was performed after ISH in order to identify the topographical relation between IL-6 mRNA positive cells and glomerular basement membrane and mesangial area. In situ hybridization for IL-6 mRNA and immunohistochemistry for CD3 and CD68, markers for lymphocytes and monocytes, respectively, were also performed on serial sections to examine the contribution of infiltrated mononuclear cells to cells positive for IL-6 mRNA in glomeruli. Glomerular resident cells, including glomerular mesangial and epithelial cells and cells of Bowman's capsule, as well as tubular epithelial cells and infiltrated mononuclear cells expressed IL-6 mRNA. We also compared the localization of IL-6 mRNA and protein and showed different distribution between the gene product and protein. the expression of IL-6 mRNA correlated with the degree of mesangial cell proliferation and tubulointerstitial changes. Our results indicate that IL-6 is synthesized in renal tissues of IgAN and suggest that the increased IL-6 expression may be important in the pathogenesis of IgAN.     

Recurrence of IgA nephropathy in renal transplants

SUMMARY: The present article provides an update from the literature on the clinical significance of recurrent IgA disease in renal transplant patients, and it identifies possible reasons for the differences between the data that have been published. the clinical features of recurrent IgA nephropathy are described here, along with suggestions for the management of these patients.     

Peritubular capillary C4d deposition and renal outcome in post-transplant IgA nephropathy

BACKGROUNDS: Immunological staining of the transplanted kidney for C4d in peritubular capillaries (C4d(PTC)) has emerged as a useful method to detect antibody-mediated rejection in situ. In this retrospective study, we evaluated the prevalence of C4d(PTC) deposition in allograft renal biopsies diagnosed of IgA nephropathy (IgAN) and analysed its clinical significance. METHOD: Sixty-six biopsy specimens of post-transplant IgAN, which were obtained to evaluate azotemia and/or heavy proteinuria, were examined by immunohistochemical staining of the paraffin sections with polyclonal antibody for C4d. RESULTS: C4d was stained positively in peritubular capillaries in 16 (24%) of the 66 cases. The C4d(PTC)-negative (n=50) and C4d(PTC)-positive groups (n=16) were not different in recipient gender, age, donor age, type of donor (living vs. cadaveric), interval from transplantation to graft biopsy (41.6+/- 21.8 vs. 48.3+/-26.1 months) and post-biopsy follow-up period (60.3+/-23.3 vs. 56.9+/-25.4 months). During the follow-up period, 12 of 50 (24%) although the incidence of graft failure was not different by the C4d deposition in peritubular capillaries, intervals from renal biopsy to graft failure tended to be shorter in C4d(PTC)-positive cases than C4d(PTC)-negative cases. In Kaplan-Meier analysis, the renal allograft function of the C4d(PTC)-positive group deteriorated more rapidly than that of the C4d(PTC)-negative group (p<0.05). Histologically, the C4d(PTC)-positive group had findings suggestive of acute cellular rejection more commonly than the C4d(PTC)-negative group (p<0.01). CONCLUSIONS: Evidence of humoral rejection, as demonstrated by C4d(PTC) deposition, was concurrently present in significant portions of post-transplant IgAN biopsy specimens and was associated with more rapid deterioration of renal function. These results suggest that C4d(PTC) positivity needs to be determined at the time of biopsy even in cases of post-transplant glomerulonephritis and immunosuppression may need to be modified accordingly.     

Clinical risk factors for recurrence of IgA nephropathy

No clinical risk factors for recurrence of immunoglobulin A (IgA) nephropathy in kidney transplants have been defined. This is a single-centre retrospect analysis of recurrence in 104 first kidney transplant patients with biopsy-verified IgA nephropathy. Fifty patients had living donors. All but an identical twin were treated with cyclosporin A. The median follow-up time was 5 yr. Graft biopsies had been obtained from 35 grafts later than 6 months after transplantation, due to deteriorating graft function or gross proteinuria. Thirteen biopsies showed mesangial glomerulopathy proliferative in eleven cases with IgA deposits. Recurrence caused failure of six grafts. Eleven grafts with recurrence were from living donors (p = 0.005). No specific human leukocyte antigen (HLA) was identified as a risk factor. Known duration of original disease until end-stage renal failure was significantly shorter in patients with recurrence (median 5 yr, range 0-25 yr) compared with those without (median of 10 yr, range of 0-37 yr) (p = 0.015). Cumulative graft survival was not reduced in living versus cadaveric donor recipients.     

IgA肾病520例临床病理分析

目的研究IgA肾病(IgAN)的临床和病理特点及其相互关系。方法对1992年11月～2003年6月温州医学院附属第一医院肾内科病理室肾活检诊断的原发性IgAN520例进行临床与病理分型关系的分析。结果520例IgAN临床表现以无症状性尿检异常最常见,占346例(66.5%),其次是慢性肾炎和肾病综合征,分别占77例(14.8%)和66例(12.7%)。病理类型以局灶节段硬化性肾小球肾炎最常见,占186例(35.8%),其次是系膜增生性肾小球肾炎、轻微病变肾小球肾炎和局灶节段增生性肾小球肾炎,分别为116例(22.3%)、104例(20%)和63例(12.1%)。结论IgAN的临床病理表现多样化并具有一定特点。临床表现最常见为无症状性尿检异常,在病理上最常见的是局灶性肾小球病变类型。     

Recurrent IgA nephropathy after renal transplantation despite immunosuppressive regimens with mycophenolate mofetil.

BACKGROUND: Transplantation offers an excellent option for patients with immunoglobulin-A nephropathy (IgAN) with severe renal dysfunction. However, IgAN frequently recurs in allografts treated with azathioprine. We examined the impact of mycophenolate mofetil immunosuppression on recurrence of IgAN. METHODS: We reviewed the charts of patients transplanted for IgAN at our institution in the cyclosporin era. Patients were excluded from further analysis if follow-up was <12 months or if immunosuppression at engraftment did not include azathioprine or mycophenolate mofetil. Laboratory data, medications and allograft biopsy findings were compiled. RESULTS: 152 kidney transplantations met the study criteria. At engraftment, 61 allografts were treated with azathioprine and 91 with mycophenolate mofetil. By 3 years post-transplant, IgAN developed in six of 60 (10.0%) azathioprine-treated allografts and five of 62 (8.1%) mycophenolate mofetil-treated allografts (P = 0.76). Overall, 13 azathioprine-treated and seven mycophenolate mofetil-treated allografts showed recurrence. As expected in this retrospective study, the duration of observation was longer in the azathioprine group. The interval between engraftment and diagnosis of recurrent disease was also longer. Survival of allografts with recurrent IgAN was similar in the two groups. Survival of allografts with recurrent IgAN was worse than for allografts without recurrence or allografts transplanted into patients with non-IgAN renal failure. Neither switching azathioprine to mycophenolate mofetil nor using an angiotensin-converting enzyme inhibitor or angiotensin-II type 1 receptor blocker ameliorated the clinical course after a biopsy documented recurrent IgAN. CONCLUSIONS: Mycophenolate mofetil, compared with azathioprine, did not lessen the recurrence of IgAN or its clinical impact.     

Clinical and pathological analysis of IgA nephropathy with chronic renal failure

Objective: To investigative clinical and pathological characteristics of IgA nephropathy with chronic renal failure.

Method: Clinical and pathological findings from 65 cases of IgA nephropathy with chronic renal failure were reviewed. Pathological characteristics of all the cases were analyzed according to WHO definition and Oxford Classification. Evaluating the severity of pathological lesions by the Katafuchi R semiquantitative scoring system, and analyzing their relationship with clinical indexes of renal function.

Results: Of all 65 cases the male and female ratio was 1.4, and the mean age was 37?±?13 years old. Levels of systolic pressure, mean arterial pressure (MAP), blood urea nitrogen (BUN), serum creatinine (Scr), uric acid (UA), album (Alb), serum IgG and 24?h urinary protein were related with eGRF level (p < 0.05, respectively). The most common pathological type was proliferative sclerosis glomerulonephritis (PSGN) and M1S1E0T0 according to WHO definition and Oxford Classification, respectively, and most of the 65 cases had glomerulosclerosis. Simple IgA deposition was the most common immunopathologic type. Of all the cases, 44.6% accompanied with C3 while 4.6% with C1q. Further analysis revealed there were no relationships between severity of pathological lesion and levels of clinical indexes (Scr and eGRF) (p?>?0.05).

Conclusion: IgA nephropathy with chronic renal failure usually occurred in young adults, and it had severe clinical condition and pathological changes, while there was no significant relationship between them.     

IgA肾病患者肾脏组织中差异细胞因子的探索研究

目的筛选IgA肾病(IgAN)患者肾脏组织中的差异蛋白质-细胞因子,进一步探讨IgAN的发病机制。 方法入选年龄18～60岁,解放军总医院肾脏病科住院肾活检确诊为IgAN患者10例;泌尿外科行肾癌肾脏切除的患者10例,取癌旁6 cm以外正常肾脏组织作为对照。肾脏组织利用L-493细胞因子抗体芯片进行检测,筛选差异蛋白质,并对差异蛋白质进行基因本体论(GO)分析。以IL-33(白介素-33)利用酶联免疫吸附试验(ELISA)进行验证。采用IBM SPSS Statistics 19.0软件对结果进行统计分析,利用T检验对差异蛋白质进行筛选,P<0.05,并且差异蛋白质差异倍数>1.4认为是差异蛋白质。 结果L-493细胞因子抗体芯片检测,在20例患者中(IgAN组10例,对照组10例),发现了25种差异蛋白质,GO分析结果表明：这些蛋白质主要与应激、细胞粘附、蛋白质代谢、信号转导相关。ELISA验证结果显示：IgAN患者肾组织中IL-33表达水平显著高于对照组。 结论IgAN患者肾脏组织中差异表达蛋白质直接或间接调控着炎症、细胞增殖和凋亡及纤维化过程。IL-33可能与IgAN发病机制有关。     

Positive and negative hepatitis B virus in renal biopsies of IgA nephropathy: an 85-case clinicopathological analysis

SUMMARY: The aetiological role of hepatitis B virus (HBV) antigens in IgA nephropathy remains uncertain. In a clinicopathological study, we examined 85 patients with primary IgA nephropathy divided into two groups depending on whether renal biopsy specimens were positive or negative for HBV antigens (HBsAg, HBcAg and HBeAg) using immunohistochemical methods. Compared with patients in the negative group ( n = 59), those in the positive group ( n = 26) had more obvious gross haematuria, proteinuria, hypertension and renal impairment. Their haemoglobin level, serum IgA concentration and creatinine clearance were also significantly abnormal. Immunofluorescence microscopy indicated that immunoglobulins deposited were mainly found in the combination of IgA + IgG + IgM. Consistent with the clinical manifestations, the pathological lesions revealed more glomerular sclerosis, tubular epithelial degeneration and necrosis and interstitial inflammation and fibrosis ( P < 0.05). Thus, we concluded that the presence or absence of HBV in renal tissue from patients with IgA nephropathy results in significant differences in the clinical features, types and severity of pathological lesions and, consequently, prognosis. Tissue deposition of HBV might play an aetiological role in the pathogenesis of IgA nephropathy and may be an exacerbating factor in renal progressive deterioration. Antiviral therapy could be an important intervention in HBV antigen-positive patients.     

Acute reversible renal failure with macroscopic haematuria in IgA nephropathy

Macroscopic haematuria is common in IgA nephropathy, but itssignificance and influence on prognosis remains uncertain. Wecompared the clinical and pathological features of 11 adultpatients with primary IgA nephropathy who had had a renal biopsyduring or shortly after a bleeding episode. Six patients developedtransient acute renal failure (ARF) (group 1) and five did not(group 2). Patients of group 1 had a higher percentage of tubularred-blood-cell (RBC) casts (P<0.05) and of glomerular crescents(P<0.001). However, crescents were focal and involved lessthan 50% of glomeruli. Acute tubular necrosis was only presentin patients of group 1, and ARF was attributed to the acutetubular changes rather than to the glomerular lesions. Despitea prolonged duration of ARF (mean: 38 days), further outcomedid not differ in patients of both groups. We suggest that acutetubular damage and/or tubular obstruction by RBC casts shouldbe considered in any patient who develops ARF soon after a haematuricepisode.