Oxford Classification System Research Articles

Diagnosing and Treating IgAN: Steroids, Budesonide, or Maybe Both?

IgA nephropathy (IgAN), the most common primary glomerulonephritis worldwide, is characterized by a mesangial IgA deposit and a variety of histological lesions, as described by the Oxford classification system. Despite the well-described "four-hit hypothesis", there are still plenty of less or undescribed mechanisms that participate in the disease pathogenesis, such as B-cell priming, which seems to be initiated by different antigens in the intestinal microbiota. Diagnosis of the disease is currently based on kidney biopsy findings, as the sensitivity and specificity of the many serum and urinary biomarkers described so far do not seem to have diagnostic accuracy. Therapeutic strategies consist of the initial step of non-immune medication, aiming to reduce both the intraglomerular pressure and proteinuria to below 0.5 g/day, followed by systemic corticosteroid administration in patients who remain at high risk for progressive chronic kidney disease despite the maximum non-immune treatment. The 6-month systemic corticosteroid treatment reduces proteinuria levels; however, the increased possibility of adverse events and increased relapse rate after treatment raises the need for a new therapeutic approach. Targeted-release budesonide is a therapeutic modality that aims to inhibit disease pathogenetic pathways at early stages; it has minor systemic absorption and proven beneficial effects on renal function and proteinuria. In the present systemic review, the benefits and adverse events of steroids and budesonide are described, and the possibility of combined treatment is questioned in selected cases with active histologic lesions.

Machine learning in predicting T-score in the Oxford classification system of IgA nephropathy.

Immunoglobulin A nephropathy (IgAN) is one of the leading causes of end-stage kidney disease (ESKD). Many studies have shown the significance of pathological manifestations in predicting the outcome of patients with IgAN, especially T-score of Oxford classification. Evaluating prognosis may be hampered in patients without renal biopsy. A baseline dataset of 690 patients with IgAN and an independent follow-up dataset of 1,168 patients were used as training and testing sets to develop the pathology T-score prediction (T pre) model based on the stacking algorithm, respectively. The 5-year ESKD prediction models using clinical variables (base model), clinical variables and real pathological T-score (base model plus T bio), and clinical variables and T pre (base model plus T pre) were developed separately in 1,168 patients with regular follow-up to evaluate whether T pre could assist in predicting ESKD. In addition, an external validation set consisting of 355 patients was used to evaluate the performance of the 5-year ESKD prediction model using T pre. The features selected by AUCRF for the T pre model included age, systolic arterial pressure, diastolic arterial pressure, proteinuria, eGFR, serum IgA, and uric acid. The AUC of the T pre was 0.82 (95% CI: 0.80-0.85) in an independent testing set. For the 5-year ESKD prediction model, the AUC of the base model was 0.86 (95% CI: 0.75-0.97). When the T bio was added to the base model, there was an increase in AUC [from 0.86 (95% CI: 0.75-0.97) to 0.92 (95% CI: 0.85-0.98); P = 0.03]. There was no difference in AUC between the base model plus T pre and the base model plus T bio [0.90 (95% CI: 0.82-0.99) vs. 0.92 (95% CI: 0.85-0.98), P = 0.52]. The AUC of the 5-year ESKD prediction model using T pre was 0.93 (95% CI: 0.87-0.99) in the external validation set. A pathology T-score prediction (T pre) model using routine clinical characteristics was constructed, which could predict the pathological severity and assist clinicians to predict the prognosis of IgAN patients lacking kidney pathology scores.

Correlation of pathologic findings of IgA nephropathy with clinical and laboratory data with regards to the Oxford-MEST-C classification

The Oxford classification system has been found to have significant correlations with clinical and laboratory data in patients with IgA nephropathy. Studies have shown that higher grades of mesangial hypercellularity and endocapillary hypercellularity are associated with younger age, higher blood pressure, and higher levels of proteinuria. Segmental glomerulosclerosis has been found to be associated with more severe proteinuria, lower serum albumin levels, and higher levels of creatinine. Tubular atrophy/interstitial fibrosis has been associated with older age, higher serum creatinine levels, and lower estimated glomerular filtration rates.

A mixed-method evaluation of the relationship between Oxford classification scores and longitudinal changes in proteinuria in patients with immunoglobulin A nephropathy.

This study aimed to investigate the relationship between Oxford Classification scores and longitudinal changes in proteinuria in patients with immunoglobulin A nephropathy (IgAN). The study was a single-center retrospective cohort study involving 358 patients with primary IgAN who were treated at the Shenzhen Second People's Hospital, China, between January 2011 and May 2021. Multivariate linear regression and generalized additive mixed models (GAMMs), adjusted for traditional risk confounders, were used to evaluate the correlation between scores for mesangial hypercellularity (M), endocapillary hypercellularity (E), segmental glomerulosclerosis (S), tubular atrophy/interstitial fibrosis (T), and crescents (C) (known as the Oxford Classification MEST-C score system), with proteinuria/creatinine ratio (PCR) at the time of renal biopsy and longitudinal changes in PCR, respectively. The median PCR was 1061 mg/g, and it increased on average by 68.82 mg/g per year in these patients. Among patients with renal insufficiency, compared with patients without relative lesions, those with E present (E1) (1153.44; 95% confidence interval [CI], 188.99-2117.89 mg/g) and C > 0 (C1/2) (1063.58; 95% CI, 185.25-1941.90 mg/g) were associated with increased PCR levels at the time of renal biopsy. What's more, S present (S1) (194.96; 95% CI, 54.50-335.43 mg/g per year) was associated with the fastest PCR increase; C > 0 (C1/2) (147.59; 95% CI, 8.32-286.86 mg/g per year) and T >25% (T1/2) (77.04; 95% CI, 7.18-146.89 mg/g per year), were also correlated with a faster PCR increase. In patients with normal kidney function, associations between S1 (55.46; 95% CI, 8.93-101.99 mg/g per year) and E1 (94.02; 95% CI, 21.47-166.58 mg/g per year) and PCR change could be observed. Additionally, in patients with overweight/obesity, S1 (156.09; 95% CI, 52.41-259.77 mg/g per year), E1 (143.34; 95% CI, 35.30-251.38 mg/g per year), T1/2 (116.04; 95% CI, 22.58-209.51 mg/g per year), as well as C1/2 (134.03; 95% CI, 41.73-226.32 mg/g per year) were associated with noticeably quicker PCR increase. Overall, E1 and C1/2 were independently associated with raised proteinuria levels at the time of renal biopsy, and S1, E1, T1/2, C1/2 were independently associated with a longitudinal increase in proteinuria in the patients with IgAN, especially in those with renal insufficiency or overweight/obesity, suggesting that currently available treatments might not be satisfactory, and weight control might be beneficial. Individual therapy development might benefit from the use of the Oxford Classification system.

Particulate matter of air pollution may increase risk of kidney failure in IgA nephropathy

IgA nephropathy (IgAN) is characterized by deposition of galactose-deficient IgA1 (Gd-IgA1) in glomerular mesangium associated with mucosal immune disorders. Since environmental pollution has been associated with the progression of chronic kidney disease in the general population, we specifically investigated the influence of exposure to fine particulate matter less than 2.5 μm in diameter (PM2.5) on IgAN progression. Patients with biopsy-proven primary IgAN were recruited from seven Chinese kidney centers. PM2.5 exposure from 1998 to 2016 was derived from satellite aerosol optical depth data and a total of 1,979 patients with IgAN, including 994 males were enrolled. The PM2.5 exposure levels for patients from different provinces varied but, in general, the PM2.5 exposure levels among patients from the north were higher than those among patients from the south. The severity of PM2.5 exposure in different regions was correlated with regional kidney failure burden. In addition, each 10 μg/m3 increase in annual average concentration of PM2.5 exposure before study entry (Hazard Ratio, 1.14; 95% confidence interval, 1.06-1.22) or time-varying PM2.5 exposure after study entry (1.10; 1.01-1.18) were associated with increased kidney failure risk after adjustment for age, gender, estimated glomerular filtration rate, urine protein, uric acid, hemoglobin, mean arterial pressure, Oxford classification, glucocorticoid and renin-angiotensin system blocker therapy. The associations were robust when the time period, risk factors of cardiovascular diseases or city size were further adjusted on the basis of the above model. Thus, our results suggest that PM2.5 is an independent risk factor for kidney failure in patients with IgAN, but these findings will require validation in more diverse populations and other geographic regions.

FC047: RNA Sequencing of Microdissected Kidney Biopsies from IGA Nephropathy Patients

Abstract BACKGROUND AND AIMS As the most common glomerulonephritis globally, mainly affecting younger adults and one of the most common causes of kidney failure [1], IgA Nephropathy (IgAN) poses an immense impact both on the individual and on the societal level. Here, we aimed to gain further molecular insight into the high interindividual variability of the clinical picture and disease progression by linking transcriptional profiling of IgAN-kidneys to clinical and histopathological data. METHOD Kidney biopsies from patients with histopathologically verified IgAN/IgA vasculitis (n = 84) (IgAV) [57 males, median (range) age of 39 (4–89) years] and 11 living donors (LD) [six males, median (range) age of 37 (30–65) years] were manually microdissected into glomerular and tubulointerstitial fractions. RNA was extracted with RNeasy lipid tissue mini kit (Qiagen, Valencia, CA, US) and evaluated using the Bioanalyzer 2100 (Agilent, Santa Clara, CA, US). mRNA purification, conversion to cDNA, fragmentation and double-stranded cDNA synthesis, amplification and clean-up were performed using Illumina Stranded mRNA prep ligation protocol (Illumina Inc). Paired-end RNA sequencing was performed in three different batches (Illumina Novaseq 6000). Data pre-processing was done using Trim Galore (v.0.6.4). Reads were aligned to the Ensembl GRCh38 reference genome using STAR (v2.6.1d). Gene counts were obtained using featureCounts (v1.5.1). Quality control was made using MultiQC (v.1.7). Comparisons between groups were performed using Bioconductor package DESeq2 (v1.22.2) and gene set enrichment analysis using Bioconductor package fgsea. The biopsies were evaluated by experienced renal pathologists using the Oxford classification [2] and the Banff classifications [3]. Clinical data at time of biopsy and 5-year follow-up was retrieved from patients’ files. Co-morbidity- and mortality data was extracted from the Swedish renal registry up to 19 years after the biopsy. RESULTS Principal Component Analysis showed clear separation between diseased and LD kidney transcriptomes, as well as between glomerular and tubulointerstitial fractions. Top upregulated genes in glomeruli were associated with complement activation and fibrosis. In tubulointerstium, top genes were related to the immune system, including chemokines. Gene ontology enrichment analysis highlighted immune response and complement activation in both compartments. Additionally, cell membrane and mitochondrial activity were enriched in tubulointerstium. Linking bioinformatic results to clinical data at the time of biopsy, progress over time as well as to histopathological data in accordance with the Oxford classification system [2] is ongoing. CONCLUSION This is, to our knowledge, the most comprehensive RNA sequencing performed on paired glomerular and tubulointerstitial tissue from patients with IgAN/IgAV. Initial bioinformatical analyses highlights biologically relevant processes involving different parts of the immune system. Our project has the potential to identify molecular processes associated with rapid disease progression and specific histopathological characteristics. This enables identification of patients with a more aggressive disease and individualized treatment depending on molecular profile, which would improve kidney survival and quality of life for patients suffering from IgAN/IgAV.

Serum Levels of miR-148b and Let-7b at Diagnosis May Have Important Impact in the Response to Treatment and Long-Term Outcome in IgA Nephropathy.

Background/aims: Previous studies showed that two microRNAs, let-7b and miR-148, which regulate the O-glycosylation process of IgA1, may predict diagnosis of primary IgA nephropathy (IgAN). The combined analysis of their serum levels in calculated statistical models may act as serum biomarkers for the diagnosis of primary IgAN. In the present study, we aimed to assess their impact not only on clinical and histological findings at onset but also on renal function after a long-term follow-up. Patients and methods: We enrolled 61 Caucasian patients with biopsy-proven IgAN. Serum levels of miR-148b, let-7b, and galactose-deficient IgA1 (Gd-IgA1) at the time of diagnosis were measured using real-time quantitative PCR and enzyme-linked immunosorbent assay using the monoclonal antibody KM55, respectively. Their values along with calculated Models 1 and 2 were correlated with histologic scoring system (Oxford classification system) and with renal function at diagnosis and after 11.9 ± 6.6 years. Fifty-five healthy volunteers were enrolled as controls. Results: No significant correlation was found between miRNA and Gd-IgA1 levels and eGFR and proteinuria at diagnosis. A significant negative association was detected between the presence of crescents and serum levels of let-7b (p = 0.002), miR-148b (p = 0.01), and Models 1 and 2 (p = 0.02 and p = 0.007, respectively). At the end of follow-up, eGFR correlated with let-7b levels (p = 0.01), Model 1 (p = 0.002), and Model 2 (p = 0.004). Patients with fast progression of the renal damage had significantly increased levels of let-7b (p = 0.01), Model 1 (p = 0.003), and Model 2 (p = 0.005) compared to slow progressors, as did those who reached ESKD (p = 0.002, p = 0.001, and p = 0.001, respectively). Results were most prominent in those treated with corticosteroids. Finally, cut off levels in Models 1 and 2 could also predict the renal function outcome after long-term follow-up. Conclusions: Serum levels of let-7b and miR-148b and their combination, may serve as predictors for long-term renal function outcomes, particularly in patients treated with corticosteroids.

Grading system utilising the total score of Oxford classification for predicting renal prognosis in IgA nephropathy

The Oxford classification of IgA nephropathy (IgAN) can evaluate each MEST-C score individually. We analysed a new grading system that utilised the total MEST-C score in predicting renal prognosis. Altogether, 871 IgAN patients were classified into three groups using the new Oxford classification system (O-grade) that utilised the total MEST-C score (O-grade I: 0–1, II: 2–4, and III: 5–7 points), and the 10-year renal prognosis was analysed. The clinical findings became significantly severer with increasing O-grades, and the renal survival rate by the Kaplan–Meier method was 94.1%, 86.9%, and 74.1% for O-grades I, II, and III, respectively. The hazard ratios (HRs) for O-grades II and III with reference to O-grade I were 2.8 (95% confidence interval [CI] 1.3–6.0) and 6.3 (95% CI 2.7–14.5), respectively. In the multivariate analysis, mean arterial pressure and eGFR, proteinuria at the time of biopsy, treatment of corticosteroids/immunosuppressors, and O-grade (HR 1.63; 95% CI 1.11–2.38) were the independent factors predicting renal prognosis. Among the nine groups classified using the O-grade and Japanese clinical-grade, the renal prognosis had an HR of 15.2 (95% CI 3.5–67) in the severest group. The O-grade classified by the total score of the Oxford classification was associated with renal prognosis.

Reading and Writing Strategies Used by Typical and Struggling Readers: A Cross-Sectional Survey

Reading and writing are essential skills to master for university students, as research has shown that effective use of reading and writing strategies can lead to academic success. There are contradictory studies regarding whether reading and writing strategies differ between typical and struggling higher education students. The present study aims to compare the quantities variations of learning strategies and the qualities variations to the strategy between typical and struggling students in Greek higher education. It is a cross-sectional survey. The sampling was convenient, consisted of 233 undergraduate Greek students; 46 were self-reported as struggling readers. The research instruments employed in the present study were two scales for reading and writing strategies usage, based on Oxford (1990) classification system. The results suggest that typical students tend to considerably use reading and writing strategies more often than struggling students. Although these students use fewer reading and writing strategies, they tend to use cognitive and metacognitive strategies.

Validation of the Macroscopic Anterior Cruciate Ligament Status Using the Oxford Classification System in Relation to Cartilage Defects on the Medial Tibial Plateau in Osteoarthritic Knees.

This study evaluated the relationships between anterior cruciate ligament (ACL) grading using the Oxford classification system and cartilage defects on the medial tibial plateau to clarify the validity of the system. We studied the location and size of a full-thickness cartilage defect of the medial tibial plateau in 154 knees (97 patients) treated by unicompartmental (113) or total (41) knee arthroplasty between April 2017 and January 2018, and analyzed their relationship to the anterior cruciate ligament (ACL) grade, Grade 1 (normal), Grade 2 (synovial damage), Grade 3 (longitudinal split), Grade 4 (friable and fragmented), and Grade 5 (absent). Significant trends in decreased posterior preserved cartilage, increased defect length, and posteriorized defect center were associated with increasing ACL grade. Multiple comparison analysis revealed that the measurements were significantly different between ACL functional (Grades 1-3) and ACL deficient (Grades 4 and 5). On the other hand, the anterior preserved cartilage was consistent among the Grades. The macroscopic Oxford ACL classification system well described the disease progression where the cartilage defect extends posteriorly with ACL damage. However, 38% of ACL deficient knees had well-preserved posterior cartilage with no evident tibial anterior translation.

A retrospective analysis of children with Henoch-Schonlein purpura and re-evaluation of renal pathologies using Oxford classification.

Henoch-Schönlein purpura (HSP) is the most common vasculitis in childhood. The long-term prognosis is variable and depends on renal involvement. The aims of this study were to investigate the clinical and laboratory characteristics of our HSP patients, to identify the risk factors for the development of Henoch-Schönlein purpura nephritis (HSPN) and to assess the efficacy of the Oxford Classification system for predicting renal outcomes. We performed a retrospective review of HSP patients who admitted to our center between 2001 and 2016, and were < 18years on admission. A total of 1120 children with HSP were analyzed. Their mean age was 7.4 ± 3.4years. At onset, purpura was present in all cases, arthritis/arthralgia in 42.4%, abdominal involvement in 39% and renal involvement in 37%. Risk factors for the development of nephritis were age ≥ 8years, atypical distribution of purpura, ESR > 20mm/h and abdominal pain. Renal biopsy was performed on 75 patients before immunosuppressive treatment. The mesangial score was strongly associated with proteinuria. Segmental glomerulosclerosis, tubular atrophy/interstitial fibrosis, and crescent formation of ≥ 50% were associated with reduced eGFR at the time of biopsy. A Kaplan-Meier plot showed that segmental glomerulosclerosis and tubular atrophy/interstitial fibrosis significantly predict poor renal outcome. The long-term morbidity of HSP is predominantly attributed to renal involvement. Patients with HSP, who have a high risk to develop nephritis, could be followed for longer periods of time. The Oxford classification is useful in predicting long-term outcomes of HSPN.

Evaluation of Clinical and Pathological Characteristics of Patients with IgA Nephropathy Based on Oxford Classification System: Should Crescents be Included?

AbstractIntroduction. None of the classification systems in immunoglobulin A (IgA) nephropathy has been widely agreed or implemented by clinicians or pathologists. In order to meet this need, "Oxford Classification System", which is highly reproducible and predictive for clinical course, was developed in 2009. In the present study, we investigated clinical and pathological characteristics of patients with IgA nephropathy based on current classification and the predictivity of crescent presence on prognosis. Methods. The study comprised 40 patients with diagnosis of primary IgA nephropathy on renal biopsy. The biopsy findings and follow-up parameters of patients were retrospectively re-evaluated. Pathological findings were examined based on the Oxford classification system. The presence of crescent formation in the specimens was noted. Results. The presence of crescent formation was predictive of poor prognosis regarding the glomerular filtration rate (eGFR), the level of proteinuria, and mean arterial pressure (MAP). Conclusion: Considering the importance of crescent formation in prediction of the clinical course and need for immunosuppressive therapy, it is suggested that crescent presence can be included in this classification system.

The Japanese Histologic Classification and T-score in the Oxford Classification system could predict renal outcome in Japanese IgA nephropathy patients.

The Oxford Classification is utilized globally, but has not been fully validated. In this study, we conducted a comparative analysis between the Oxford Classification and Japanese Histologic Classification (JHC) to predict renal outcome in Japanese patients with IgA nephropathy (IgAN). A retrospective cohort study including 86 adult IgAN patients was conducted. The Oxford Classification and the JHC were evaluated by 7 independent specialists. The JHC, MEST score in the Oxford Classification, and crescents were analyzed in association with renal outcome, defined as a 50% increase in serum creatinine. In multivariate analysis without the JHC, only the T score was significantly associated with renal outcome. While, a significant association was revealed only in the JHC on multivariate analysis with JHC. The JHC and T score in the Oxford Classification were associated with renal outcome among Japanese patients with IgAN. Superiority of the JHC as a predictive index should be validated with larger study population and cohort studies in different ethnicities.

Plasma Gelsolin Promotes Proliferation of Mesangial Cell in IgA Nephropathy

Background/Aims: Plasma gelsolin (pGSN) is an actin-binding protein that plays a critical role in the pathogenesis of rheumatoid arthritis. However, whether pGSN is involved in other immunological diseases remains unknown. This study focused on the relationship between pGSN and immunoglobulin A (IgA) nephropathy (IgAN). Methods: Two hundred patients with IgAN, 200 patients each with several other types of nephropathy and healthy controls (HCs) who underwent kidney biopsies between 2000 and 2014 were enrolled in the study. The Oxford classification system was used to predict the risk of disease progression. Serum and renal tissue were used to detect pGSN, and the correlations between pGSN and IgA, galactose-deficient IgA1 (Gd-IgA1), transforming growth factor beta1 (TGF-β1), fibronectin (FN) content, clinical symptoms, and kidney function were analyzed. Results: We found that the pGSN levels were significantly decreased in sera from IgAN patients compared to sera from patients with other forms of glomerular nephritis and HCs. Furthermore, the serum pGSN levels were negatively correlated with the serum IgA1, FN, and TGF-β1 levels, and positively correlated with the estimated glomerular filtration rate. Conversely, the glomerular pGSN content was significantly elevated in the IgAN patients and was positively correlated with TGF-β1 and FN levels. In renal tissue, the pGSN levels were significantly higher in IgAN patients with M1 and S1 compared to patients with M0 and S0 (p < 0.05). Meanwhile, pGSN promoted human mesangial cell (HMC) proliferation by facilitating cell mitosis in vitro. pGSN also promoted integrin α2β1 expression in HMCs and enhanced the integrin α2β1-pGSN interaction. Conclusion: Our study suggested that pGSN may play an important role in the development of IgAN by promoting the proliferation of mesangial cells and that serum and glomerular pGSN levels may be new markers for predicting IgAN progression and prognosis.

External validation of the Oxford classification of IgA nephropathy: A retrospective study of 70 patients from Saudi Arabia

The validity of the Oxford classification of immunoglobulin (Ig)A nephropathy has not been fully explored in the Arab population. The aim of this study was to assess the validity of this classification in a cohort of adult Saudi patients with histologically proven IgA nephropathy. A retrospective review of clinical and histological data of patients with biopsy-proven IgA nephropathy diagnosed between May 1998 and May 2011 was undertaken. The study was conducted at two institutions in Riyadh, Saudi Arabia. A total of 70 patients (46% females) with primary IgA nephropathy were included, with a mean age of 32.2 ± 12.9 years. The median follow-up was 3.5 years. The primary endpoint was decreased renal function, which was defined as 50% decrease in estimated glomerular filtration rate from baseline at last follow up. Higher mesangial score and later stage of segmental glomerulosclerosis showed trends towards correlations with a higher degree of proteinuria and lower estimated glomerular filtration rate at presentation and a higher rate of worsening of renal function, but these trends did not reach statistical significance ( p > 0.05). However, endocapillary hypercellularity and tubular atrophy/interstitial fibrosis were significantly associated with reduced initial estimated glomerular filtration rate and higher initial proteinuria. In multivariate logistic regression, the worsening of renal function was not predicted by any histologic class. The Oxford classification system is a useful tool that reflects the severity of the initial clinical presentation in Arabs with IgA nephropathy. However, it did not predict long-term renal outcomes. 在阿拉伯人群中，IgA 腎病變的牛津分類法尚未通過充分的驗證。本研究以經過組織學驗證為 IgA 腎病變的沙烏地阿拉伯成年患者為對象，對此分類法的效度進行了評估。 是次分析所涉及的個案，是從 1998 年 5 月至 2011 年 5 月間，經切片證實為原發性 IgA 腎病變的 70 位患者，女性佔 46%，平均年齡 32.2 ± 12.9 歲，均來自沙烏地阿拉伯利雅得的兩家院所。追蹤期間中位數為 3.5 年，首要終點為腎功能下降，其定義為腎小球濾過速率 (GFR) 估算值降幅達 50% (相對於基線)。 分析顯示，環間膜評分偏高、與較晚期節段性腎小球硬化症，均與以下呈現相關的傾向：基線較嚴重的蛋白尿、基線較低的 GFR 估算值、及追蹤期間較明顯的腎功能惡化，雖然未達統計學意義 ( p > 0.05)。然而，微血管內細胞過多、及腎小管萎縮/間質纖維化，則與基線較嚴重的蛋白尿、及基線較低的 GFR 估算值呈明顯關聯。在多變項邏輯迴歸分析中，組織學分類並未能預測腎功能惡化的發生。 對於阿拉伯的 IgA 腎病變成年患者，牛津分類法可有效反映初期的病情嚴重性，但未能預測腎功能的長期變化。

Up-regulation of urinary markers predict outcome in IgA nephropathy but their predictive value is influenced by treatment with steroids and azathioprine

Steroids and immunosuppressants can delay progression of renal function in IgAN, but their possible effect in local cytokines has not been studied. Histology in 53 IgAN patients (M/F 35/18 age 40.5 years (17 - 65)) was evaluated using the Oxford classification system. IL-1β, -2, -4, -5, -6, -10, -12 and -17, INF-γ and MCP-1 were measured subsequently by multiplex cytokine assay in first morning urine samples taken at the day of renal biopsy. After a 6-month course with RAASinhibitors + fish oils (FO), 35/53 patients, Group A, responded and continued on the same treatment, while in 18/53 who did not respond, Group B, steroids + azathiopine were added. The presence of endocapillary proliferation had significant correlation with the urinary excretion of pro-inflammatory and pro-fibrotic cytokines (IL-1β, MCP-1, IL-17, INF-γ, IL-6 and IL-10). Serum creatinine at time of diagnosis had significant correlation with proteinuria (p = 0.02), urinary levels of IL-1β (p = 0.03), IL-2 (p = 0.01) and MCP-1 (p = 0.03). GFR was reduced from 65 ± 29 to 57 ± 34 ml/min, p = 0.005 in Group A and remained stable in Group B patients (GFR from 63 ± 24 to 61 ± 30 ml/min, p = NS). Most of the measured cytokines in the urine predicted deterioration of renal function in Group A, but the urinary excretion of IL-6 seemed to predict renal function outcome in both groups of patients. Several cytokines are excreted in the urine of patients with IgAN, and their levels predict the outcome of the disease. Steroids + aza may exert their beneficial effect through suppression of the production or activation of most cytokines.

Evaluation of the Oxford Classification of IgA Nephropathy: A Systematic Review and Meta-analysis

The Oxford Classification of the pathology of immunoglobulin A (IgA) nephropathy, developed in 2009, is highly predictive of renal prognosis. It has been validated in different populations, but the results remain inconsistent. Systematic review and meta-analysis. Patients with biopsy-proven primary IgA nephropathy. Studies assessing the Oxford Classification of IgA nephropathy published between January 2009 and December 2012 were included following systematic searching of the MEDLINE and EMBASE databases. 4 pathologic lesions of the Oxford Classification: mesangial hypercellularity (M), endocapillary hypercellularity (E), segmental glomerulosclerosis (S), and tubular atrophy/interstitial fibrosis (T). Kidney failure defined as doubled serum creatinine level, 50% decline in estimated glomerular filtration rate, or end-stage kidney disease. 16 retrospective cohort studies with 3,893 patients and 570 kidney failure events were included. In a multivariate model, HRs for kidney failure were 0.6 (95% CI, 0.5-0.8; P < 0.001), 1.8 (95% CI, 1.4-2.4; P < 0.001), and 3.2 (95% CI, 1.8-5.6; P < 0.001) for scores of M0 (mesangial hypercellularity score ≤0.5), S1 (presence of segmental glomerulosclerosis), and T1/2 (>25% tubular atrophy/interstitial fibrosis), respectively, without evidence of heterogeneity. Pooled results showed that E lesions were not associated with kidney failure (HR, 1.4; 95% CI, 0.9-2.0; P = 0.1), with evidence of heterogeneity (I(2) = 54.1%; P = 0.01). Crescent (C) lesions were associated with kidney failure (HR, 2.3; 95% CI, 1.6-3.4; P < 0.001), with no evidence of heterogeneity (I(2) = 14.7%; P = 0.3). All studies were retrospective. This was not an individual-patient-data meta-analysis. This study suggests that M, S, T, and C lesions, but not E lesions, are associated strongly with progression to kidney failure and thus should be included in the Oxford Classification system.

Globally sclerotic glomeruli in IgA nephropathy patients.

Implication for health policy/practice/research/medical education:Oxford classification system was based on actual clinical data, international collaboration, and validation of the reproducibility of defining pathologic lesions. The strongest pathologic predictor of clinical outcome in IgA nephropathy is the extent of tubular atrophy and interstitial fibrosis.

Validation of the Oxford Classification of IgA Nephropathy: A Single-Center Study in Korean Adults

Background/AimsThe recently published Oxford classification of IgA nephropathy (IgAN) proposed a split system for histological grading, based on prognostic pathological features. This new classification system must be validated in a variety of cohorts. We investigated whether these pathological features were applicable to an adult Korean population.MethodsIn total, 69 adult Korean patients with IgAN were analyzed using the Oxford classification system at Soonchunhyang University Hospital, Seoul, Korea. All cases were categorized according to Lee's classification. Renal biopsies from all patients were scored by a pathologist who was blinded to the clinical data for pathological variables. Inclusion criteria were age greater than 18 years and at least 36 months of follow-up. We excluded cases with secondary IgAN, diabetic nephropathy combined other glomerulopathies, less than 36 months of follow-up, and those that progressed rapidly.ResultsThe median age of the patients was 34 years (range, 27 to 45). Mean arterial blood pressure was 97 ± 10 mmHg at the time of biopsy. The median follow-up period was 85 months (range, 60 to 114). Kaplan-Meier analysis showed significant prognostic predictions for M, E, and T lesions. A Cox proportional hazard regression analysis also revealed prognostic predictions for E and T lesions.ConclusionsUsing the Oxford classification in IgAN, E, and T lesions predicted renal outcome in Korean adults after taking clinical variables into account.

Focal segmental glomerulosclerosis plays a major role in the progression of IgA nephropathy. II. Light microscopic and clinical studies

It is well known that lesions morphologically identical with focal segmental glomerulosclerosis (FSGS) may appear in IgA nephropathy (IgAN). Capsular adhesions without underlying abnormalities in the tuft, often the first sign of FSGS, are frequent in IgAN. In this retrospective study, a new cohort of 128 adult patients with IgAN was used to validate the new Oxford classification system of IgAN, and shown to have highly significant associations with clinical and outcome parameters. We then used these patients to determine the extent to which IgAN could be accounted for in terms of FSGS. Some form of lesion consistent with FSGS, notably hyalinosis and collapsing glomerulopathy, was found in 101 of these patients. No glomerular lesions were found in 16 patients, and 11 had mild lesions not definable as FSGS. Those with FSGS had significantly worse renal survival at 80 months than those without. Comparison of pure forms of FSGS (excluding collapsing glomerulopathy) with cases of FSGS having other glomerular lesions (mesangial hyperplasia, endocapillary hypercellularity, glomerular necroses, extracapillary proliferation) revealed that those with FSGS and other superimposed lesions did significantly worse than cases of pure FSGS at 80 months following diagnosis. Importantly, patients with pure FSGS had relatively poor survival even without other superimposed glomerular abnormalities. Thus, the majority of cases of IgAN can be interpreted as representing one or another variant of FSGS. Hence, interpreting IgAN in terms of FSGS emphasizes the role that podocyte lesions may play in the pathogenesis and progression of this disease.