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.

The prognostic value of two histopathologic classification models of ANCA-associated glomerulonephritis: a prospective study.

BACKGROUND: Berden Classification and anti-neutrophil cytoplasmic antibody (ANCA) Renal Risk Score are classification models for rating renal histology and predicting outcome in patients with ANCA-associated Vasculitis/Glomerulonephritis (AAV/GN). In the present study we compare their ability to predict renal function outcome in short- and long-term follow up. METHODS: Patients with an initial diagnosis of AAV/GN based on kidney biopsy were classified according to Berden and Renal Risk Score, started on the same treatment protocol, and were followed prospectively for up to 60 months. Renal function was recorded at 3mo(T3), 6mo(T6) and 60mo(T60), and results were compared to both classification systems. RESULTS: Ninety four AAV/GN patients, M/F = 36/58, age = 60.05 (18-82)yrs were included. Based on Berden classification, patients grouped as Focal (n = 24), Crescentic (n = 35), Mixed (n = 21) and Sclerotic (n = 14), had significant differences in estimated glomerular filtration rate (eGFR) only at T3, while the percentage of those requiring hemodialysis differed at T0, T3, T6 but not at T60. According to the Renal Risk Score, patients were classified as Low (n = 8), Medium (n = 47) and High (n = 39) risk, and showed significant differences in both eGFR levels, proportion of hemodialysis, at T0, T3, T6 and end-stage kidney disease (ESKD) at T60. Even patients classified as Mixed (Berden) and as Medium or High risk (Renal Risk Score) had significant improvement from T0 to T6. Relapse could not be predicted by either system. CONCLUSION: Both methods were able to predict short-term renal function outcome and need for hemodialysis, but the Renal Risk Score showed significant superiority in predicting renal function outcome and ESKD after long-term follow up.

Multidisciplinary approach to lupus nephritis: Clinical pearls, pitfalls, and positioning of newly-approved agents.

Lupus nephritis (LN) is a major course of morbidity and mortality in patients with systemic lupus erythematosus (SLE), best managed by a multidisciplinary group. To this end, we gathered a group of rheumatologists, nephrologists and a nephropathologist to review current evidence regarding diagnosis and management of LN. In this consensus paper, we summarize the key points from this meeting and provide practice guidelines for the management of kidney involvement in SLE, in view of emerging new data concerning novel agents approved recently. Renal biopsy is indispensable for the management of LN. Yet, important pearls and pitfalls need to be considered regarding indications and interpretation, which are summarized in informative tables. In new-onset LN, experts agreed that, although belimumab may be added from disease onset, patients with moderate to severe proliferative nephritis (defined as: NIH activity index > 5 plus ≥ 1 of the following: (i) NIH chronicity index > 2, (ii) proteinuria > 3 g/24 h, and (iii) increase in serum creatinine > 20%) may be more likely to benefit the most. In all other patients who have already started standard-of-care treatment with either mycophenolate mofetil (MMF) or cyclophosphamide (CY), belimumab could be considered in cases with an inadequate clinical response by 3 months, or in cases that experience a nephritic flare following initial response, or have an inability to reduce the dose of glucocorticoids. In all circumstances, the drug should be given as add-on therapy, that is, in combination with a standard-of-care therapy (MMF or CY). Voclosporin could be considered for up to 3 years, in combination with MMF, in patients with heavy proteinuria (well above the nephrotic range), wherein a quick reduction of protein loss in urine is desirable to avoid the complications of the nephrotic syndrome, either as part of the initial regimen, or in cases of inadequate reduction of proteinuria with MMF. In view of the potential scarring effects, long-term administration beyond the first year requires further documentation.

Relapse of Monoclonal Gammopathy of Renal Significance after mRNA COVID-19 Vaccination: A Case Report.

This case report represents the first suspected case of light chain deposition disease relapse associated with mRNA COVID-19 vaccination. The 75-year-old female patient of Greek ethnicity was admitted to the clinic for the investigation of worsening renal function detected on routine lab examinations, two weeks after she received the second dose of the Moderna COVID-19 vaccine (mRNA-1273). Rapidly progressive glomerulonephritis and anemia were the most notable findings. She had a history of LCDD, which had remained stable for four years. Serum protein immunofixation showed monoclonal kappa zones, and a bone marrow biopsy revealed 5% plasma cell infiltration. These, along with other investigations, established the diagnosis of LCDD recurrence. The patient was started on chemotherapy, which improved her immunological profile, but not her renal function. The patient has remained on hemodialysis since. The association between mRNA vaccinations and LCDD relapse may be grounds for investigations into the pathophysiology of MGRS, given the patient's previous long-term remission. This case report is not intended to directly inform changes in clinical practice. We must stress the importance of following all standardized vaccination protocols, especially in immunocompromised patients.

From KDIGO 2012 towards KDIGO 2021 in idiopathic membranous nephropathy guidelines: what has changed over the last 10 years?

The recommendations in the Kidney Disease: Improving Global Outcomes (KDIGO) 2021 guidelines regarding Idiopathic Membranous Nephropathy (IMN) management include significant changes as compared to those published in 2012. According to the recent guidelines, a biopsy is not always needed for IMN diagnosis; since diagnosis can be allowed for by the detection of circulating antibodies against the M-type transmembrane phospholipase A2 receptor (anti-PLA2R). Moreover, alterations in anti-PLA2R concentrations, along with other serum and urinary markers, may guide further follow-up. The findings of numerous recent studies which compared different immunosuppressive treatments resulted in substantial changes in treatment indications in the KDIGO 2021 guidelines, suggesting the stratification of patients into four risk categories. The definition of resistant cases and relapses was likewise modified. All the above will lead to a more granular and personalized approach, whose results need to be tested over time. In this commentary, we discuss the changes in the 2012 and 2021 guidelines, adding information from the most recent literature.

Post-hoc analysis of a tool to predict kidney failure in patients with IgA nephropathy.

BACKGROUND: Recently, a tool based on two different artificial neural networks has been developed. The first network predicts kidney failure (KF) development while the second predicts the time frame to reach this outcome. In this study, we conducted a post-hoc analysis to evaluate the discordant results obtained by the tool. METHODS: The tool performance was analyzed in a retrospective cohort of 1116 adult IgAN patients, as were the causes of discordance between the predicted and observed cases of KF. RESULTS: There was discordance between the predicted and observed KF in 216 IgAN patients (19.35%) all of whom were elderly, hypertensive, had high serum creatinine levels, reduced renal function and moderate or severe renal lesions. Many of these patients did not receive therapy or were non-responders to therapy. In other IgAN patients the tool predicted KF but the outcome was not reached because patients responded to therapy. Therefore, in the discordant group (prediction did not match the observed outcome) the proportion of patients having or not having KF was strongly associated with treatment (P < 0.0001). CONCLUSIONS: The post-hoc analysis shows that discordance in a low number of patients is not an error, but rather the effect of positive response to therapy. Thus, the tool could both help physicians to determine the prognosis of the disease and help patients to plan for their future.

Type of ANCA May Be Indispensable in Distinguishing Subphenotypes of Different Clinical Entities in ANCA-Associated Vasculitis.

The traditional nomenclature system for classifying antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) based on clinical phenotype describes granulomatosis with polyangiitis (GPA), eosinophilic granulomatosis with polyangiitis (EGPA) and microscopic polyangiitis (MPA) as distinct clinical entities. This classification has proved its expedience in clinical trials and everyday clinical practice; yet, a substantial overlap in clinical presentation still exists and often causes difficulties in prompt definition and clinical distinction. Additionally, new insights into the AAV pathogenesis point out that PR3 and MPO-AAV may not represent expressions of the same disease spectrum but rather two distinct disorders, as they display significant differences. Thus, it is supported that a classification based on ANCA serotype (PR3-ANCA, MPO-ANCA or ANCA-negative) could be more accurate and also closer to the nature of the disease compared to the phenotype-based one. This review aims to elucidate the major differences between PR3 and MPO-AAV in terms of epidemiology, pathogenesis, histological and clinical manifestations and response to therapeutic approaches.

A patient with dialysis-dependent acute kidney injury due to hantavirus complicated with SARS-CoV-2 infection.

In this case, we report a 64-year-old man presenting with anorexia, nausea and vomiting, mild abdominal pain, and oligoanuria for a few hours. His previous medical history included diabetes, hypertension, and chronic kidney disease (CKD) stage 3. Upon arrival, laboratory results revealed stage III acute kidney injury (AKI) with hyperkalemia requiring dialysis treatment. During hospitalization, both pre-renal and post-renal causes of AKI were excluded, and a careful diagnostic evaluation, including kidney biopsy and serology testing, revealed acute interstitial nephritis and positive IgM for hantavirus. The patient was started on steroid treatment, which led to complete recovery of kidney function over 3 months. Moreover, during his hospitalization, the patient was also diagnosed with SARS-CoV-2 infection, possibly due to intra-hospital transmission and was hospitalized at the COVID-19 Department for 14 days, eventually with no further complications. Hantavirus nephropathy should be at the differential diagnosis of AKI, even in the absence of typical symptoms. Steroid treatment may be helpful in reversal of kidney injury.

De novo Minimal Change Disease in an Adolescent after Pfizer-BioNTech COVID-19 Vaccination: A Case Report.

This is the first report in an adolescent of minimal change disease (MCD) after the first injection of the BNT162b2 COVID-19 vaccine (Pfizer-BioNTech) with complete remission following steroid treatment. An 18-year-old white male with no prior medical history complained of gastrointestinal symptoms 11 days after his vaccination. Ascites and lower extremity edema were observed a few days later. He was admitted to a hospital as laboratory testing revealed proteinuria of 10.5 g/24 h, normal creatinine levels, and serum albumin of 1.8 g/dL, confirming the presence of nephrotic syndrome. Immunology and serology tests were unremarkable. A diagnostic kidney biopsy showed no significant glomerular or tubular abnormalities in light microscopy with negative immunofluorescence. Treatment with methylprednisolone 48 mg daily was initiated. A week after discharge, proteinuria declined to 1.2 g/24 h, and edema had disappeared, and 6 weeks later, complete remission was evident. As COVID-19 vaccination has been associated with the development of de novo and relapsing MCD, and this case provides additional support for this possible correlation.

Histology and Immunohistochemistry of Radial Arteries Are Suggestive of an Interaction between Calcification and Early Atherosclerotic Lesions in Chronic Kidney Disease.

Background and Objectives: recent studies suggest an implication of immune mechanisms in atherosclerotic disease. In this paper, the interaction between inflammation, calcification, and atherosclerosis on the vessel walls of patients with chronic kidney disease (CKD) is described and evaluated. Materials and Methods: patients with stage V CKD, either on pre-dialysis (group A) or on hemodialysis (HD) for at least 2 years (group B), in whom a radiocephalic arteriovenous fistula (RCAVF) was created, were included in the study. The control group included healthy volunteers who received radial artery surgery after an accident. The expressions of inflammatory cells, myofibroblasts, and vascular calcification regulators on the vascular wall were estimated, and, moreover, morphometric analysis was performed. Results: the expressions of CD68(+) cells, matrix carboxyglutamic acid proteins (MGPs), the receptor activator of nuclear factor-kB (RANK) and RANK ligand (RANKL), and osteoprotegerin (OPG), were significantly increased in CKD patients compared to the controls p = 0.02; p = 0.006; p = 0.01; and p = 0.006, respectively. In morphometric analysis, the I/M and L/I ratios had significant differences between CKD patients and the controls 0.3534 ± 0.20 vs. 0.1520 ± 0.865, p = 0.003, and 2.1709 ± 1.568 vs. 4.9958 ± 3.2975, p = 0.03, respectively. The independent variables correlated with the degree of vascular calcification were the intensity of CD34(+), aSMA(+) cells, and OPG, R2 = 0.76, p < 0.0001, and, with intima-media thickness (IMT), the severity of RANKL expression R2 = 0.3, p < 0.0001. Conclusion: atherosclerosis and vascular calcification in CKD seem to be strongly regulated by an immunological and inflammatory activation on the vascular wall.

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.

Systemic complement activation in anti-neutrophil cytoplasmic antibody-associated vasculitis and necrotizing glomerulonephritis.

AIM: Due to the accumulating evidence of complement activation in anti-neutrophil cytoplasmic antibody (ANCA) associated vasculitis (AAV), we decided to investigate the possibility of systemic complement activation in patients with Necrotizing Glomerulonephritis secondary to AAV. METHODS: Clinical, laboratory and histological findings, and serum levels of complement components, C3a, C5a and Bb fragment of Factor B and C4d, were estimated in patients with AAV and glomerulonephritis, at time of diagnosis, before any treatment had been applied. All patients were treated with the same immunosuppressive protocol and followed up for total 24 months. Twenty age and sex matched healthy individuals served as controls. RESULTS: Serum levels of all complement components were significantly increased in patients, compared to controls; C5a: 19.9(0.02-48) vs 9.06(2.1-16.3)pg/mL, P = .002, Bb: 7.3(0.02-31.4) vs 0.2(0.02-1.6)pg/mL, P < .0001, C3a: 4.7(0.4-7.2) vs 2.4(1.09-5)pg/mL, P = .05 and C4d: 11.6(0.07-70) vs 0.7(0.07-8.2)pg/mL, P = .001, respectively. There was strong correlation between serum Bb levels and eGFR and FFS2009 score at time of diagnosis (r = -.41, P = .002 and r = .41, P = .003 respectively). Also, serum Bb levels were increased in patients with severe interstitial infiltration (P = .04) and focal necrosis (P = .01) on renal biopsy. Serum Bb levels could also predict renal function outcome during the acute phase of disease, but not at the end of follow up. CONCLUSION: We provided strong evidence of systemic activation of complement alternative pathway in the development and progression of AAV and glomerulonephritis. Serum Bb seem to play a critical role in the induction, also predicting disease activity and outcome, yet activation of classical pathway cannot be excluded.

The switch from proteasome to immunoproteasome is increased in circulating cells of patients with fast progressive immunoglobulin A nephropathy and associated with defective CD46 expression.

The proteasome to immunoproteasome (iPS) switch consists of ß1, ß2 and ß5 subunit replacement by low molecular weight protein 2 (LMP2), LMP7 and multicatalytic endopeptidase-like complex-1 (MECL1) subunits, resulting in a more efficient peptide preparation for major histocompatibility complex 1 (MHC-I) presentation. It is activated by toll-like receptor (TLR) agonists and interferons and may also be influenced by genetic variation. In a previous study we found an iPS upregulation in peripheral cells of patients with immunoglobulin A nephropathy (IgAN). We aimed to investigate in 157 IgAN patients enrolled through the multinational Validation Study of the Oxford Classification of IgAN (VALIGA) study the relationships between iPS switch and estimated glomerular filtration rate (eGFR) modifications from renal biopsy to sampling. Patients had a previous long follow-up (6.4 years in median) that allowed an accurate calculation of their slope of renal function decline. We also evaluated the effects of the PSMB8/PSMB9 locus (rs9357155) associated with IgAN in genome-wide association studies and the expression of messenger RNAs (mRNAs) encoding for TLRs and CD46, a C3 convertase inhibitor, acting also on T-regulatory cell promotion, found to have reduced expression in progressive IgAN. We detected an upregulation of LMP7/ß5 and LMP2/ß1 switches. We observed no genetic effect of rs9357155. TLR4 and TLR2 mRNAs were found to be significantly associated with iPS switches, particularly TLR4 and LMP7/ß5 (P < 0.0001). The LMP7/ß5 switch was significantly associated with the rate of eGFR loss (P = 0.026), but not with eGFR at biopsy. Fast progressors (defined as the loss of eGFR >75th centile, i.e. -1.91 mL/min/1.73 m2/year) were characterized by significantly elevated LMP7/ß5 mRNA (P = 0.04) and low CD46 mRNA expression (P < 0.01). A multivariate logistic regression model, categorizing patients by different levels of kidney disease progression, showed a high prediction value for the combination of high LMP7/ß5 and low CD46 expression.

Formalin-fixed paraffin-embedded renal biopsy tissues: an underexploited biospecimen resource for gene expression profiling in IgA nephropathy.

Primary IgA nephropathy (IgAN) diagnosis is based on IgA-dominant glomerular deposits and histological scoring is done on formalin-fixed paraffin embedded tissue (FFPE) sections using the Oxford classification. Our aim was to use this underexploited resource to extract RNA and identify genes that characterize active (endocapillary-extracapillary proliferations) and chronic (tubulo-interstitial) renal lesions in total renal cortex. RNA was extracted from archival FFPE renal biopsies of 52 IgAN patients, 22 non-IgAN and normal renal tissue of 7 kidney living donors (KLD) as controls. Genome-wide gene expression profiles were obtained and biomarker identification was carried out comparing gene expression signatures a subset of IgAN patients with active (N = 8), and chronic (N = 12) renal lesions versus non-IgAN and KLD. Bioinformatic analysis identified transcripts for active (DEFA4, TNFAIP6, FAR2) and chronic (LTB, CXCL6, ITGAX) renal lesions that were validated by RT-PCR and IHC. Finally, two of them (TNFAIP6 for active and CXCL6 for chronic) were confirmed in the urine of an independent cohort of IgAN patients compared with non-IgAN patients and controls. We have integrated transcriptomics with histomorphological scores, identified specific gene expression changes using the invaluable repository of archival renal biopsies and discovered two urinary biomarkers that may be used for specific clinical decision making.

Chronic Therapy with Sucroferric Oxyhydroxide Does Not Affect Iron and Anemia Markers in Dialysis Patients.

INTRODUCTION: Sucroferric oxyhydroxide (SOH) is an iron-based phosphate binder (PB), and its use has been widely expanded since its initial approval in 2014. Based on the existing data, however, it remains yet unclear whether its long-term administration is followed by iron overload in dialysis patients. The purpose of this observational study was to evaluate the longstanding effects of SOH on the anemia and iron indices in patients on dialysis. METHODS: A total of 110 patients from 3 dialysis centers were included in the study; 49 were under chronic treatment with SOH (cohort A), while 61 were either receiving other PB or no treatment for hyperphosphatemia (cohort B). We initially compared the hematologic profile of patients in 2 cohorts (phase I), and subsequently, we evaluated modifications of the above parameters in the SOH treated patients over a period of 6 months (phase II). RESULTS: There were no statistically significant differences between 2 cohorts in terms of hemoglobin (Hb; 11.4 ± 1.3 vs. 11.6 ± 0.9 g/dL, p = 0.375), ferritin (473 ± 230 vs. 436 ± 235 ng/mL, p = 0.419) and transferrin saturation (TSAT;26.6 ± 13.2 vs. 26.5 ± 10.6%, p = 0.675), serum phosphate concentration (4.57 ± 1.05 vs. 4.3 ± 0.96 mg/dL, p = ns), and intact PTH (286 ± 313 vs. 239 ± 296 pg/mL, p = ns). Marginally, but significantly higher calcium levels were found in cohort A compared to cohort B (9.18 ± 0.58 vs. 8.9 ± 0.51 mg/dL, respectively, p = 0.008). In phase II, no significant changes were observed in hematological parameters after a 6-month treatment with SOH (Hb: from 11.5 ± 1.1 to 11.4 ± 1.3 g/dL, p = 0.4, serum ferritin levels: from 475 ± 264 to 473 ± 230 ng/mL, p = 0.951, TSAT: from 26.5 ± 16.7 to 26.6 ± 13.2%, p = 0.933). There were also no significant changes in the administration of iron supplements or erythropoietin dose during this period. CONCLUSIONS: SOH is an effective PB, and its long-term use is not complicated by iron overload.

Is there long-term value of pathology scoring in immunoglobulin A nephropathy? A validation study of the Oxford Classification for IgA Nephropathy (VALIGA) update.

BACKGROUND: It is unknown whether renal pathology lesions in immunoglobulin A nephropathy (IgAN) correlate with renal outcomes over decades of follow-up. METHODS: In 1130 patients of the original Validation Study of the Oxford Classification for IgA Nephropathy (VALIGA) cohort, we studied the relationship between the MEST score (mesangial hypercellularity, M; endocapillary hypercellularity, E; segmental glomerulosclerosis, S; tubular atrophy/interstitial fibrosis, T), crescents (C) and other histological lesions with both a combined renal endpoint [50% estimated glomerular filtration rate (eGFR) loss or kidney failure] and the rate of eGFR decline over a follow-up period extending to 35 years [median 7 years (interquartile range 4.1-10.8)]. RESULTS: In this extended analysis, M1, S1 and T1-T2 lesions as well as the whole MEST score were independently related with the combined endpoint (P < 0.01), and there was no effect modification by age for these associations, suggesting that they may be valid in children and in adults as well. Only T lesions were associated with the rate of eGFR loss in the whole cohort, whereas C showed this association only in patients not treated with immunosuppression. In separate prognostic analyses, the whole set of pathology lesions provided a gain in discrimination power over the clinical variables alone, which was similar at 5 years (+2.0%) and for the whole follow-up (+1.8%). A similar benefit was observed for risk reclassification analyses (+2.7% and +2.4%). CONCLUSION: Long-term follow-up analyses of the VALIGA cohort showed that the independent relationship between kidney biopsy findings and the risk of progression towards kidney failure in IgAN remains unchanged across all age groups and decades after the renal biopsy.

Histological grading in primary membranous nephropathy is essential for clinical management and predicts outcome of patients.

AIMS: Diagnosis of primary membranous nephropathy (PMN) is mainly based on immunofluorescence/immunohistochemistry findings. However, assessment of specific features on optical microscopy can help to estimate the severity of the disease, guide treatment and predict the response. The aim of this study was to identify, classify and grade the precise histological findings in PMN to predict renal function outcome and guide treatment. METHODS AND RESULTS: Histological parameters, including focal segmental sclerosis (FSGS), tubular atrophy (TA), interstitial fibrosis (IF) and vascular hyalinosis (VH), were re-evaluated in 752 patients with PMN. Their predictive value was estimated separately, and also in a combination score (FSTIV) graded from 0 to 4. Finally, the impact of histology was assessed in the response to immunosuppressive treatment. Mean age of patients was 53.3 (15-85) years and most presented with nephrotic syndrome. FSGS was present in 32% and VH in 51% of the patients, while TA and IF were graded as stage ≥1 in 52% and 51.4%, respectively. The follow-up period was 122.3 (112-376) months. FSGS, TA and IF and VH were associated with impaired renal function at diagnosis (P = 0.02, P < 0.0001, P = 0.001 and P = 0.02, respectively) and at the end of follow-up (P = 0.004, P < 0.0001, P < 0.0001 and P = 0.04, respectively). In multiple regression and binary logistic analysis, the presence of FSGS and degree of TA were the most significant parameters predicting renal function outcome, defined either by eGFR (end), FSGS (r = 0.6, P < 0.0001) and TA (r = 0.6, P < 0.0001), or by the endpoint of >50% eGFR reduction, FSGS (P = 0.001) and TA (P = 0.02). Also, patients presented with FSGS, IF, VH and/or with FSTIV > 1 could benefit from immunosuppression, regardless of clinical presentation. CONCLUSIONS: The presence and degree of four histological indices, FSGS, VH, TA and IF, assessed separately or in combination, and FSTIV score not only predict renal function outcome after long-term follow-up, but can also help in the choice of appropriate treatment. Decisions concerning immunosuppressive treatment can be guided by pathology regardless of clinical findings.

Circulating anti-phospholipase A2 receptor antibodies as a diagnostic and prognostic marker in Greek patients with idiopathic membranous nephropathy - a retrospective cohort study.

INTRODUCTION: Circulating autoantibodies against phospholipase A2 receptor (anti-PLA2R) are recognized as key elements in the pathogenesis of idiopathic membranous nephropathy. In current clinical practice, they are increasingly gaining attention as novel tools for diagnosis and disease monitoring. We investigated the diagnostic and prognostic utility of anti-PLA2R antibody measurements in Greek patients with biopsy-proven membranous nephropathy. METHODS: Anti-PLA2R levels were measured in serum samples from 33 patients at diagnosis using ELISA and were associated with treatment outcome. Moreover, serial anti-PLA2R measurements were performed in 15 patients under different clinical conditions and level alterations were correlated with disease activity. RESULTS: Positive anti-PLA2R antibodies at diagnosis were found in 16 of 33 patients (48.5%). Anti-PLA2R levels were independently associated with the achievement of complete remission of nephrotic syndrome after immunosuppressive treatment compared to partial remission (p = 0.02, R2 = 0.265, 95%CI -0.019 to -0.0003). Higher detectable antibody levels at diagnosis were correlated with higher proteinuria levels (r = 0.813, p = 0.0001, 95%CI 0.532 to 0.933) and lower eGFR at the end of follow-up (r = -0.634, p = 0.0083, 95%CI -0.86 to -0.202). Serial antibody measurements during follow-up showed that anti-PLA2R titers were significantly reduced at the end of treatment after complete remission was achieved, remained low under sustained clinical remission, and increased during relapse. CONCLUSIONS: Our findings confirm the usefulness of anti-PLA2R measurements in the diagnosis of idiopathic membranous nephropathy. Low levels of anti-PLA2R antibodies at diagnosis are predictive of complete remission of nephrotic syndrome following immunosuppressive treatment. Serial anti-PLA2R measurements correlate well with clinical status throughout the follow-up period and could be used routinely for monitoring of disease activity and treatment planning.

Defective gene expression of the membrane complement inhibitor CD46 in patients with progressive immunoglobulin A nephropathy.

BACKGROUND: Complement is thought to play a role in immunoglobulin A nephropathy (IgAN), though the activating mechanisms are unknown. This study focused on the gene expression of CD46 and CD55, two key molecules for regulating C3 convertase activity of lectin and alternative complement pathways at a cellular level. METHODS: The transcriptional expression in peripheral white blood cells (WBCs) of CD46 and CD55 was investigated in 157 patients enrolled by the Validation of the Oxford Classification of IgAN group, looking for correlations with clinical and pathology features and estimated glomerular filtration rate (eGFR) modifications from renal biopsy to sampling. Patients had a previous median follow-up of 6.4 (interquartile range 2.8-10.7) years and were divided into progressors and non-progressors according to the median value of their velocity of loss of renal function per year (-0.41 mL/min/1.73 m2/year). RESULTS: CD46 and CD55 messenger RNA (mRNA) expression in WBCs was not correlated with eGFR values or proteinuria at sampling. CD46 mRNA was significantly correlated with eGFR decline rate as a continuous outcome variable (P = 0.014). A significant difference was found in CD46 gene expression between progressors and non-progressors (P = 0.013). CD46 and CD55 mRNA levels were significantly correlated (P < 0.01), although no difference between progressors and non-progressors was found for CD55 mRNA values. The prediction of progression was increased when CD46 and CD55 mRNA expressions were added to clinical data at renal biopsy (eGFR, proteinuria and mean arterial blood pressure) and Oxford MEST-C (mesangial hypercellularity, endocapillary hypercellularity, segmental glomerulosclerosis, tubular atrophy/interstitial fibrosis, presence of any crescents) score. CONCLUSIONS: Patients with progressive IgAN showed lower expression of mRNA encoding for the complement inhibitory protein CD46, which may implicate a defective regulation of C3 convertase with uncontrolled complement activation.

Impact of Τh1 and Τh2 cytokines in the progression of idiopathic nephrotic syndrome due to focal segmental glomerulosclerosis and minimal change disease.

BACKGROUND: Differential diagnosis between primary focal segmental glomerulosclerosis (FSGS) and minimal change disease (MCD) is sometimes difficult as nephrotic syndrome is the main clinical symptom in both diseases. OBJECTIVES: This study has attempted to evaluate the urinary excretion of Th1 and Th2 cytokines as potential biomarkers in distinguishing the two types of nephrotic syndrome, and predicting outcome of renal function. PATIENTS AND METHODS: Thirty-six patients with FSGS (M/F 22/14, Age; 41.9 ± 17 years, SCr=1.7 ± 0.8 mg/dL, UProt=4.7 ± 5.5 g/24 h), and 21 with MCD (M/F 5/16, Age; 41.4 ± 15 years, SCr = 1 ± 0.4 mg/dL, UProt = 7.9 ± 9.3 g/24 h) were included in the study. Τh1 (IL-2, IL-12, GM-CSF, INF-γ, TNF-α) and Th2 cytokines (IL-4, IL-5, IL-10, IL-13) were measured by multiple cytokine assay, Luminex technology, in first morning urinary samples collected at the day of renal biopsy. RESULTS: No significant differences in urinary excretion of all cytokines were found between FSGS and MCD patients. In FSGS however, IL-12 urinary levels were independent factor correlated with both global sclerosis (R = 0.5, P = 0.009) and interstitial fibrosis (R = 0.5, P = 0.02). Th1 cytokines (IL-2 and GM-CSF) were significantly increased in FSGS patients who did not respond to treatment (P = 0.03 and P = 0.007, respectively). Th2 cytokines (IL-4, IL-5, IL-10, IL-13) were significantly increased in MCD patients with frequent relapses (P = 0.05, P = 0.001, P = 0.01, P = 0.03). CONCLUSIONS: Urinary excretion of Th1 and Th2 cytokines cannot discriminate FSGS from MCD. Th1 cytokines, especially IL-12, IL-2 and GM-CSF, may be involved in pathology and progression of FSGS, while Th2 cytokines are implicated in frequent relapses of nephrotic syndrome in MCD.