Predictors of poor outcomes in steroid therapy for immunoglobulin A nephropathy

Background: Steroid therapy appears to be beneficial in patients of immunoglobulin A nephropathy (IgAN), as it causes a reduction in the proteinuria and improves the renal survival. Methods: A retrospective review of the 5 year follow‐up data of 60 patients with IgAN who were treated with steroids was conducted. Steroid non‐responders were defined as patients in whom the primary end‐point of a 30% decrease of the estimated glomerular filtration rate from baseline was reached. The patients were divided into two groups, namely, the steroid responder group (n = 47) and the steroid non‐responder group (n = 13), and the clinicopathophysiological characteristics were compared between the two groups. Results: Significant decrease of the proteinuria was observed in the responder group over the 5 year follow‐up period, whereas no significant change of the urinary protein excretion was observed in the non‐responder group during the same period. In regard to the pathological findings, significantly higher ratios of glomerular obsolescence and glomerular tuft adhesion to the Bowman's capsule, and significantly higher severity of interstitial fibrosis at the time of diagnosis in the non‐responder group than in the responder group were found. The rates of glomerular obsolescence and glomerular tuft adhesion to the Bowman's capsule, the severity of interstitial fibrosis, serum albumin and urinary protein excretion were identified as independent risk factors influencing the rate of renal function deterioration. Conclusion: To develop effective therapeutic modalities, it is important to have a thorough understanding of the clinicopathophysiological characteristics of IgAN patients showing poor treatment response to steroids (non‐responder group in this study).     

Predictors for progression in immunoglobulin A nephropathy with significant proteinuria

Aim: Proteinuria is a primary factor requiring treatment in immunoglobulin (Ig)A nephropathy. The purpose of this study was to assess the relevance of treatment response and relapse of proteinuria with renal function decline. Methods: One hundred and twenty‐five biopsy‐proven primary IgA nephropathy patients who had more than 1.0 g/day proteinuria at the first assessment were studied. All patients underwent anti‐proteinuric treatment, and the association of the rate of renal function decline with treatment responsiveness, clinical and laboratory data was investigated. Results: The treatment response of the patients was: 30.4% complete response (<0.3 g/day proteinuria), 32.8% partial response (0.3–1.0 g/day), 23.2% minimal response (decrement but not reduced to <1 g/day) and 13.6% no response (no decrement of proteinuria). The slope of renal function decline (?1.06 vs?1.24 mL/min per 1.73 m²/year, P = 0.580) was comparable between complete and partial response groups, but they were slower than those of minimal or non‐response groups (P < 0.001). In multivariate analysis including other parameters, mean arterial pressure (MAP; β = –0.240, P = 0.004) during follow up, minimal (β = –0.393, P < 0.001) and non‐response (β = –0.403, P < 0.001) were significant predictors. In further investigation of complete and partial response groups, MAP (β = –0.332, P = 0.001) and relapse of proteinuria (β = –0.329, P = 0.001) were independently associated with slope of renal decline. Conclusion: Achievement of less than 1.0 g/day proteinuria and MAP were important for limiting the loss of renal function, and relapse of proteinuria should be closely monitored in proteinuric IgA nephropathy.     

Significance of tonsillectomy combined with steroid pulse therapy for IgA nephropathy with mild proteinuria

Background

Medical intervention for patients with IgA nephropathy and mild proteinuria (<1.0 g/day) is controversial, and the effectiveness of tonsillectomy plus steroid pulse therapy (TSP) for such patients remains obscure.

Methods

Among 323 patients in our multicenter cohort study, 79 who had mild proteinuria (0.4–1.0 g/day) at diagnosis were eligible to participate in this study. We compared the clinicopathological findings at diagnosis, a decline in renal function defined as a 50 or 100 % increase in serum creatinine (sCr) and clinical remission (CR) defined as the disappearance of hematuria and proteinuria (<0.3 g/day) among groups given TSP (n = 46), steroid therapy (ST) (n = 9), and non-ST (n = 24). Factors contributing to CR were also evaluated using multivariate analysis.

Results

Background factors at diagnosis including age, ratio (%) of patients with hypertension, sCr, proteinuria, and histological severity did not significantly differ among the groups. Only two patients each in the TSP (4.3 %) and non-ST (8.3 %) groups achieved a 50 % increase in sCr during a mean follow–up period of 4.7 years. At the final observation, 71.7, 44.4, and 41.7 % of patients in the TSP, ST, and non-ST groups, respectively, achieved CR (p = 0.032). Cox proportional hazards models revealed that TSP led to CR more effectively than non-TSP by a factor of about threefold (hazard ratio, 2.74; p = 0.008).

Conclusion

TSP therapy has potential for inducing CR in patients with IgAN and mild proteinuria (<1.0 g/day).

     

Genetic effect of the NPHS2 gene variants on proteinuria in minimal change disease and immunoglobulin A nephropathy

Background: Proteinuria varies in different glomerular diseases and even the same one. Podocin, encoded by gene NPHS2, is important in maintaining the integrity of slit diaphragm structure and avoiding proteinuria. Presently, case–control association studies were performed to investigate the genetic effect of variants in NPHS2 in a mass proteinuric glomerulopathy, minimal change disease (MCD) at first, followed by further investigation in immunoglobulin A nephropathy (IgAN). Methods: At first, 214 northern Chinese patients with MCD and 493 geographically‐matched healthy controls were enrolled. Variants of the NPHS2 were screened. SNP‐2 (rs3829795:C>T, c.‐670C>T) and SNP‐5 (rs3738423:C>T, c.288C>T) were selected as tagging single nucleotide polymorphisms (SNP) and haplotypes were reconstructed. Association was analyzed in MCD patients. Then, the identified SNP site was analyzed in IgAN patients with mild histological changes (Haas subclass I and II). Results: The C allele and CC genotype frequencies at the SNP‐2 site, as well as the frequency of haplotype CC, were significantly lower in MCD patients than in healthy controls. Furthermore, they were also associated with the degree of proteinuria in MCD patients. But in IgAN patients, no such association was identified. Conclusion: The study suggested the polymorphism and haplotype of NPHS2 gene were associated with the genetic susceptibility and also the degree of proteinuria to MCD. Proteinuria in MCD and IgAN might occur through different mechanisms.     

Immunosuppressive treatments for immunoglobulin A nephropathy: a meta-analysis of randomized controlled trials

Immunoglobulin A (IgA) nephropathy is a worldwide disease that causes end-stage kidney disease (ESRD) in up to 15-20% of affected patients within 10 years from the apparent onset of disease and in up to 30-40% of individuals within 20 years from diagnosis. No specific treatment has been established and there is wide variation in current practice. This systematic review evaluates the use of immunosuppressive agents to treat patients with IgA nephropathy. The Cochrane Renal Group Specialized Register, Cochrane Controlled Trial Registry, MEDLINE, EMBASE and article reference lists were searched for randomized or quasi randomized trials. Two independent reviewers assessed studies for inclusion criteria (biopsy proven IgA nephropathy, randomized trial, use of immunosuppressive agents) and extracted data regarding the effects of immunosuppressive agents on ESRD, doubling of serum creatinine, glomerular filtration rate, urinary protein excretion and side-effects. Data were analysed with a random effects model. The published trials were few (13 trials, 623 patients) and were generally of poor quality. Compared with placebo, steroids were associated with a lower risk of progression to ESRD (six trials, 341 patients, RR 0.44, 95% CI 0.25-0.80) and lower end-of-trial proteinuria (six trials, 263 patients, weighted mean difference (WMD) -0.49 g/day, 95% CI -0.25 to -0.72). Treatment with alkylating agents significantly reduced end of treatment proteinuria (two trials, 122 patients, WMD -0.94, 95% CI -0.46 to -1.43). Although the optimal management of patients with IgA nephropathy remains uncertain because of limitations with the existing published data, immunosuppressive agents are a promising strategy and should be investigated further.     

Effect of aggregated immunoglobulin A1 from immunoglobulin A nephropathy patients on nephrin expression in podocytes

Aim: Abnormal immunoglobulin (Ig)A1 is considered to play a pivotal role in IgA nephropathy. We used mouse podocytes as the experimental model to investigate the effect of aggregated IgA1 (aIgA1) isolated from IgA nephropathy (IgAN) patients on nephrin expression in podocytes through direct and indirect pathways. Methods: Jacalin affinity chromatography and Sephacryl S‐200 molecular sieve chromatography were used to isolate IgA1 from blood of IgAN patients which was therefore became aIgA1. Podocytes were incubated with aIgA1 or special mesangial medium. Nephrin expression in podocytes was measured by real‐time polymerase chain reaction and western blot analysis. Results: Aggregated IgA1 from IgAN patients and healthy controls reduced nephrin expression in podocytes at mRNA and protein levels when compared with podocytes incubated with control medium (RPMI‐1640 with 0.5% foetal bovine serum) (P < 0.05). While medium from mesangial cells incubated with aIgA1 from IgAN inhibited nephrin expression in podocytes at mRNA and protein levels when compared with podocytes incubated with medium from mesangial cells with aIgA1 from healthy controls (P < 0.05). Conclusion: Our findings implicate that aIgA1 from IgAN patients could inhibit nephrin expression through direct and indirect pathways, although these mechanisms remain to be clarified.     

Aldosterone breakthrough during therapy with angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers in proteinuric patients with immunoglobulin A nephropathy

BACKGROUND: We are investigating whether aldosterone breakthrough negatively impacts on the antiproteinuric effects of angiotensin-converting enzyme (ACE) inhibitors and/or angiotensin II receptor blockers (ARB). METHODS: We examine the role of aldosterone breakthrough in 43 normotensive, proteinuric (0.7 +/- 0.3 g/day) outpatients (aged 41.5 +/- 10.9 years) with immunoglobulin A nephropathy (IgAN) accompanied by stable renal function (creatinine clearance >50 mL/min). The patients were treated with temocapril (1 mg; n = 14), losartan (12.5 mg; n = 16), or a combination therapy (n = 13) for 12 months. We prospectively evaluated blood pressure (BP), urinary protein excretion (UPE), biochemical parameters and the renin-angiotensin-aldosterone system before and after 12 months of treatment. RESULTS: Although the overall plasma aldosterone concentrations values did not change after any of the treatments administered for 12 months, they eventually increased in 23 (temocapril, seven patients; losartan, eight patients; combination, seven patients) of the 43 patients (53.4%; aldosterone breakthrough), and fell in the remainder (46.6%). Blood pressure and renal function did not differ among the three groups at 12 months. In contrast, UPE was significantly higher in patients with, than without aldosterone breakthrough during temocapril and losartan administration. However, combination therapy induced a more remarkable reduction in UPE regardless of aldosterone breakthrough. CONCLUSIONS: A combination of ACE inhibitors and ARB in normotensive patients with IgAN produces a more profound decrease in proteinuria than either monotherapy. This additive antiproteinuric effect is not dependent on aldosterone breakthrough. Additional larger, prospective, randomized studies will be needed for general acceptance of this strategy.     

Pathological sub-analysis of a multicenter randomized controlled trial of tonsillectomy combined with steroid pulse therapy versus steroid pulse monotherapy in patients with immunoglobulin A nephropathy

Background

The IgA nephropathy (IgAN) Study Group in Japan conducted a multicenter, randomized, controlled trial of tonsillectomy with steroid pulse therapy (TSP) versus steroid pulse monotherapy in patients with IgAN (UMIN Clinical Trial Registry Number; C000000384). The effects of therapies in relation to pathological severity were analyzed in this study.

Methods

The patients with IgAN, urinary protein 1.0–3.5 g/day, serum creatinine of 1.5 mg/dl or less were randomly assigned to receiving TSP (Group A) or steroid pulses alone (Group B). The primary endpoint was the disappearance of proteinuria and/or hematuria. Twenty-six biopsies in Group A and 33 in Group B were available. The histological grades (HG) according to the percentage of glomeruli with crescent or sclerosis and the Oxford classification were analyzed.

Results

The patients in Group A had a 4.32- to 12.1-fold greater benefit of disappearance of proteinuria and 3.61- to 8.17-fold greater benefit of clinical remission (disappearance of proteinuria and hematuria) than those in Group B in patients with HG2–3, acute lesions (cellular or fibrocellular crescent) affecting more than 5 % of glomeruli, chronic lesions (fibrous crescents or sclerosis) affecting more than 20 % and S1. In contrast, odds ratios for disappearance of proteinuria or clinical remission in Group A to Group B were not significant in patients with HG 1, acute lesion in 5 % or less of glomeruli, chronic lesion in 20 % or less and S0. The disappearance of hematuria showed no relation to pathological severity.

Conclusion

TSP might be better employed according to the pathological severity.

     

Comparison of effective impact among tonsillectomy alone, tonsillectomy combined with oral steroid and with steroid pulse therapy on long-term outcome of immunoglobulin A nephropathy

Background

To clarify the therapeutic impact of tonsillectomy and combined therapies of tonsillectomy plus steroid on the long-term prognosis of immunoglobulin A nephropathy (IgAN).

Methods

A retrospective study was conducted on 208 patients with IgAN between 1986 and 2009. According to the strategies for treatments, patients were divided into four groups: tonsillectomy and steroid pulse (TSP, n = 47), tonsillectomy and oral steroid (TOS, n = 33), tonsillectomy alone (T, n = 56), and N group (no particular therapy, n = 72). Multivariate analysis based on the Cox’s regression model was used to assess the relative risk of reaching the outcome of doubling creatinine based on the influence of baseline prognostic factors.

Results

The mean observation periods were 53.8 months in the TSP group, 122.0 months in the TOS group, 102.9 months in the T group, and 84.6 months in the N group. During an observation period, serum creatinine levels doubled as follows: one in the TSP group (2.1 %), two in the TOS group (6.1 %), five in the T group (8.9 %), histological severity, and 22 in the N group (30.6 %). The Cox’s regression proportional hazard model showed that gender, age, histological activity, dialysis induction risk and therapy were associated with doubling creatinine levels. Hazard ratios (95 % CI) and (P value) in T, TOS, and TSP groups versus N were 0.314 (0.11–0.93, P = 0.037), 0.213 (0.04–1.10, P = 0.065), and 0.032 (0.00–0.28, P = 0.002), respectively.

Conclusion

A combination therapy of tonsillectomy and steroid pulse had the most significant therapeutic impact compared to other therapies.     

Successful treatment with steroid and cyclosporine A in a patient with immunoglobulin A–proliferative glomerulonephritis with monoclonal immunoglobulin deposits

We report a case of glomerulonephritis with monoclonal immunoglobulin (Ig) A deposits as a form of monoclonal gammopathy of renal significance (MGRS) caused by monoclonal immunoglobulins without blood disorders in a 41‐year‐old woman. She developed lower leg oedema and was hospitalized because of nephrotic syndrome. Serum and urine were negative for M protein, and the free light chain κ/λ ratio was within the normal range. Renal histopathological findings included mesangial proliferation, endocapillary cell proliferation, and a double‐contour appearance of the capillary walls. Immunofluorescent staining indicated IgA and C3 deposits on the mesangium and capillary walls. Only λ chain and IgA1 deposits were noted. Fine granular sub‐endothelial deposits with no specific structure were observed under electron microscopy. The patient was diagnosed with IgA–proliferative glomerulonephritis with monoclonal immunoglobulin deposits (IgA‐PGNMID). The patient had decreased urine protein and sediment erythrocytes after she underwent two rounds of steroid pulse therapy and oral steroid therapy, but proteinuria and haematuria still remained. Four months later, the patient was administered 50 mg/day cyclosporine (CsA), and proteinuria and haematuria dramatically decreased. Only a few case reports have been published on IgA‐PGNMID. This case is rare in that the patient achieved successful treatment using a combination of steroids and CsA.     

Prednisolone-loaded liposome decreases the accumulation of glomerular extracellular matrix and glomerular injury of immunoglobulin A nephropathy in ddY mice

SUMMARY: Morphometric, immunofluorescent and electron microscopic analyses were performed to determine the glomerular changes of ddY mice after treatment with the prednisolone-loaded liposome (PSL-liposome) in the present study. A morphometric analysis including the extracellular matrix areas (ECMA), number of intraglomerular cell nuclei (NIGCN), and the ratio of glomerular tuft area (GTA) to the whole glomerular area (WGA) (GTA/WGA), or the ratio of glomerular Bowman's space (GBS) to GTA (GBS/GTA) was performed by image analysis using light microscopy. Extracellular matrix case, NIGCN and GTA/WGA of PSL-liposome-treated ddY mice were significantly decreased compared with those of ordinary prednisolone (PSL)-treated and saline control ddY mice. Glomerular Bowman's space/GTA was markedly increased in the PSL-liposome-treated ddY mice. the mean intensity of immunoglobulin (Ig)A, IgG, complement C3 or intercellular adhesion molecule-1 (ICAM-1) staining in glomeruli of the PSL-liposome treated ddY mice was also significantly decreased compared with those of ordinary PSL-treated and saline control ddY mice. Electron dense deposits in glomeruli were decreased after treatment with PSL-liposome in 61-week-old ddY mice. It appears that PSL-liposome therapy might reduce glomerular expansion, and intraglomerular cell proliferation and infiltration in IgA nephropathy of ddY mice.     

Characteristics of immunoglobulin A nephropathy with mesangial immunoglobulin G and immunoglobulin M deposition

Aim: There are immunoglobulin (Ig)A nephropathy (IgAN) cases showing mesangial IgG and/or IgM deposition, however, their characteristics have remained unknown. Methods: Three hundred and eighty‐four IgAN patients were divided according to the existence of mesangial IgG and/or IgM deposition: IgA deposition only (A group, n = 77); IgA and IgM deposition (AM group, n = 114); IgA and IgG deposition (AG group, n = 36); and IgA, IgG and IgM deposition (AGM group, n = 157). Clinical and histological findings, and outcomes were examined and compared among these four groups. Results: At the time of renal biopsy, serum creatinine was significantly higher in the A and AM group, however, creatinine clearance did not differ among the four groups. The ratio of glomerular obsolescence was significantly higher in the AM group than in the A and AGM group, and the ratio of glomerular tuft adhesion was significantly higher in the AM, AG and AGM group than in the A group. However, the other clinical and histological findings, electron microscopic findings and renal survivals did not differ among the four groups. Proteinuria was independently associated with an increase in risk of doubling of creatinine (P = 0.005), however, IgG and IgM depositions were not by multivariate Cox regression. Conclusion: The presence of other Ig classes, besides IgA deposits, was found to be associated with glomerular obsolescence and tuft adhesions, however, without any effect on renal survival in IgAN.     

Impact of tonsillectomy combined with steroid pulse therapy on immunoglobulin A nephropathy depending on histological classification: a multicenter study

Background

In addition to corticosteroids and inhibition of the renin–angiotensin–aldosterone system, tonsillectomy with steroid pulse therapy (TSP) may have a beneficial impact on the clinical course of IgA nephropathy (IgAN). However, there is still much uncertainty regarding the indications for therapy, treatment protocol, and therapeutic options for IgAN.

Methods

In this multicenter retrospective cohort study, we enrolled 284 patients with biopsy-proven IgAN who received TSP or corticosteroid therapy or conservative therapy. The effects of TSP on clinical remission (CR) were evaluated after a median follow-up period of 4.1 years in relation to histological classifications.

Results

Among the 284 participants, 161 patients received TSP. During the observation time, 141 patients (49.6 %) achieved CR, with a median time to remission of 397 days. In multivariate Cox regression analyses, TSP had an impact on achieving CR in only the group with histological grade 3 defined as glomerulosclerosis, crescent formation or adhesion to Bowman’s capsule in 10–30 % of all biopsied glomeruli, or mild cellular infiltration in the interstitium (hazard ratio (HR) 4.29, 95 % confidence interval (95 %CI) 1.88–11.19, P < 0.001). TSP independently contributed to a higher incidence of CR, particularly in the patient group showing evident mesangial hypercellularity (HR 2.54, 95 %CI 1.38–5.08, P = 0.002).

Conclusions

TSP may have a beneficial effect on the clinical course in IgAN patients with mild to moderate glomerular and interstitial lesions, particularly with distinct mesangial cell proliferation.

     

Spontaneous animal model, ddY mouse, for studying the pathogenesis and treatment in patients with immunoglobulin A nephropathy

Immunoglobulin (Ig)A nephropathy has the highest incidence among the various forms glomerulonephritis in the world. The initiating and progressive factors in patients with IgA nephropathy are still obscure. Although there is no specific treatment for patients with IgA nephropathy at present, more clinical trials of new treatments are warranted for such patients. Therefore, it is necessary to clarify those factors and to develop more effective drugs using a spontaneous animal model, the ddY mouse, in the future.     

Randomised controlled trial of leflunomide in the treatment of immunoglobulin A nephropathy

AIM: To investigate the effect of leflunomide for treatment of immunoglobulin A (IgA) nephropathy. METHODS: Sixty IgA nephropathy patients were divided into two groups at random. Patients in the test group received leflunomide and patients in the control group received fosinopril. Clinical data were obtained at weeks 2, 4, 6, 8, 12, 16, 20, 24 and 28. RESULTS: The complete remission rate was 62.1% and the total effectiveness rate was 72.4%. In the leflunomide group, proteinuria significantly decreased from 1.66 +/- 0.42 g to 0.60 +/- 0.68 g (P < 0.05). The efficacy rate of leflunomide compared with fosinopril in treating IgA nephropathy was not statistically different (P > 0.05). Side-effects were mild in both treatment groups. CONCLUSION: These preliminary results are encouraging, but further randomised studies are required before leflunomide can be recommended for the treatment of IgA nephropathy.     

Clinical remission and pathological progression after tonsillectomy in a renal transplant patient with recurrent IgA nephropathy

Abstract:  We discuss a renal transplant patient with recurrent IgA nephropathy (IgAN) before and after tonsillectomy. A 36-year-old man started on hemodialysis support in 1996 due to biopsy-proven IgAN, living related renal transplantation was then performed in 1997. Six years after transplantation, the patient presented with microhematuria and proteinuria. Graft biopsy for these urinary abnormalities showed recurrent IgAN. Tonsillectomy was subsequently performed in December 2003, proteinuria remitted 6 months after the tonsillectomy and microhematuria disappeared three years later. Protocol graft biopsy was subsequently performed twice, at 2 yr after the tonsillectomy (2005) and 4 yr after (2008). Comparing the findings of the pre-tonsillectomy biopsy and the two post-tonsillectomy biopsies, an increase in mesangial cells and matrix in 2005, and an expansion of the mesangial matrix and proliferation of mesangial interposition in 2008. In addition, global sclerosis of glomeruli increased over time, the area of tubulointerstitial damage has extended as well. While the tonsillectomy led to clinical remission of recurrent IgAN, the chronicity progressed on these protocol biopsies. This is the first report of the efficacy and the limitations of tonsillectomy in a case of recurrent IgAN in a transplant patient.     

Comparison of oral steroids with tonsillectomy plus steroid pulse therapy in patients with IgA nephropathy

Background

Treatment of IgA nephropathy (IgAN) in Japan has recently changed, from oral prednisolone (oPSL) to tonsillectomy plus steroid pulse (TSP) therapy. However, a few studies have compared their efficacy and safety.

Methods

IgAN patients diagnosed in our institution between 1991 and 2013, treated with TSP or oPSL, aged ≥16 years, with ≥1 g/day proteinuria, and estimated glomerular filtration rate (eGFR) ≥30 ml/min/1.73 m², and no other renal disease were selected. Baseline clinical and histological findings, clinical outcomes, and adverse events were compared. Clinical remission (CR) was defined as <0.3 g/day proteinuria and <5 urinary red blood cells per high-powered field.

Results

Sixty-six patients were identified; after propensity score adjustment, 26 patients were selected in each group. CR rates were significantly higher at 12 (30.8 % vs. 3.9 %), 36 (47.3 % vs. 7.9 %), and 72 (57.8 % vs. 20.1 %) months (p < 0.01), and the renal survival rate, defined as the development of a 25 % reduction from baseline eGFR, was significantly higher at 12 (96.2 % vs. 69.2 %), 36 (96.2 % vs. 61.5 %), and 72 (96.2 % vs. 41.0 %) months in the TSP than the oPSL group (p < 0.001). Multivariate analysis showed that TSP was the only independent factor associated with CR (hazard ratio, 3.58; 95 % confidence interval, 1.32–10.91, p = 0.01). The number of patients with adverse events was significant lower in TSP group than in oPSL group (11.5 % vs. 34.6 %, p = 0.04).

Conclusions

CR rates are higher; protection of renal function and prevention from adverse events were superior with TSP than with oPSL in patients with IgAN and moderate-to-severe proteinuria.