Cohort study of advanced IgA nephropathy: efficacy and limitations of corticosteroids with tonsillectomy

Current treatment status of IgA nephropathy in Japan: a questionnaire survey

BACKGROUND

In 2020, the Committee of Clinical Practical Guideline for IgA Nephropathy (IgAN) revised the clinical practice guidelines. Herein, we conducted a questionnaire survey to assess the potential discrepancies between clinical practice guidelines and real-world practice in Japan.

METHODS

A web-based survey of members of the Japanese Society of Nephrology was conducted between November 15 and December 28, 2021.

RESULTS

A total of 217 members (internal physicians: 203, pediatricians: 14) responded to the questionnaire. Of these respondents, 94.0% answered that the clinical practice guidelines were referred to "always" or "often." Approximately 66.4% respondents answered that histological grade (H-Grade) derived from the "Clinical Guidelines for IgA nephropathy in Japan, 3rd version" and the "Oxford classification" were used for pathological classification. Moreover, 73.7% respondents answered that the risk grade (R-grade) derived from the "Clinical Guidelines for IgA nephropathy in Japan, 3rd version" was referred to for risk stratification. The prescription rate of renin-angiotensin system blockers increased based on urinary protein levels (> 1.0 g/day: 88.6%, 0.5-1.0 g/day: 71.0%, < 0.5 g/day: 25.0%). Similarly, the prescription rate of corticosteroids increased according to proteinuria levels (> 1.0 g/day: 77.8%, 0.5-1.0 g/day: 52.8%, < 0.5 g/day: 11.9%). The respondents emphasized on hematuria when using corticosteroids. In cases of hematuria, the indication rate for corticosteroids was higher than in those without hematuria, even if the urinary protein level was 1 g/gCr or less. Few severe infectious diseases or serious deterioration in glycemic control were reported during corticosteroid use.

CONCLUSION

Our questionnaire survey revealed real-world aspects of IgAN treatment in Japan.

Associations of corticosteroid therapy and tonsillectomy with kidney survival in a multicenter prospective study for IgA nephropathy

Efficacy of systemic corticosteroid therapy (CS) for long-term kidney survival in patients with IgA nephropathy (IgAN) is controversial. Therefore, prospective studies evaluating targeted therapies to lymphatic tissues in mucosal immune system responsible for production of nephritogenic IgA have been desired worldwide. Here, we aimed to evaluate the associations of CS and combination therapy of CS and tonsillectomy (CS + Tx) with kidney survival, using database from a nationwide multicenter prospective cohort study on IgAN. Primary outcome was a 50% increase in serum creatinine from baseline or dialysis induction. The analysis included 941 patients (CS/CS + Tx/non-CS 239/364/338), 85 (9.0%) of whom reached outcomes during median follow-up of 5.5 (interquartile range 2.0-8.0) years. On overlap weighting analysis with balanced baseline characteristics, CS and CS + Tx were associated with lower risk of kidney events when compared with non-CS (hazard ratio [HR] 0.51, 95% confidence interval [CI] 0.29-0.88 and HR 0.20, 95%CI 0.09-0.44, respectively). Notably, when compared with the CS, CS + Tx was associated with a lower risk of kidney events (HR 0.40, 95%CI 0.18-0.91). Present study demonstrated, keeping with favorable association of systemic CS with kidney survival, concurrent tonsillectomy as one of targeted interventions to lymphatic tissues may provide additional improvement to kidney survival in patients with IgAN.

IgA Nephropathy: Pleiotropic impact of Epstein-Barr virus infection on immunopathogenesis and racial incidence of the disease

IgA nephropathy (IgAN) is an autoimmune disease in which poorly galactosylated IgA1 is the antigen recognized by naturally occurring anti-glycan antibodies, leading to formation of nephritogenic circulating immune complexes. Incidence of IgAN displays geographical and racial disparity: common in Europe, North America, Australia, and east Asia, uncommon in African Americans, many Asian and South American countries, Australian Aborigines, and rare in central Africa. In analyses of sera and cells from White IgAN patients, healthy controls, and African Americans, IgAN patients exhibited substantial enrichment for IgA-expressing B cells infected with Epstein-Barr virus (EBV), leading to enhanced production of poorly galactosylated IgA1. Disparities in incidence of IgAN may reflect a previously disregarded difference in the maturation of the IgA system as related to the timing of EBV infection. Compared with populations with higher incidences of IgAN, African Americans, African Blacks, and Australian Aborigines are more frequently infected with EBV during the first 1-2 years of life at the time of naturally occurring IgA deficiency when IgA cells are less numerous than in late childhood or adolescence. Therefore, in very young children EBV enters "non-IgA" cells. Ensuing immune responses prevent infection of IgA B cells during later exposure to EBV at older ages. Our data implicate EBV-infected cells as the source of poorly galactosylated IgA1 in circulating immune complexes and glomerular deposits in patients with IgAN. Thus, temporal differences in EBV primo-infection as related to naturally delayed maturation of the IgA system may contribute to geographic and racial variations in incidence of IgAN.

Efficacy and indications of tonsillectomy in patients with IgA nephropathy: a retrospective study

Background

The efficacy and indications of tonsillectomy in IgA nephropathy (IgAN) remain uncertain.

Methods

We performed a retrospective cohort study of 452 patients with primary IgAN, including 226 patients who received tonsillectomy and 226 controls selected by propensity score matching who had never undergone tonsillectomy. Study outcomes were clinical remission defined as negative hematuria and proteinuria on three consecutive visits over a 6-month period, the endpoint defined as end-stage renal disease or an irreversible 100% increase in serum creatinine from the baseline value. In addition, we further analyzed the critical level of proteinuria in the efficacy of tonsillectomy and the correlation between MEST-C score and tonsillectomy.

Results

Up to December 2019, the follow-up period lasted 46 ± 23 months (12-106 months). Kaplan-Meier and multivariate Cox regression analysis revealed that tonsillectomy was beneficial for clinical remission and renal survival. Whether proteinuria was ≤ 1 g/24h or >1 g/24h, the clinical remission and renal survival rates were greater in patients treated with tonsillectomy than without. When the pathological damage was mild or relatively severe, tonsillectomy may be beneficial to clinical remission or renal survival.

Conclusions

Tonsillectomy had a favorable effect on clinical remission and delayed renal deterioration in IgAN. In addition to patients with early stage IgAN, it may also be beneficial to IgAN patients with higher levels of proteinuria and relatively severe pathological damage.

Analysis of risk factors for post-tonsillectomy hemorrhage in adults

OBJECTIVES

To identify the risk factors for post-tonsillectomy hemorrhage (PTH) in adult patients (>19 years).

METHODS

275 adult patients who underwent tonsillectomy between 2009 and 2019 were retrospectively analyzed. Possible risk factors associated with PTH were investigated by univariate and multivariate logistic regression analyses.

RESULTS

PTH occurred in 39 of 275 patients (14.2%). Regarding underlying diseases, PTH occurred more frequently in focal infection of IgA nephropathy. Furthermore, bipolar electrocautery was the other risk factor for PTH on multivariate analysis.

CONCLUSION

Focal infection of IgA nephropathy and bipolar electrocautery were identified as the risk factors for PTH.

Tonsillectomy Combined With Steroid Pulse Therapy Prevents the Progression of Chronic Kidney Disease in Patients With Immunoglobulin A (IgA) Nephropathy in a Single Japanese Institution

Background Despite the abundant experience of tonsillectomy with steroid pulse therapy (TSP) for patients with immunoglobulin A (IgA) nephropathy, the therapeutic efficacy of TSP on renal prognosis remains controversial. The purpose of this study was to evaluate the efficacy of whether TSP effectively prevents chronic kidney disease (CKD) progression. Methods This was a single-center, retrospective observational study. A total of 149 patients were enrolled in the current study who were confirmed with IgA nephropathy by renal biopsy between February 2011 and August 2019. The impact of TSP on CKD progression was compared with conservative treatment during a follow-up period of 3 years. Results In total, 110 patients received TSP and 39 patients received conservative treatment. There were no differences between the two groups in the initial CKD stages: 65.1% of patients had CKD G1-2, 32.2% had CKD G3, and 2.7% had CKD G4-5. The initial urine protein was 0.7 g/gCr, which was not different between the two groups. Kaplan-Meier analysis showed that patients with TSP had a significantly better renal prognosis than those in the conservative treatment group after one and a half years (p = 0.007). Multivariable analysis revealed that TSP had a significant impact on the prevention of CKD progression, with an adjusted odds ratio of 0.07 (95% confidence interval, 0.01-0.87; p=0.039). However, we could not confirm the predictive value of the Oxford Classification on TSP efficacy. Additionally, the initial urinary protein level was a risk factor for CKD progression. Conclusions TSP was associated with a lower risk of CKD progression. In this regard, our study supports that TSP may be a reasonable treatment option for patients with IgA nephropathy. In the featured study, it needs to be elucidated which histopathological classifications benefit from TSP treatment.

Impact of the number of steroid pulses in tonsillectomy combined with steroid pulse therapy: a nationwide retrospective study in Japan

BACKGROUND

Steroid pulse therapy with tonsillectomy is known as a major treatment for IgA nephropathy (IgAN). However, its protocol was different among institutions and the effects of varying the number of steroid pulses remain unclear.

METHODS

From a total of 1,174 IgAN patients in a multicenter retrospective cohort analysis in Japan, 195 patients were treated by tonsillectomy combined with corticosteroid. They were divided into four groups based on the number of administered steroid pulses from 0 to three (TSP0-3), and remission of urinary abnormalities and renal survival until 1.5-fold increase in serum creatinine level from baseline were analyzed among the four groups and between TSP1 and TSP3.

RESULTS

Among the four groups, renal function was relatively good when the estimated glomerular filtration rate was approximately 80-90 mL/min/1.73m² and proteinuria was relatively mild (< 1.0 g/gCre). The ratio of patients who developed renal dysfunction was < 5% in all groups, and the cumulative renal survival rate by Kaplan-Meier analysis was similar among groups (log-rank test, p = 0.37), despite varying clinical backgrounds and treatments. After adjustment of the background variables between TSP1 and TSP3, the remission rates of urinary abnormalities were similar and the renal survival rate also remained similar (66.8 vs. 85.4%, p = 0.45).

CONCLUSIONS

In patients with mild proteinuria and good renal function, the number of steroid pulses did not affect the renal outcome in steroid pulse therapy with tonsillectomy. The adaptation and protocols, such as the number of steroid pulses, should be determined for each IgAN patient's background.

The impact of tonsillectomy combined with steroid pulse therapy in patients with advanced IgA nephropathy and impaired renal function

BACKGROUND

Preventing progression to end-stage renal disease (ESRD) in advanced IgA nephropathy (IgAN) patients with impaired renal function remains challenging. We analyzed the efficacy of tonsillectomy combined with steroid pulse therapy (TSP).

METHODS

In this retrospective analysis, IgAN patients with proteinuria > 0.5 g/day and estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m² were divided into three groups: patients treated with TSP (TSP group; n = 23), oral prednisolone (oPSL group; n = 41), and conservative therapy (CONS group, n = 51). We analyzed the clinical and histological backgrounds, remission of urinary findings, and renal survival rate to a 25% decline in eGFR from baseline, and incidence of ESRD.

RESULTS

There were significant differences in the patients' backgrounds among the groups. Therefore, we adjusted the background using propensity score marching between TSP group and oPSL or CONS group. The 5-year remission rate of hematuria was significantly higher in the TSP group than in the oPSL group, and that of both hematuria and proteinuria was significantly higher in the TSP group than in the CONS group. The 10-year renal survival rate was significantly higher in the TSP group than in the oPSL and CONS groups. In a multivariate Cox regression analysis, TSP was found to be an independent factor for the 25% decline in eGFR in entire cohort. The adverse effect frequency in the TSP group was similar to the CONS group.

CONCLUSIONS

TSP can effectively induce remission of urinary abnormality and improve the prognosis without frequent adverse effects in IgAN patients with impaired renal function.

Tonsillectomy plus steroid pulse therapy is the most effective treatment in adult patients with C-Grade I IgA nephropathy, and the weight of the extracted palatine tonsils and Yamamoto scale have no significant correlation with the effects of this treatment

OBJECTIVE

We studied patients who underwent tonsillectomy plus steroid pulse therapy (TSP) for immunoglobulin A nephropathy (IgAN), in order to investigate the clinical factors associated with a positive response to this treatment.

METHODS

We analyzed 118 IgAN patients who underwent TSP. We collected patients' data retrospectively, including age, sex, blood pressure, onset of IgAN, pathological findings of a renal biopsy, serum concentration of creatinine, estimated glomerular filtration rate, serum concentration of protein, urinary protein, hematuria, past history of tonsillitis, the Yamamoto scale, the weight and pathological findings of the extracted palatine tonsils, and the presence or absence of anti-platelet drugs and renin-angiotensin system inhibitors (RAS-I) usage. This study included participants who were over 18 years of age, had undergone tonsillectomy within three months of steroid pulse therapy administered thrice, in whom renal biopsy was performed within a year before treatment, and with follow-up period of over 3 years. Clinical remission (CR) of urinary abnormalities was defined as remission of both proteinuria and hematuria: three consecutive negative results over a 6-month period, with a urinary sediment red blood cell count of <5/HPF, and a proteinuria qualitative reaction of (-) to (±).

RESULTS

The CR rate of all cases was 56.8% and statistical significance was observed with respect to the C-Grade (P =  0.0003, P =  0.028) using both univariate and multivariate analysis. The CR rate of C-Grade І (73.4%) patients was significantly higher than that of C-Grade II patients (39.0%; P =  0.0004) and C-Grade III patients (30.8%; P =  0.003). We analyzed clinical factors in each C-Grade patient. No statistical significance was observed with respect to any of the factors using univariate analysis in C-Grade I patients. The weight of the extracted palatine tonsils and Yamamoto scale showed no statistical significance in every analysis. Fibrosis or hyalinization of the stroma of the palatine tonsils showed statistical significance (P =  0.026) only in the univariate analysis of C-Grade III patients. However, the patient number of C-Grade III was small.

CONCLUSION

Our results indicate that TSP is mostly effective in patients with of C-Grade I IgAN and that the C-Grade reflects the clinical indication for TSP. The weight of the extracted palatine tonsils and Yamamoto scale did not show obvious correlations with the clinical effect of TSP.

Influential factors on serum albumin concentration in hospitalized chronic kidney disease patients

BACKGROUND

Serum albumin concentration (SAC) is a prognostic factor that is affected by many factors such as postural change, liver function and food intake. Chronic kidney disease (CKD) patients excrete proteinuria, have low-protein diet, and receive glucocorticoid therapy. No one has evaluated the most influential factors on SAC in CKD patients.

METHODS

A retrospective study. Hospitalized CKD patients with less than 1 g/gCreatinine proteinuria receiving glucocorticoid therapy (n=28), with 1 or more g/gCreatinine proteinuria not receiving glucocorticoid therapy (n=36), and with 1 or more g/gCreatinine proteinuria receiving glucocorticoid therapy (n=39) were enrolled. SAC, hemoglobin, proteinuria and blood pressure at the last outpatient check-up before hospitalization, on the second day of hospitalization, at the last laboratory examination before discharge, as well as at the first outpatient follow-up after discharge were analyzed.

RESULTS

SAC decreased on the second day of hospitalization and increased at the first outpatient follow-up significantly in all groups. Unexpectedly, the change of SAC was irrelevant to the amount of proteinuria.

CONCLUSIONS

SAC was affected by not only proteinuria, but also postural change, physical activity, and food in CKD patients. SAC should be analyzed by standardizing a patient's condition during phlebotomy. J. Med. Invest. 64: 146-152, February, 2017.

Indications for tonsillectomy stratified by the level of evidence

Background: One of the most significant clinical trials, demonstrating the efficacy of tonsillectomy (TE) for recurrent throat infection in severely affected children, was published in 1984. This systematic review was undertaken to compile various indications for TE as suggested in the literature after 1984 and to stratify the papers according to the current concept of evidence-based medicine. Material and methods: A systematic Medline research was performed using the key word of "tonsillectomy" in combination with different filters such as "systematic reviews", "meta-analysis", "English", "German", and "from 1984/01/01 to 2015/05/31". Further research was performed in the Cochrane Database of Systematic Reviews, National Guideline Clearinghouse, Guidelines International Network and BMJ Clinical Evidence using the same key word. Finally, data from the "Trip Database" were researched for "tonsillectomy" and "indication" and "from: 1984 to: 2015" in combination with either "systematic review" or "meta-analysis" or "metaanalysis". Results: A total of 237 papers were retrieved but only 57 matched our inclusion criteria covering the following topics: peritonsillar abscess (3), guidelines (5), otitis media with effusion (5), psoriasis (3), PFAPA syndrome (6), evidence-based indications (5), renal diseases (7), sleep-related breathing disorders (11), and tonsillitis/pharyngitis (12), respectively. Conclusions: 1) The literature suggests, that TE is not indicated to treat otitis media with effusion. 2) It has been shown, that the PFAPA syndrome is self-limiting and responds well to steroid administration, at least in a considerable amount of children. The indication for TE therefore appears to be imbalanced but further research is required to clarify the value of surgery. 3) Abscesstonsillectomy as a routine is not justified and indicated only for cases not responding to other measures of treatment, evident complications, or with a significant history of tonsillitis. In particular, interval-tonsillectomy is not justified as a routine. 4) TE, with or without adenoidectomy, is efficacious to resolve sleep-related breathing disorders resulting from (adeno)tonsillar hypertrophy in children. However, the benefit is reduced by co-morbidities, such as obesity, and further research is required to identify prognostic factors for this subgroup of patients. Further research is indicated to clarify selection criteria not only for this subpopulation that may benefit from less invasive procedures such as tonsillotomy in the long-term. 5) Further trials are also indicated to evaluate the efficacy of TE on the clinical course in children with psoriasis guttata as well as on psoriasis vulgaris in adults, not responding to first-line therapy. 6) Conflicting results were reported concerning the role of TE in the concert to treat Ig-A nephropathy, mandating further clinical research. 7) Most importantly, randomized-controlled clinical trials with an adequate long-term follow-up are desirable to clarify the benefit of TE in patients with recurrent episodes of tonsillitis, with or without pharyngitis. Factors like age, spontaneous healing rate and postoperative quality of life have to be included when comparing TE with antibiotic therapy.

Why, when and how should immunosuppressive therapy considered in patients with immunoglobulin A nephropathy?

IgA nephropathy (IgAN) is the most common primary glomerulonephritis worldwide. Lifelong mesangial deposition of IgA1 complexes subsist inflammation and nephron loss, but the complex pathogenesis in detail remains unclear. In regard to the heterogeneous course, classical immunosuppressive and specific therapeutic regimens adapted to the loss of renal function will here be discussed in addition to the essential common renal supportive therapy. Renal supportive therapy alleviates secondary, surrogate effects or sequelae on renal function and proteinuria of high intraglomerular pressure and subsequent nephrosclerosis by inhibition of the renin angiotensin system (RAASB). In patients with physiological (ΔGFR < 1·5 ml/min/year) or mild (ΔGFR 1·5-5 ml/min/year) decrease of renal function and proteinuric forms (> 1 g/day after RAASB), corticosteroids have shown a reduction of proteinuria and might protect further loss of renal function. In patients with progressive loss of renal function (ΔGFR > 3 ml/min within 3 months) or a rapidly progressive course with or without crescents in renal biopsy, cyclophosphamide with high-dose corticosteroids as induction therapy and azathioprine maintenance has proved effective in one randomized controlled study of a homogeneous cohort in loss of renal function (ΔGFR). Mycophenolic acid provided further maintenance in non-randomized trials. Differentiated, precise, larger, randomized, placebo-controlled studies focused on the loss of renal function in the heterogeneous forms of IgAN are still lacking. Prospectively, fewer toxic agents will be necessary in the treatment of IgAN.

Long-term efficacy of tonsillectomy as a treatment in patients with IgA nephropathy: a meta-analysis

PURPOSE

IgA nephropathy (IgAN) is the most common glomerulonephritis worldwide and will lead some unfavorable outcomes such as end-stage renal disease. The efficacy of tonsillectomy remains controversial in both Asian and Caucasian ethnicity. Our meta-analysis was aiming at exploring its long-term efficacy and providing further evidences for clinical treatment.

METHODS

Prospective and retrospective studies that compared the rate of clinical remission and/or end-stage renal disease in IgAN patients who applied tonsillectomy were involved in our meta-analysis. The online databases we searched were PubMed, Embase, Cochrane Library, and Web of Science RESULTS: Nineteen studies with a total of 3483 participants are involved in our meta-analysis. It is found that treatment of tonsillectomy is significantly associated with a higher rate of clinical remission (15 studies, 3059 participants; pooled OR 3.30, 95 % CI 2.47-4.40). Meanwhile, tonsillectomy shows positive effect on refraining from developing end-stage renal disease (9 studies, 1804 participants; pooled OR 0.33, 95 % CI 0.16-0.69). In following two subgroup analyses, we integrate studies with more than 5 years of follow-up from clinical remission group and end-stage renal disease group. Both of them show that tonsillectomy has favorable long-term efficacy, pooled OR 3.37 (95 % CI 2.68-4.24) and 0.20 (95 % CI 0.12-0.33), respectively.

CONCLUSIONS

Long-term efficacy of tonsillectomy indicates that this treatment is helpful in inducing clinical remission and inhibiting development of end-stage renal disease in patients with IgAN and should be considered for addition into standard clinical treatment.

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.

The efficacy of tonsillectomy on clinical remission and relapse in patients with IgA nephropathy: a randomized controlled trial

BACKGROUND

The efficacy of tonsillectomy in immunoglobulin A nephropathy (IgAN) remains controversial. The aim of the study was to conduct a randomized controlled trial to evaluate the effect of tonsillectomy in patients with IgAN.

METHODS

We randomly selected 98 patients with biopsy-proven IgA nephropathy and randomly allocated to receive tonsillectomy combined with drug therapy (Group A) or drug therapy alone (Group B). The participating patients were entered into a 4-year single-center study. Remission and relapse rate were calculated for hematuria and proteinuria using the Kaplan-Meier method.

RESULTS

No differences were found between the two groups in their baseline clinical and histological characteristics. Patients with tonsillectomy exhibited considerable improvement in the following aspects compared to those patients who did not undergo tonsillectomy: time to reach first remission (3.1 vs. 24.9 months, p < 0.001) for hematuria and (2.5 vs. 26.1 months, p < 0.001) for proteinuria, cumulative remission rate (91.8% vs. 46.9%, p < 0.001 by log-rank test) for hematuria and (95.9% vs. 51.0%, p < 0.001) for proteinuria, the duration of first remission (26.5 vs. 11.8 months, p = 0.0047) for hematuria and (23.5 vs. 10.5 months, p = 0.0012) for proteinuria, as well as lower relapse rate for hematuria and proteinuria in Group A.

CONCLUSION

Our clinical data demonstrated that tonsillectomy could be beneficial for IgAN patients, particularly by contributing to faster and longer remission, as well as reducing the frequency of possible future relapses.

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).

New Insights into the Pathogenesis of IgA Nephropathy

BACKGROUND

IgA nephropathy, a frequent cause of end-stage renal disease, is an autoimmune disease wherein immune complexes consisting of IgA1 with galactose-deficient O-glycans (autoantigen) and anti-glycan autoantibodies deposit in glomeruli and induce renal injury. Multiple genetic loci associated with disease risk have been identified. The prevalence of risk alleles varies geographically, highest in eastern Asia and northern Europe, fewer in other parts of Europe and North America, and the least in Africa. IgA nephropathy is diagnosed from pathological assessment of a renal biopsy specimen. Currently, therapy is not disease-targeted but rather is focused on maintaining control of blood pressure and proteinuria, ideally with suppression of angiotensin II. Possible additional approaches differ between countries. Disease-specific therapy as well as new tools for diagnosis, prognosis, and assessment of responses to therapy are needed.

SUMMARY

Glycosylation pathways associated with aberrant O-glycosylation of IgA1 and, thus, production of autoantigen, have been identified. Furthermore, unique characteristics of the autoantibodies in IgA nephropathy have been uncovered. Many of these biochemical features are shared by patients with IgA nephropathy and Henoch-Schönlein purpura nephritis, suggesting that the two diseases may represent opposite ends of a spectrum of a disease process. Understanding the molecular mechanisms involved in formation of pathogenic IgA1-containing immune complexes will enable development of disease-specific therapies as well as diagnostic and prognostic biomarkers.

KEY MESSAGES

IgA nephropathy is an autoimmune disease caused by glomerular deposition of nephritogenic circulating immune complexes consisting of galactose-deficient IgA1 (autoantigen) bound by anti-glycan autoantibodies. A better understanding of the multi-step process of pathogenesis of IgA nephropathy and the genetic and environmental contributing factors will lead to development of biomarkers to identify patients with progressive disease who would benefit from a future disease-specific therapy.

Tonsillectomy for IgA nephropathy: a meta-analysis

BACKGROUND

The efficacy of tonsillectomy in immunoglobulin A nephropathy (IgAN) remains controversial. Our meta-analysis was intended to investigate its efficacy as an adjunct or independent treatment.

STUDY DESIGN

Meta-analysis of prospective and retrospective studies using PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials.

SETTING & POPULATION

Patients with IgAN treated with or without tonsillectomy.

SELECTION CRITERIA FOR STUDIES

Studies that compared clinical remission or end-stage renal disease (ESRD) in patients with IgAN with or without tonsillectomy.

INTERVENTION

Tonsillectomy.

OUTCOMES

Clinical remission and ESRD.

RESULTS

14 studies (1,794 patients) were included and a random-effects model was applied. There were significantly greater odds of clinical remission with tonsillectomy (10 studies, 1,431 patients; pooled OR, 3.40; 95% CI, 2.58-4.48; P<0.001). Sensitivity analysis to exclude the effects of renin-angiotensin system inhibitors yielded consistent results (6 studies, 671 patients; pooled OR for remission, 2.80; 95% CI, 1.91-4.09; P<0.001). In subgroup analysis of the remission outcome, tonsillectomy plus steroid pulse therapy was superior to steroid pulse therapy alone (7 studies, 783 patients; pooled OR, 3.15; 95% CI, 1.99-5.01; P<0.001), and tonsillectomy plus conventional steroid therapy was superior to conventional steroid therapy alone (2 studies, 159 patients; pooled OR, 4.13; 95% CI, 1.23-13.94; P=0.02). Tonsillectomy was superior to general treatment (3 studies, 187 patients; pooled OR for remission, 2.21; 95% CI, 1.20-4.05; P=0.01). In addition, tonsillectomy was associated with decreased odds of ESRD (9 studies, 873 patients; pooled OR, 0.25; 95% CI, 0.12-0.52; P<0.001). 2 sensitivity analyses, one excluding studies with less than 5 years' follow-up and another excluding the confounding effect of renin-angiotensin system inhibitors, yielded nearly the same reduction in ESRD risk (6 studies, 691 patients; pooled OR, 0.20; 95% CI, 0.11-0.36; P<0.001; and 6 studies, 547 patients; pooled OR, 0.24; 95% CI, 0.14-0.44; P<0.001).

LIMITATIONS

Most included studies were retrospective cohort studies; we were unable to adjust uniformly for potential confounding variables.

CONCLUSIONS

As adjunct or independent therapy, tonsillectomy may induce clinical remission and reduce the rates of ESRD in patients with IgAN.

Effect of tonsillectomy and its timing on renal outcomes in Caucasian IgA nephropathy patients

PURPOSE

The role of tonsillectomy in the treatment of IgA nephropathy in Caucasian patients is controversial.

METHODS

A retrospective cohort study was conducted in 264 patients with biopsy-proven primary IgA nephropathy to examine the association between tonsillectomy and long-term renal survival, defined as the incidence of estimated glomerular filtration rates (eGFRs) of ≤30 ml/min/1.73 m(2) or end-stage renal disease (the composite of initiation of dialysis treatment or renal transplantation). The association of tonsillectomy with renal end-points was examined using the Kaplan-Meier method and Cox models.

RESULTS

One-hundred and sixty-six patients did not undergo tonsillectomy (Group I, follow-up 130 ± 101 months) and 98 patients underwent tonsillectomy (Group II, follow-up 170 ± 124 months). The mean renal survival time was significantly longer for both end-points between those patients who underwent tonsillectomy (Group II) versus patients without tonsillectomy (Group I) (p < 0.001 and p = 0.005). The mean renal survival time was significantly longer for both end-points between those patients who had macrohaematuric episodes versus patients who had no macrohaematuric episodes (p = 0.035 and p = 0.019). Tonsillectomy, baseline eGFR and 24-h proteinuria were independent risk factors for both renal end-points.

CONCLUSION

Tonsillectomy may delay the progression of IgA nephropathy mainly in IgA nephropathy patients with macrohaematuria. Prospective investigation of the protective role of tonsillectomy in Caucasian patients is needed.

Outcome of tonsillectomy for recurrent IgA nephropathy after kidney transplantation

Since 2007, we have performed tonsillectomies for patients with recurrent immunoglobulin A nephropathy (IgAN) after kidney transplantation. Seven patients with primary IgAN showed biopsy-proven recurrent IgAN after living-donor kidney transplantation. They had persistent proteinuria or hematuria for an average of 40.3 months, and tonsillectomy was performed, on average, 75.6 months after kidney transplantation. In six patients with observation periods of more than one year, good remission of urinary findings was observed after tonsillectomy. We classified the seven patients into three types of renal injury based on histological findings: severe, moderate, and mild. Two patients classified with severe renal injury at the time of tonsillectomy had other problems, such as refractory hypertension and bilateral sinusitis. They followed a rapidly progressive clinical course. One case already had moderate histological renal injury. He demonstrated prompt amelioration of urinary findings after tonsillectomy but immediate deviation from remission of proteinuria and hematuria. In the four cases presenting mild renal injury at tonsillectomy, the improved urinary findings and serum creatinine value after tonsillectomy have persisted. In conclusion, tonsillectomy may be a favorable treatment for cases of mild-grade IgAN. However, other treatments such as antihypertensive agents and diet therapy may be necessary in other grades.

A case of immunoglobulin A nephropathy treated successfully with tonsillectomy and steroid pulse therapy 20 years after onset

A 46-year-old male was found to have proteinuria on a routine medical examination in 1985 at the age of 22 years and was diagnosed with immunoglobulin A (IgA) nephropathy by renal biopsy. He regularly visited a hospital, but 3 years later made the decision to stop. In 2000, his serum creatinine level was 1.3 mg/dl. His renal function then deteriorated, with persistent proteinuria and hematuria, following which he visited our hospital in December 2008. A further renal biopsy was performed. Active and chronic IgA nephropathy was confirmed histologically, with sclerosing lesions also being found. He was treated with three courses of steroid pulse therapy in February and tonsillectomy in April 2009. During the follow-up period at the outpatient clinic, results for proteinuria and hematuria were negative, suggesting that progression of renal impairment had been prevented. The efficacy of tonsillectomy plus steroid pulse therapy for early IgA nephropathy has been demonstrated, and this treatment was effective in our patient 20 years after the onset of the disease.

Uncoupling of glomerular IgA deposition and disease progression in alymphoplasia mice with IgA nephropathy

Previous clinical and experimental studies have indicated that cells responsible for IgA nephropathy (IgAN), at least in part, are localized in bone marrow (BM). Indeed, we have demonstrated that murine IgAN can be experimentally reconstituted by bone marrow transplantation (BMT) from IgAN prone mice in not only normal mice, but also in alymphoplasia mice (aly/aly) independent of IgA⁺ cells homing to mucosa or secondary lymphoid tissues. The objective of the present study was to further assess whether secondary lymph nodes (LN) contribute to the progression of this disease. BM cells from the several lines of IgAN prone mice were transplanted into aly/aly and wild-type mice (B6). Although the transplanted aly/aly showed the same degree of mesangial IgA and IgG deposition and the same serum elevation levels of IgA and IgA-IgG immune-complexes (IC) as B6, even in extent, the progression of glomerular injury was observed only in B6. This uncoupling in aly/aly was associated with a lack of CD4⁺ T cells and macrophage infiltration, although phlogogenic capacity to nephritogenic IC of renal resident cells was identical between both recipients. It is suggested that secondary LN may be required for the full progression of IgAN after nephritogenic IgA and IgA/IgG IC deposition.

A multicenter randomized controlled trial of tonsillectomy combined with steroid pulse therapy in patients with immunoglobulin A nephropathy

Background

The study aim was, for the first time, to conduct a multicenter randomized controlled trial to evaluate the effect of tonsillectomy in patients with IgA nephropathy (IgAN).

Methods

Patients with biopsy-proven IgAN, proteinuria and low serum creatinine were randomly allocated to receive tonsillectomy combined with steroid pulses (Group A; n = 33) or steroid pulses alone (Group B; n = 39). The primary end points were urinary protein excretion and the disappearance of proteinuria and/or hematuria.

Results

During 12 months from baseline, the percentage decrease in urinary protein excretion was significantly larger in Group A than that in Group B (P < 0.05). However, the frequency of the disappearance of proteinuria, hematuria, or both (clinical remission) at 12 months was not statistically different between the groups. Logistic regression analyses revealed the assigned treatment was a significant, independent factor contributing to the disappearance of proteinuria (odds ratio 2.98, 95% CI 1.01–8.83, P = 0.049), but did not identify an independent factor in achieving the disappearance of hematuria or clinical remission.

Conclusions

The results indicate tonsillectomy combined with steroid pulse therapy has no beneficial effect over steroid pulses alone to attenuate hematuria and to increase the incidence of clinical remission. Although the antiproteinuric effect was significantly greater in combined therapy, the difference was marginal, and its impact on the renal functional outcome remains to be clarified.

Changes in nephritogenic serum galactose-deficient IgA1 in IgA nephropathy following tonsillectomy and steroid therapy

Background

Recent studies have shown that galactose-deficient IgA1 (GdIgA1) has an important role in the pathogenesis of IgA nephropathy (IgAN). Although emerging data suggest that serum GdIgA1 can be a useful non-invasive IgAN biomarker, the localization of nephritogenic GdIgA1-producing B cells remains unclear. Recent clinical and experimental studies indicate that immune activation tonsillar toll-like receptor (TLR) 9 may be involved in the pathogenesis of IgAN. Here we assessed the possibility of GdIgA1 production in the palatine tonsils in IgAN patients.

Methods

We assessed changes in serum GdIgA1 levels in IgAN patients with clinical remission of hematuria and proteinuria following combined tonsillectomy and steroid pulse therapy. Further, the association between clinical outcome and tonsillar TLR9 expression was evaluated.

Results

Patients (n = 37) were divided into two groups according to therapy response. In one group, serum GdIgA1 levels decreased after tonsillectomy (59%) alone, whereas in the other group most levels only decreased after the addition of steroid pulse therapy to tonsillectomy (41%). The former group showed significantly higher tonsillar TLR9 expression and better improvement in hematuria immediately after tonsillectomy than the latter group.

Conclusions

The present study indicates that the palatine tonsils are probably a major sites of GdIgA1-producing cells. However, in some patients these cells may propagate to other lymphoid organs, which may partially explain the different responses observed to tonsillectomy alone. These findings help to clarify some of the clinical observations in the management of IgAN, and may highlight future directions for research.

Nationwide survey on current treatments for IgA nephropathy in Japan

BACKGROUND

A wide variety of treatments, including tonsillectomy and steroid pulse therapy (TSP), are performed for the various stages of IgA nephropathy (IgAN) in Japan. However, the current status of treatments for IgAN patients in Japan is still unclear. The objective of the present study was to investigate the current status of treatments for IgAN patients.

METHODS

A nationwide survey was conducted in 2008 by sending questionnaires to the 1,194 teaching hospitals of the Japanese Society of Nephrology (JSN) via Progressive Renal Diseases Research, Research on intractable disease, from the Ministry of Health, Labour and Welfare of Japan.

RESULTS

Among the total 376 hospitals (31.4 %) that responded, 188 hospitals (66.2 % in the internal medicine departments) performed TSP, out of which 137 hospitals (61.4 %) had begun to perform TSP in the period from 2004 to 2008. The following two major steroid pulse protocols in TSP were used: (1) three cycles over 3 consecutive weeks and (2) three cycles every 2 months. Approximately 68 % of pediatric hospitals (68 hospitals) performed combination therapy with prednisolone, azathioprine, heparin-warfarin and dipyridamole. The clinical remission rates for hematuria and proteinuria after TSP tended to be higher than those following other corticosteroid therapies. Almost all hospitals prescribed antiplatelet agents and renin angiotensin system inhibitor (RAS-I).

CONCLUSION

In addition to popular treatments such as antiplatelet agents and RAS-I, TSP is becoming a standard treatment for adult IgAN patients in Japan.

Evaluation of tonsillectomy before kidney transplantation in patients with IgA nephropathy

The effectiveness of a tonsillectomy before kidney transplantation (KTx) in suppressing the recurrence of IgA nephropathy (IgAN) has never been studied. The aim of this study was to analyze the effectiveness of a preoperative tonsillectomy for preventing IgAN recurrence and to identify predictive risk factors for IgAN recurrence. Of the 462 recipients who underwent a KTx between 2006 and 2011, a total of 78 patients had biopsy-proven IgAN as their primary disease. Among these 78 patients, 28 patients (group 1) underwent a tonsillectomy and 50 patients (group 2) did not undergo a tonsillectomy before KTx. The time to recurrence was 15.5±8.7months, in group 1 and 20.2±18.6months in group 2. No significant difference was observed between the two groups (P=0.63). Using a multivariate Cox regression analysis, ABO incompatible KTx and acute rejection were associated with a lower incidence of recurrence (P=0.02 and 0.002 respectively). These results suggested that a preoperative tonsillectomy might not affect the recurrence of IgAN during a short-term follow-up period, whereas preoperative desensitization and the use of a higher steroid dose were effective for suppressing the recurrence of IgAN.

Comparison between consecutive and intermittent steroid pulse therapy combined with tonsillectomy for clinical remission of IgA nephropathy

BACKGROUND

In recent years, tonsillectomy and steroid pulse (TSP) therapy have been widely performed in Japan. However, there is no consensus about the treatment protocol and indication.

METHODS

In this retrospective analysis, we compared patients who received tonsillectomy plus intermittent steroid pulse (SP) therapy three times in 6 months (ISP group, n = 44) with patients who received tonsillectomy plus 3 weeks of consecutive SP therapy (CSP group, n = 46) within 1 year after renal biopsy. These two different protocols were performed at two different institutions. We analyzed the clinical and histological background and clinical remission (CR), defined as disappearance of urine abnormalities at 18 months after starting treatment.

RESULTS

Before treatment, there was no significant difference in the clinical findings except for sex between the two groups. In ISP group and CSP group, mean estimated glomerular filtration rate was 82.1 ± 20.9 and 85.9 ± 19.1 ml/min/1.73 m(2), median proteinuria was 0.55 and 0.56 g/day, and median urinary red blood cells were 20 (10-20) and 20 (6-30)/high power filed. The histological (H) grade was lower in the CSP than the ISP group (p = 0.022). The remission rate of proteinuria, hematuria, and rate of CR by the Kaplan-Meier method and logrank test were significantly higher in the CSP group than in the ISP group (CSP vs. ISP group; proteinuria: 97.8 vs. 77.3 %, p < 0.001, hematuria: 97.8 vs. 75.0 %, p = 0.005, CR: 95.6 vs. 63.6 %, p < 0.001). In the Cox proportional hazard model (forced entry), SP protocol and proteinuria before treatment were significantly associated with CR [SP protocol: hazard ratio (HR) 2.50, 95 % confidence interval (CI) 1.46-4.30, p = 0.001, proteinuria: HR 0.81, 95 % CI 0.68-0.96, p = 0.013)]. However H-grade was associated with remission of proteinuria (H-grade: hazard ratio (HR) 0.56, 95 % confidence interval (CI) 0.37-0.85, p = 0.006), and this result meant histological bias affected the remission of proteinuria.

CONCLUSIONS

The difference of the protocol of TSP therapy may have some effect on the CR of IgAN, though the histological bias was observed in this study. The appropriate protocol and indication of TSP therapy must be analyzed and determined in the randomized controlled trial.

Advanced IgA nephropathy with impaired renal function benefits from losartan treatment in rats

BACKGROUND

Treatment with angiotensin receptor blockers (ARBs) is successful in mitigating IgA nephropathy (IgAN), independent of blood pressure changes, but the therapeutic role of ARB in advanced IgAN with impaired renal function is to be ascertained. The present study was performed to investigate the effect of losartan on advanced IgAN induced by staphylococcal enterotoxin B (SEB) combined with 5/6 nephrectomy in rats.

METHODS

Fifty-four male SD rats were randomly divided into three group: Rats in the model group were treated with SEB plus 5/6 nephrectomy, and those in the losartan group were gavaged with losartan (33.3 mg kg(-1 )d(-1)) besides the treatment with SEB plus 5/6 nephrectomy. The urine and blood biochemical changes of rats were tested. IgA, IgG, IgM and C3 depositions were studied dynamically with immunofluorescence. The renal tissue structures were observed under light microscopy. The expressions of TGF-β1, FN, alpha-SMA and FGF-1 in rat renal tissues were determined with immunohistochemical methods and real-time PCR.

RESULTS

At 12 weeks, rats with SEB treatment plus 5/6 nephrectomy showed gradually increased urinary red blood cell (URBC) with a gradual elevation of the 24 h urinary protein, serum BUN and Scr, but losartan treatment lowered the levels of 24 h urinary protein, serum BUN and Scr. A large number of IgA depositions in the mesangial area, glomerulosclerosis and tubulointerstitial fibrosis were found in the model group, and the losartan group showed relieved injury. The expressions of TGF-β1, FN, alpha-SMA and FGF-1 were significantly elevated in the model. Losartan lessened their expressions.

CONCLUSION

Losartan treatment can delay the progression of advanced IgA nephropathy with impaired renal function.

The complex of immunoglobulin A and uromodulin as a diagnostic marker for immunoglobulin A nephropathy

Background

The only tool to diagnose immunoglobulinn A nephropathy (IgAN) is renal biopsy which requires hospitalization; moreover, renal biopsy has a risk of critical bleeding. Therefore, a non-invasive method for accurate diagnosis of IgAN is desirable and a must-to-have tool for the clinics. For this purpose, we evaluated the diagnostic value of the IgA–uromodulin complex in the urine of patients with IgAN for its feasibility and adequacy.

Method

We determined the IgA–uromodulin complex as a candidate for a diagnostic marker of IgAN by immunoprecipitation, liquid chromatography−mass spectrometry (LC–MS) and Western blot analysis. The enzyme-linked immunosorbent assay (ELISA) for the IgA–uromodulin complex was developed and applied to urine samples obtained from various kidney disease patients.

Result

One hundred and three of 126 urine samples (81.7%) from IgAN patients were positive for the IgA–uromodulin complex, while only 25 out of 94 urine samples (26.6%) in other kidney disease patients were positive. Sensitivity was 81.7%, specificity was 73.4%, and diagnosis efficiency was 78.2%. The complex was negative in eight urine samples obtained from patients with Alport syndrome which is almost impossible to discriminate from IgAN by routine urinalysis.

Conclusion

Detection of the urinary IgA–uromodulin complex by ELISA is a useful non-invasive method to diagnose IgAN.

A treatment dilemma in adult immunoglobulin A nephropathy: what is the appropriate target, preservation of kidney function or induction of clinical remission?

Immunoglobulin (Ig) A nephropathy is the most common type of glomerulonephritis worldwide. Data on its natural history suggest that approximately 40% of patients progress to end-stage renal failure after 20 years. Various therapies such as antiplatelet medication, fish oil, oral prednisolone, intravenous prednisolone, tonsillectomy, and tonsillectomy plus steroid pulse (TSP) have been proposed. Japanese nephrologists face challenging issues regarding this disease, such as the usefulness of the annual urinary screening system (kenshin) and kidney biopsies, the desire of patients and their families for treatment despite insufficient clinical evidence, and the risk of overtreatment with TSP versus the loss of a ‘golden period’ with late intervention. We review the current literature on tonsillectomy, steroid therapy, and TSP, which was first proposed in Japan, and present some perspectives on the treatment of IgA nephropathy.

Current therapy for IgA nephropathy

IgA nephropathy (IgAN) is a very common glomerulonephritis worldwide. In this review, we discuss therapeutic options in four clinical scenarios encountered in patients with IgAN: first is the patient with minor urinary abnormalities where the mainstay of treatment is long-term, regular follow-up to detect renal progression and hypertension. Second is the typical patient presenting with microhematuria, significant but non-nephrotic proteinuria, hypertension, and variable degrees of renal failure. Here the mainstay of treatment is optimized supportive care. If this does not lower proteinuria below 1 g/d, corticosteroid monotherapy may be effective, as long as the GFR is above 50 ml/min. There is insufficient data to advocate the use of other immunosuppressive drugs or even combination therapy in such patients. Third is the atypical patient with overt nephrotic syndrome, or acute or rapidly progressive kidney injury where a possible vasculitic form of IgAN should be sought and, if present, treated with immunosuppression. In other atypical patients with secondary IgAN, treatment should target the underlying primary disease. And fourth is the transplanted patient with recurrent IgAN where the mainstay of treatment is optimized supportive care.

Comparison of steroids and angiotensin receptor blockers for patients with advanced IgA nephropathy and impaired renal function

BACKGROUND/AIMS

The therapeutic strategy for advanced IgA nephropathy patients with impaired renal function is still controversial.

PATIENTS AND METHODS

We divided 44 IgA nephropathy patients with an estimated glomerular filtration rate (eGFR) of less than 60 ml/min/1.76 m(2) and proteinuria greater than 0.5 g/g · creatinine into two groups: the angiotensin receptor blocker (ARB) group (n = 22), treated with ARBs, and the steroid group (n = 22), treated with corticosteroid. We analyzed the clinical and histological background, renal survival rate until progression to end-stage renal disease (ESRD), and the risk factors for progression.

RESULTS

The clinical and histological backgrounds were not significantly different between the groups. At 1 and 2 years after treatment, proteinuria tended to be decreased from baseline in both groups, but not significantly, and urinary red blood cells were significantly decreased in the steroid groups (p < 0.001), but not in the ARB group. The eGFR tended to be increased in the steroid group and decreased in the ARB group. However, the renal survival rate until ESRD was not significantly different between the groups. There were no significant independent risk factors for progression.

CONCLUSION

The beneficial effect of ARBs on renal survival of advanced IgA nephropathy with impaired renal function is equal to that with steroids.

Tonsillar TLR9 expression and efficacy of tonsillectomy with steroid pulse therapy in IgA nephropathy patients

BACKGROUND

Patients with IgA nephropathy (IgAN) often show aggravation of renal injury with macroscopic hematuria after mucosal infections, especially tonsillitis. We previously demonstrated the important role of mucosal Toll-like receptor 9 (TLR9) activation in the pathogenesis of murine IgAN. Moreover, a single nucleotide polymorphism (SNP) in TLR9 was significantly associated with pathological severity in human IgAN. In this study, we investigated correlations between tonsillar TLR9 messenger RNA expression, TLR9 SNP genotypes and clinical outcomes following tonsillectomy with steroid pulse therapy (SPT) in IgAN patients.

METHODS

Tonsillar TLR9 expression was examined in IgAN (n = 49) and control (n = 15) patients who had undergone tonsillectomy. The correlations between tonsillar TLR9 expression level, TLR9 SNP genotypes and clinical outcomes after tonsillectomy with SPT were examined.

RESULTS

High expression of tonsillar TLR9 was observed in ∼23% of IgAN patients. These patients showed stronger and earlier remission of hematuria and proteinuria than those with low TLR9 expression. Patients with the TT genotype of TLR9 SNP (rs352140) had more severe renal damage than those with other genotypes. Patients whose serum IgA level decreased more than average after tonsillectomy (large ΔIgA) showed higher cumulative remission rates of proteinuria than patients with a smaller decrease in these levels (small ΔIgA). CT/CC genotypes were more dominant and tonsillar TLR9 expressions significantly higher in large ΔIgA patients than in small ΔIgA patients.

CONCLUSION

In IgAN patients, expression levels of tonsillar TLR9 and TLR9 SNP were well correlated with the efficacy of tonsillectomy with SPT.

Pathological role of tonsillar B cells in IgA nephropathy

Although impaired immune regulation along the mucosa-bone marrow axis has been postulated to play an important role, the pathogenesis of IgA nephropathy (IgAN) is unknown; thus, no disease-specific therapy for this disease exists. The therapeutic efficacy of tonsillectomy or tonsillectomy in combination with steroid pulse therapy for IgAN has been discussed. Although randomized control trials for these therapies are ongoing in Japan, the scientific rationale for these therapies remains obscure. It is now widely accepted that abnormally glycosylated IgA1 and its related immune complex (IC) are probably key molecules for the pathogenesis, and are thus considered possible noninvasive biomarkers for this disease. Emerging evidence indicates that B cells in mucosal infections, particularly in tonsillitis, may produce the nephritogenic IgA. In this paper, we briefly summarize characteristics of the nephritogenic IgA/IgA IC, responsible B cells, and underlying mechanisms. This clinical and experimental information may provide important clues for a therapeutic rationale.

A meta-analysis of the clinical remission rate and long-term efficacy of tonsillectomy in patients with IgA nephropathy

BACKGROUND

We wished to evaluate the clinical remission rate and long-term efficacy of tonsillectomy for patients with IgA nephropathy.

METHODS

We searched a number of databases, including PubMed, CNKI, Wanfang and others, for clinical case-control studies of tonsillectomy in patients with IgA nephropathy. We then performed a meta-analysis of these studies. After evaluating total clinical remission rates, we compared the remission rates for specific treatments: tonsillectomy plus steroid pulse, tonsillectomy plus normal-dose steroid, and general treatment using neither tonsillectomy nor steroids. We also compared the rates of end-stage renal failure (ESRF) at last follow-up to estimate the long-term renal survival rate associated with each treatment.

RESULTS

Seven retrospective studies met the inclusion criteria and were included. These included a total of 858 patients, in which 534 underwent tonsillectomy and 324 did not. The total clinical remission rate was higher in the operative group, while the ESRF rate was higher in the non-operative group. The clinical remission rate in patients who underwent tonsillectomy remained higher than in the non-operative group at both 5- and 10-year follow-up. The clinical remission rate in patients who underwent tonsillectomy plus steroid pulse was higher than in those treated with steroid pulse alone, normal-dose steroids or general treatment alone (P < 0.05). However, the clinical remission rate of simple tonsillectomy was not higher than that of general treatment (P > 0.05).

CONCLUSIONS

Whereas neither tonsillectomy nor steroid treatment alone increased remission rates in patients with IgA nephropathy, tonsillectomy combined with either normal steroid or steroid pulse treatment resulted in higher remission rates with favourable long-term efficacy.

Proteinuria-reducing effects of tonsillectomy alone in IgA nephropathy recurring after kidney transplantation

BACKGROUND

Few studies have been conducted to determine the efficacy of tonsillectomy in suppressing IgA nephropathy recurring after the kidney transplantation.

MATERIALS AND METHODS

Of the 405 kidney recipients who received allograft transplants at our institution between 1998 and 2005, 63 (63 of 405, 16%) were diagnosed as having recurrence of IgA nephropathy in the kidney graft. Among the 63 patients, our subjects in this study were 28 patients who were confirmed to have recurrence of IgA nephropathy by histopathological examination, and who had persistent urinary protein excretion levels of more than 300 mg/day despite medical treatments. Sixteen patients (group 1) underwent tonsillectomy alone, whereas the remaining 12 patients (group 2) did not receive tonsillectomy. The degree of proteinuria, kidney graft function, and blood pressure were analyzed retrospectively in the two patient groups.

RESULTS

The urinary protein excretion decreased dramatically after the tonsillectomy in all of the 16 patients of group 1 (880+/-630 mg/day to 280+/-220 mg/day, P<0.01) but none of group 2. The reduction in urinary protein excretion after tonsillectomy was especially marked in the patients with mild mesangial changes, such as minor glomerular abnormalities, when compared with that in patients with severe mesangial changes, such as diffuse proliferative glomerular abnormalities (mean percent decrease in the urinary protein excretion rate at 12 months after tonsillectomy; 31% minor glomerular abnormalities vs. 62% diffuse proliferative glomerular abnormalities, P<0.01).

CONCLUSION

These results suggest that in patients receiving oral immunosuppressive therapy for recurrence of IgA nephropathy after the kidney transplantation, reduction of the urinary protein excretion can be expected with tonsillectomy alone, without accompanying pulsed steroid therapy.

Tonsillectomy and steroid pulse (TSP) therapy for patients with IgA nephropathy: a nationwide survey of TSP therapy in Japan and an analysis of the predictive factors for resistance to TSP therapy

BACKGROUND

Tonsillectomy and steroid pulse (TSP) therapy was proposed as a curative treatment for IgA nephropathy by Hotta et al. (Am J Kidney Dis 38:736-742, 2001) based on data that about 50% of patients achieved clinical remission (CR) of urinary abnormalities.

MATERIALS AND METHODS

As a primary survey, we sent a questionnaire and letter to 848 hospitals in Japan, each of which employed a Fellow of the Japanese Society of Nephrology between October and December of 2006, in order to gather information about the prevalence and efficacy of TSP therapy for patients with IgA nephropathy. As a secondary survey, we collected data from both low- and high-CR-rate groups to determine which factors predicted resistance to TSP therapy.

RESULTS

A total of 2,746 patients received TSP therapy between 2000 and 2006. The CR rates, calculated by measuring urinary criteria 6 and 12 months after TSP therapy, were 32.0% (347/1,085) and 45.6% (452/991), respectively. Analysis of the 30 hospitals in which TSP therapy had been performed on at least ten patients revealed that the CR rates varied from below 10% to 100%. A secondary survey of ten hospitals revealed that, after correction of the CR rate from each hospital, patients could be categorized into three groups: those with a low CR rate (122 patients in four hospitals), a middle CR rate (78 patients in four hospitals), and a high CR rate (103 patients in two hospitals). The CR rate of all patients (N = 303) was 54.1%. A comparison of patient data between the low- and high-CR-rate groups showed a significant difference in age at onset (years; P = 0.05), amount of proteinuria (g/day; P = 0.02), total protein (g/dl; P = 0.02), pathological grade (P = 0.009), and prognostic score as described by Wakai et al. [Nephrol Dial Transplant 21:2800-2808, 2006, (P = 0.04)]. Univariate analysis revealed that there was a significant difference between non-CR and CR subgroups in duration from diagnosis until TSP therapy (6.9 +/- 6.8 versus 5.3 +/- 5.2 years; P = 0.02), amount of proteinuria (1.5 +/- 1.6 versus 0.8 +/- 0.8 g/day; P < 0.0001), serum creatinine (0.99 +/- 0.40 versus 0.87 +/- 0.34 mg/dl; P = 0.006), pathological grade (P = 0.0006), and Wakai et al.'s prognostic score (37.4 +/- 17.8 versus 28.1 +/- 15.1; P < 0.0001). A multivariate logistic analysis demonstrated that resistance to TSP therapy depends on age at onset, amount of proteinuria, hematuria grade, and pathological grade, and a score predicting resistance to TSP therapy could be derived by the formula: [(-0.0330) x (age) + (0.4772) x log (amount of proteinuria) - (0.0273) x (hematuria grade: 0, 1, 2, and 3) + (0.7604) x (pathological grade: 1, 2, 3, and 4) - 0.1894]. A receiver operating characteristic (ROC) curve showed that patients with a resistance score of greater than -0.02 easily resist TSP therapy (sensitivity 69%, specificity 75%, positive likelihood ratio 2.76).

CONCLUSION

TSP therapy shows promise as a treatment that can bring about CR of urinary abnormalities, but unfortunately the average CR rate is about 50% at 1 year after treatment. Predictive factors for resistance to TSP therapy are age at onset, amount of proteinuria, hematuria grade, and pathological grade. The present study suggests that patients with either early-stage or mild to moderate IgA nephropathy easily achieve CR following TSP therapy, whereas patients with late-stage or severe disease are prone to TSP therapy resistance.

Effect of tonsillectomy plus steroid pulse therapy on clinical remission of IgA nephropathy: a controlled study

BACKGROUND AND OBJECTIVES

Few well-designed investigations have examined how tonsillectomy plus steroid pulse therapy affects IgA nephropathy. A prospective, controlled study therefore was performed to compare the effects of combined therapy with those of steroid pulse alone in patients with IgA nephropathy.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Fifty-five patients were followed up for 54.0 +/- 21.2 mo. Thirty-five of them underwent tonsillectomy and steroid pulse therapy (group C), and 20 received steroid pulse monotherapy (group M). Both groups received methylprednisolone intravenously, followed by oral prednisolone (initial dosage 0.5 mg/kg per d) for 12 to 18 mo. Primary evaluation items were a 100% increase in serum creatinine from baseline levels or the disappearance of urinary protein (UP) and/or occult blood (UOB) indicating clinical remission.

RESULTS

At 24 mo after the initial treatment, the ratios of the UP and UOB disappearance were higher in group C than in group M, and the therapeutic effect persisted until the final observation. None of group C achieved a 100% increase in serum creatinine from the baseline level, whereas one patient in group M developed ESRD during the observation period. The histologic findings of repeated biopsy specimens from 18 patients revealed that mesangial proliferation and IgA deposition were significantly more reduced in group C than in group M. The Cox regression model showed that the combined therapy was approximately six-fold more effective in causing the disappearance of UP than steroid pulse monotherapy.

CONCLUSION

Tonsillectomy combined with steroid pulse treatment can induce clinical remission in patients with IgA nephropathy.

Histologically advanced IgA nephropathy treated successfully with prednisolone and cyclophosphamide

BACKGROUND

No definitive therapeutic consensus has been established for progressive immunoglobulin A nephropathy (IgAN).

METHODS

We retrospectively investigated 35 patients with histologically advanced IgAN. The patients were divided into two groups: 27 received prednisolone and cyclophosphamide (PSL+CPA group) and 8 received supportive treatment (control group). The initial doses of PSL and CPA were 30 mg/day and 50 mg/day, respectively. PSL was tapered to 2.5 mg/day over 2 years and CPA was discontinued at 6 months.

RESULTS

In the control group, mean follow-up duration was 22.9 months, renal progression rate was -20.9 x 10(-3) dl/mg per month, and all patients developed endstage renal disease within 5 years. In the PSL+CPA group, mean follow-up duration was 64.3 months, renal progression rate was -1.5 x 10(-3) dl/mg per month, and renal survival at 5 years was 89.8%. Renal prognosis was markedly improved in the PSL+CPA group compared with the control group. The patients in the PSL+CPA group were divided into two subgroups according to baseline serum creatinine (<2 mg/dl or > or =2 mg/dl); renal survival in the two subgroups was similar (84.4% versus 100% at 5 years). Adverse effects of PSL+CPA were minimal and mild.

CONCLUSIONS

It is possible that PSL+CPA therapy safely improved the renal prognosis of patients with severe IgAN who would otherwise have required dialysis therapy within 5 years. However, a prospective, multicenter clinical trial is required to prove the effects and safety of this treatment.

MPO-ANCA-positive IgA nephropathy successfully treated with tonsillectomy

A 20-year-old Japanese woman was admitted to a hospital because of gross hematuria. She was diagnosed with IgA nephropathy with a poor prognosis, based on the formation of many crescents in the glomerulus and monocyte infiltration in the interstitium in a renal biopsy specimen in February 2003. Myeloperoxidase (MPO)-antineutrophil cytoplasmic antibody (ANCA) was not identified at that time. After treatment with high-dose steroid pulse therapy and heparin/warfarin, her urinary protein improved, to 0.5 g/day. However, 1 year after the steroid pulse therapy, urinary protein was increased to 1.2 g/day, associated with repeated episodes of tonsillitis. A second renal biopsy was performed, and showed an improving tendency, compared to the findings of the previous one, although some crescent formation and adhesions of Bowman's capsule remained. Interestingly, MPO-ANCA was positive in the serological examination done at this time. One month and a half after the second renal biopsy, she had a tonsillectomy, followed by a regimen of 5 mg oral prednisolone daily, in order to prevent the progression of IgA nephropathy. After the tonsillectomy, her urinary protein level was markedly improved, at 0.14 g/day. Her creatinine clearance was ameliorated, at 102 ml/min, and in addition, MPO-ANCA had disappeared. This case suggests that an inflammation such as tonsillitis may be associated not only with the activity of IgA nephropathy but also with the production of MPO-ANCA.