Statins stabilize the renal function of IgA nephropathy

BACKGROUND

The renoprotective pleiotropic effect of 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) has recently been reported by several investigators. However, the effect of statins on IgA nephropathy (IgAN) is still unknown.

METHODS

We selected 24 IgAN patients who had newly started statin therapy and were not treated with steroids and immunosuppressive agents during the observation period. We analyzed and compared clinical findings 1 year before and after treatment.

RESULTS

Mean age was 50.5 ± 9.91 years and mean blood pressure was 90.9 ± 10.8 mmHg. Renal function was slightly deteriorated, serum creatinine was 1.03 (0.71-1.24) mg/dL and estimated glomerular filtration rate (eGFR) was 55.8 ± 22.8 mL/min. Lipid metabolism was poorly controlled [total cholesterol 247.7 ± 35.7 mg/dL, low-density lipoprotein cholesterol 151.5 (140.8-172.8) mg/dL, and triglyceride 163.0 (126.3-243.8) mg/dL]. Mild urinary abnormality was observed [proteinuria: 0.50 (0.22-1.29) g/g creatinine, urinary red blood cells 1.0 (0.2-5.0) per high power field]. After 1 year of statin treatment, lipid control was significantly better than at baseline. Proteinuria was not significantly decreased but renal function was improved. eGFR changed from a -5.9% decrease to a 2.4% increase (p = 0.0098).

CONCLUSION

Our results indicated that statins stabilized the renal function of IgAN patients independent of their reduction of proteinuria.

Serum uric acid levels and long-term outcomes in chronic kidney disease

Hyperuricemia is common in chronic kidney disease (CKD), but data regarding the relationship between serum uric acid levels and the long-term outcomes of CKD patients have been limited. The present study evaluated the associations between baseline serum uric acid levels with mortality and end-stage renal disease (ESRD). The subjects of this study were 551 stage 2-4 CKD patients. Cox proportional hazards models were used to evaluate the relationship between serum uric acid tertiles and all-cause mortality, cardiovascular disease (CVD) mortality, 50 % reduction in estimated glomerular filtration rate (eGFR), and development of ESRD, initially without adjustment, and then after adjusting for several groups of covariates. The mean age of the study subjects was 58.5 years, 59.3 % were men, and 10.0 % had diabetes. The mean eGFR was 42.02 ± 18.52 ml/min/1.73 m(2). In all subjects, the mean serum uric acid level was 6.57 ± 1.35 mg/dl, and 52.2 % of study subjects were on hypouricemic therapy (allopurinol; 48.3 %) at baseline. Thirty-one patients (6.1 %) died during a follow-up period of approximately 6 years. There was no significant association between serum uric acid level and all-cause mortality, CVD mortality, development of ESRD and 50 % reduction in eGFR in the unadjusted Cox models. In the adjusted models, hyperuricemia was found to be associated with all-cause mortality and CVD mortality after adjustment with CVD risk factors, kidney disease factors, and allopurinol, but not associated with development of ESRD and 50 % reduction in eGFR. The results of this study showed that hyperuricemia but not serum uric acid levels were associated with all-cause mortality, CVD mortality after adjustments with CVD risk factors, kidney disease factors, and allopurinol in stage 2-4 CKD patients.

Clinical and pathological studies of IgA nephropathy presenting as a rapidly progressive form of glomerulonephritis

OBJECTIVE

IgA nephropathy (IgAN) is widely regarded as a slowly progressive disease. However, a minor population of patients present with a rapidly progressive form of glomerulonephritis (RPGN).

METHODS

We studied 25 cases of IgAN who presented with RPGN. The laboratory data, histology, and five-year prognosis after diagnostic renal biopsy were evaluated. We compared the data of these patients with those of 495 patients with the non-RPGN type. In addition, we divided the patients with the RPGN type of IgAN into a group with reduced renal function and a group with maintained renal function, and compared the data between the two groups.

RESULTS

In the 'RPGN type', the serum creatinine levels and a 24-hour urinary protein excretion were significantly higher than in the non-RPGN type. Histological examinations showed that the rates of endocapillary hypercellularity and tubular atrophy/interstitial fibrosis were significantly higher in the patients with the RPGN type. In the comparison between the groups with reduced and maintained renal functions, the former group exhibited higher levels of proteinuria, serum creatinine and crescent formation than the latter group.

CONCLUSION

The RPGN type of IgAN was significantly worse in terms of the renal survival rate at five years than the non-RPGN type. Intensive and active treatments are necessary for this minor population, according to the guideline for the management of RPGN.

Effects of combination therapy with renin-angiotensin system inhibitors and eicosapentaenoic acid on IgA nephropathy

OBJECTIVE

The beneficial effects of renin-angiotensin-aldosterone system inhibitors (RASI) and the omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA) on IgA nephropathy (IgAN) have been reported. However, it is unknown whether these agents have any synergistic interactions.

METHODS

We divided 38 IgAN patients into two groups: an EPA group (n=18) treated with RASI plus EPA and a DILAZEP group (n=20) treated with RASI plus dilazep dihydrochloride. We analyzed the clinical and histological background of each patient, any relevant clinical findings obtained one year after treatment and any factors significantly related to decreases in proteinuria.

RESULTS

The clinical findings were largely similar between the groups, except for body mass index (24.9±4.5 in the EPA group vs. 21.4±2.1 in the DILAZEP group, p=0.0041) and total cholesterol (median: 206.0 vs. 177.5 mg/dL, p=0.0493). The histological findings, evaluated according to the Oxford classification, were also similar between the groups. At one year after treatment, the EPA group demonstrated a significantly decreased mean blood pressure (from 94.7±9.0 to 86.4±7.2 mmHg, p=0.0007) and a significantly decreased median level of proteinuria (from 0.80 to 0.41 g/g creatinine, p<0.001). In the DILAZEP group, the mean blood pressure significantly decreased (from 95.2±13.2 to 88.1±7.7 mmHg, p<0.001) without any significant decrease in the median level of proteinuria (from 0.88 to 0.60 g/g creatinine). According to a multivariate logistic analysis, EPA was found to be the only independent factor related to decreases in proteinuria (odds ratio = 5.073, 95% CI: 1.18-26.7, p=0.0285).

CONCLUSION

We conclude that EPA accelerates the effects of RASI and thus decreases the proteinuria observed in patients with IgAN.

Effect of single-dose rituximab on steroid-dependent minimal-change nephrotic syndrome in adults

BACKGROUND

Steroid-dependent minimal-change nephrotic syndrome (MCNS) requires administration of prolonged courses of prednisolone (PSL); therefore, a paradigm shift from such toxic 'non-specific' therapies to selective immunomodulating regimens is necessary for these cases.

METHODS

To assess the therapeutic effects of rituximab (an anti-CD20 antibody) in adult patients with steroid-dependent MCNS, we performed a prospective trial of the effects of a single dose of rituximab administered twice at an interval of 6 months in 25 MCNS patients. We evaluated the biochemical parameters and compared the clinical findings between the 12-month period before and 12-month period after the first rituximab infusion.

RESULTS

A significant reduction in the number of relapses and the total dose and the maintenance dose of PSL administered was observed during the 12-month period after the first rituximab infusion when compared with the findings during the 12-month period before the first rituximab infusion [25 (100%) versus 4 (16%), P < 0.001; 8.2 versus 3.3 g, P < 0.001; 26.4 mg/day at baseline versus 1.1 mg/day at 12-month, P < 0.0001]. Complete remission was achieved/maintained in all patients undergoing B-cell depletion. Four of 17 patients with B-cell repletion developed relapse.

CONCLUSIONS

Our results revealed that rituximab therapy was associated with a reduction in the number of relapses and in the total dose of PSL needed. Therefore, rituximab appears to be a useful therapeutic agent for adult patients with steroid-dependent MCNS. These results suggest that this treatment is rational and should be considered as an important option in the management of adult patients with steroid-dependent MCNS.

Synthesis of a chitosan derivative soluble at neutral pH and gellable by freeze-thawing, and its application in wound care

Conventional chitosan hydrogels exhibit an acidic nature and contain unfavorable additives because (i) chitosan is soluble only in acidic solutions and (ii) toxic chemicals or proteins of non-human origin that serve as antigens are necessary for preparing chitosan hydrogels. These characteristics of the chitosan hydrogels limit their possibilities as wound dressings. In this study, a chitosan-gluconic acid conjugate is developed, soluble in an aqueous solution at neutral pH and gellable by freeze-thawing (cryogelation) without using additives. The viability of L929 fibroblasts cultured in the presence of the chitosan derivative for 24 h was >96%. The degradation rate of the corresponding chitosan cryogels by lysozyme was tunable via the derivative concentration in the gels. The gels had low cellular adhesiveness. The gels promoted the accumulation of inflammatory cells such as polymorphonuclear leukocytes, which have the potential to release chemical mediators effective for wound healing, in full-thickness skin wounds in rats and accelerated the healing of the wounds. These results demonstrate that cryogels are promising for wound care.

Rituximab treatment for adult patients with focal segmental glomerulosclerosis

We present two cases with steroid-resistant nephrotic syndrome (SRNS) and two cases with steroid-dependent nephrotic syndrome (SDNS) due to focal segmental glomerulonephritis (FSGS) who were treated with a single dose of rituximab (375 mg/m(2)). Although the two cases with SRNS showed no response, the two cases with SDNS achieved complete remission. The patients in whom the peripheral B-cell counts subsequently increased after the administration of rituximab demonstrated a relapse. Rituximab may be an effective treatment agent for SDNS with FSGS and the peripheral B-cell count may be a useful marker in such patients for preventing disease relapse.

Comparison of inhibitors of renin-angiotensin-aldosterone system (RAS) and combination therapy of steroids plus RAS inhibitors for patients with advanced immunoglobulin A nephropathy and impaired renal function

BACKGROUND

The adaptation of steroid therapy and the effect of renin-angiotensin-aldosterone system inhibitors (RASIs) for advanced immunoglobulin A nephropathy (IgAN) patients with impaired renal function are still controversial.

METHODS

We divided 63 IgAN patients with an estimated glomerular filtration rate (eGFR) of <60 ml/min/1.73 m(2) and proteinuria ≥ 0.5 g/day into two groups: the RASI group (RASI, n = 33), treated with RASIs alone; and the combination group (COMBI, n = 30), treated with corticosteroids and RASIs. We analyzed the clinical and histological background, renal survival rate, and the risk factors for progression.

RESULTS

Renal function (mean eGFR: COMBI 46.4 vs. RASI 47.0 ml/min/1.73 m(2)), the amount of proteinuria (median: COMBI 1.39 vs. RASI 1.17 g/g creatinine) and histological backgrounds were not significantly different between the groups, but urinary red blood cells (U-RBCs) were significantly higher in the COMBI group than in the RASI group (median: COMBI 30.0 vs. RASI 10.0 counts/high-power field, P = 0.0171). The serial change in proteinuria did not differ until 5 years after treatment, but U-RBCs were significantly decreased in both groups (P < 0.0001), and eGFR was significantly decreased in the RASI group (P < 0.001) but not in the COMBI group. The results for each year after treatment did not differ significantly between both groups. The renal survival rate was not significantly different between the groups. There was no independent risk factor for progression by Cox regression analysis.

CONCLUSION

Combination therapy with steroids and RASIs was not superior to monotherapy with RASIs for advanced IgAN with impaired renal function.

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.

Long-term beneficial effects of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker therapy for patients with advanced immunoglobulin A nephropathy and impaired renal function

BACKGROUND

There are few reports analyzing the effects of angiotensin-converting enzyme inhibitors (ACEIs) and/or angiotensin receptor blockers (ARBs) on the long-term renal survival of advanced immunoglobulin A nephropathy (IgAN) patients.

PATIENTS AND METHODS

In this retrospective cohort analysis, we divided 66 IgAN patients with an estimated glomerular filtration rate (eGFR) <60 ml/min into three groups: ACEI group (n = 20, treated with ACEIs), ARB group (n = 23, treated with ARBs), and control group (n = 23, treated with antiplatelet agents), and analyzed the clinical and histological background, renal survival rate until the primary endpoint of 50% decrease of eGFR from baseline, and the secondary endpoint of progression to end-stage renal disease, and the risk factors for progression.

RESULTS

The clinical and histological background without serum IgA and C3 were not significantly different among the three groups. The renal survival rate until the primary and secondary endpoints was significantly higher in the ACEI and ARB groups than in the control group. The independent risk factors for progression were higher mean blood pressure (hazard ratio [HR] 1.76, P = 0.04), higher histological grade (HR 2.54, P = 0.0184) at baseline, and without ACEIs or ARBs (HR 7.09, P = 0.001), but decreased proteinuria and blood pressure. The risk factors with resistance to ACEIs or ARBs were higher blood pressure and lower eGFR at baseline. There was no difference regarding the survival rate and the risk for progression between ACEI s and ARBs.

CONCLUSION

ACEIs or ARBs were effective for long-term renal survival of advanced IgAN, although proteinuria and blood pressure did not decrease.

Beneficial effect of aliskiren combined with olmesartan in reducing urinary protein excretion in patients with chronic kidney disease

BACKGROUND

Blockade of the renin-angiotensin-aldosterone system is a therapeutic mainstay in patients with chronic kidney disease (CKD). However, the renoprotective effect of the novel direct renin inhibitor aliskiren is unknown.

MATERIALS AND METHODS

We performed a prospective study in 10 CKD patients. All 10 patients with persistent proteinuria (urinary protein-to-creatinin ratio 0.3-3.5 g/g), despite good blood pressure control (<130/80 mmHg) with olmesartan, were started on 150 mg/day aliskiren. Clinical parameters were examined before and after 4, 8, 12, and 16 weeks of treatment.

RESULTS

Urinary protein-to-creatinine ratio significantly decreased by about 40% at 16 weeks from baseline (P = 0.0002), although estimated glomerular filtration rate and blood pressure did not change throughout the study period. Plasma renin activity also decreased significantly from baseline (P = 0.019), although plasma aldosterone concentration did not change.

CONCLUSIONS

Aliskiren combined with olmesartan reduces proteinuria in CKD patients.

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.

The significance of caveolae in the glomeruli in glomerular disease

AIMS

The aim of this study was to demonstrate expression of cell membrane invagination 'caveolae' in glomeruli and to correlate this with functional and structural characteristics of the human glomerular diseases.

METHODS

The expression of caveolin-1 (Cav-1), which is the main component of caveolae, was examined in the glomeruli, and the relationship between Cav-1 expression and pathological and clinical findings was determined in 99 patients with glomerular disease and in 50 renal transplantation donors as controls.

RESULTS

Cav-1 was expressed very weakly in the controls, and the area of Cav-1 expression relative to the total glomerular area was 0.57±0.65%. However, the area of Cav-1 expression was significantly larger in each glomerular disease (IgA nephropathy, 1.05±1.36%, p<0.05; crescent glomerulonephritis, 1.86±1.19%, p<0.001; minimal change disease, 2.38±1.24%, p<0.001; focal segmental glomerulosclerosis, 2.88±2.05%, p<0.01; membranous nephritis, 4.27±2.95%, p<0.001; membranoproliferative glomerulonephritis, 4.49±3.15%, p<0.001; and diabetic nephropathy, 2.45±1.52%, p<0.001; compared with the controls. Cav-1 expression was significantly decreased in glomerular disease treated with steroids. Co-localisation of Cav-1 and the endothelial marker 'pathologische anatomie leiden-endothelium' was prominent in an immunofluorescence study, and caveolae on the glomerular endothelial cells were observed in electron microscopy.

CONCLUSIONS

The expression of Cav-1 was significantly increased in the glomeruli of patients with glomerular disease, and it was related to urinary albumin excretion. Cav-1 expression and caveolae were observed in glomerular endothelial cells. It is hypothesised that they play a role in the recovery phase of capillary injury or endocytosis of albumin into endothelial cells. Basic research should be performed to elucidate the role played by Cav-1 and caveolae.

Preparation of New Bismuth Oxides by Hydrothermal Reaction

Hydrothermal reactions using NaBiO3·nH2O produced a variety of newbismuth oxides that were not prepared by high temperature reaction. Some of them have pentavalent bismuth such as Bi2O4O, LiBiO3, ABi2O6 (A = Mg, Zn) and AgBiO3. When using transition metal or rare-earth metal solutions, new bismuth oxides with trivalent bismuth were obtained. In the case of Cr(NO3)3 solution a chromium bismuth oxyhydroxide, HBi3(CrO4)2O3, was prepared at 180°C, while in A2CrO4 (A = Li, Na, K) solution a new bismuth chromium oxide, Bi8(CrO4)O11, was prepared above 180°C. When A2MoO4 (A = Li, Na, K) solution was used, a new phase appeared above 220°C. By using A2WO4 (A = Li, Na, K) solution β-Bi2O3 and Bi2WO6 were obtained above 220°C.

A case of pulmonary dialysis-related amyloidosis with reticular opacity of the lung in a patient undergoing long-term dialysis

Dialysis-related amyloidosis (DRA) is one of the most important complications in long-term dialysis patients. Pulmonary involvement in patients with DRA has been rarely described, and lung radiographic findings have not yet been reported. The most common chronic lung disease process in chronic dialysis patients is interstitial fibrosis. This is the first case report of DRA presenting in the lung in a manner resembling interstitial pneumonia. This case study suggests that interstitial pneumonia as a result of DRA should be considered when dyspnoea and reticular opacity of the lung are observed in patients undergoing long-term dialysis.

[Successful rituximab therapy for MALT lymphoma complicating cryoglobulinemic glomerulonephritis]

We report a case of nephrotic syndrome associated with MALT lymphoma. The patient was a 66-year-old woman who had a 21-year history of MALT lymphoma. She was admitted to our hospital for the evaluation of systemic edema and purpura during two months. Urinary protein excretion was quantified at 3.3 g/24h. Serum creatinine was elevated to 1.63 mg/dL. An immunoserological investigation showed the presence of IgM-kappa type monoclonal cryoglobulin accompanied by a decreased serum complement level. HCV infection was negative. A renal biopsy specimen revealed membranoproliferative glomerulonephritis (MPGN) with cryoglobulin deposition and focal atypical lymphoid cells infiltration in the renal interstitium. Immunoperoxidase staining of the atypical lymphoid cell population was positive for CD20 and CD79. Combined therapy with prednisolone, plasma exchange and rituximab was commenced. Her proteinuria disappeared and renal function improved after rituximab therapy. In our case, nephrotic syndrome due to cryoglobulinemic glomerulonephritis was successfully treated mainly by rituximab.