The association between high-dose allopurinol and erythropoietin hyporesponsiveness in advanced chronic kidney disease. JOINT-KD study

INTRODUCTION

To explore the association between urate-lowering agents and reduced response to erythropoietin-stimulating agents in patients suffering from chronic kidney disease G5.

METHODS

We conducted a cross-sectional, multicenter study in Japan between April and June 2013, enrolling patients aged 20 years or older with an estimated glomerular filtration rate of ≤15 mL/min/1.73 m2. Exclusion criteria encompassed patients with a history of hemodialysis, peritoneal dialysis, or organ transplantation. The patients were categorized into four groups based on the use of urate-lowering drugs: high-dose allopurinol (>50 mg/day), low-dose allopurinol (≤50 mg/day), febuxostat, and no-treatment groups. We used a multivariable logistic regression model, adjusted for covariates, to determine the odds ratio (OR) for erythropoietin hyporesponsiveness, defined by an erythropoietin resistance index (ERI) of ≥10, associated with urate-lowering drugs.

RESULTS

A total of 542 patients were included in the analysis, with 105, 36, 165, and 236 patients in the high-dose allopurinol, low-dose allopurinol, febuxostat, and no-treatment groups, respectively. The median and quartiles of ERIs were 6.3 (0, 12.2), 3.8 (0, 11.2), 3.4 (0, 9.8), and 4.8 (0, 11.2) in the high-dose allopurinol, low-dose allopurinol, febuxostat, and no-treatment groups, respectively. The multivariate regression model showed a statistically significant association between the high-dose allopurinol group and erythropoietin hyporesponsiveness, compared to the no-treatment group (OR=1.98, 95% confidence interval: 1.10-3.57).

CONCLUSIONS

Our study suggests that the use of high-dose allopurinol exceeding the optimal dose may lead to hyporesponsiveness to erythropoiesis-stimulating agents.

Phase 2 study of upacicalcet in Japanese haemodialysis patients with secondary hyperparathyroidism: an intraindividual dose-adjustment study

Background

Upacicalcet is a novel small-molecule calcimimetic agent developed for intravenous injection. Here, we evaluated the long-term efficacy and safety of upacicalcet treatment via intraindividual dose adjustment in haemodialysis patients with secondary hyperparathyroidism (SHPT).

Methods

A phase 2, multicentre, open-label, single-arm study was conducted. Upacicalcet was administered for 52 weeks; the starting dose was 50 μg thrice a week, and then adjusted to 25, 50, 100, 150, 200, 250, or 300 μg, according to the dose-adjustment method set in the protocol. The primary endpoint was the percentage of patients with serum intact parathyroid hormone (iPTH) level achieving a target range of 60-240 pg/mL (target achievement rate) at week 18.

Results

A total of 58 patients were administered upacicalcet. The target achievement rate of serum iPTH level at week 18 was 57.9%, which increased to 80.8% at week 52. The serum-corrected calcium (cCa) level decreased immediately after upacicalcet administration, but no further decrease was observed. Adverse events were observed in 94.8% of patients, and adverse drug reactions (ADRs) occurred in 20.7% of patients. The most common ADR was decreased adjusted calcium in eight patients; dizziness occurred as a serious ADR in one patient. The serum cCa level of patients who interrupted upacicalcet treatment at a serum cCa level of <7.5 mg/dL recovered to ≥7.5 mg/dL immediately after the interruption.

Conclusions

In haemodialysis patients with SHPT, upacicalcet doses of 25-300 μg for 52 weeks were found to be highly effective and well-tolerated, with minor safety concerns.

Long-term safety and decrease of pill burden by tenapanor therapy: a phase 3 open-label study in hemodialysis patients with hyperphosphatemia

Phosphate binders (PBs) generally have a high pill burden. Tenapanor selectively inhibits sodium/hydrogen exchanger isoform 3, reducing intestinal phosphate absorption. Tenapanor is a novel drug administered as a small tablet, twice daily. This multicenter, open-label, single-arm, phase 3 study aimed to evaluate the long-term safety of tenapanor and its efficacy in decreasing PB pill burden. Tenapanor 5 mg twice daily was administered to hemodialysis patients with serum phosphorus level 3.5-7.0 mg/dl at baseline; the dose could be increased up to 30 mg twice daily. Patients could also switch from PBs. The primary endpoint was safety during 52-week administration. The key secondary endpoint was a ≥ 30% reduction in the total pill number of daily PBs and tenapanor from baseline. Of 212 patients starting treatment, 154 completed the study. Diarrhea was the most frequent adverse event, occurring in 135 patients (63.7%); most events were classified as mild (74.8%). No clinically significant changes occurred other than serum phosphorus level. At Week 52/discontinuation, 158/204 patients (77.5%) achieved the key secondary endpoint. Complete switching from PBs to tenapanor was achieved in 50-76 patients (26.7%-41.5%), and 80 patients (51.9%) at Week 8-12 and Week 50, respectively. Serum phosphorus remained generally stable within the target range (3.5-6.0 mg/dl). These findings suggest the long-term safety and tolerability of tenapanor. Tenapanor could reduce or eliminate PB pill burden while controlling serum phosphorus levels.Trial registration: NCT04771780.

Efficacy and Safety of Upacicalcet in Hemodialysis Patients with Secondary Hyperparathyroidism: A Randomized Placebo-Controlled Trial

BACKGROUND

Secondary hyperparathyroidism is a major complication of patients undergoing hemodialysis (HD). Upacicalcet, a new injectable calcimimetic, acts on calcium-sensing receptors to suppress parathyroid hormone (PTH) secretion. We examined the efficacy and safety of upacicalcet in patients with secondary hyperparathyroidism receiving HD.

METHODS

In this phase 3, double-blind, placebo-controlled study, we randomized Japanese patients undergoing HD with serum intact PTH (iPTH) concentrations >240 pg/ml and corrected calcium concentrations ≥8.4 mg/dl. Either upacicalcet or placebo was administered after each HD session for 24 weeks. The primary outcome was the percentage of participants achieving the target mean serum iPTH concentration (60-240 pg/ml) at weeks 22-24.

RESULTS

A total of 103 participants received upacicalcet, and 50 participants received the placebo. The percentage of participants achieving mean serum iPTH concentrations of 60-240 pg/ml during the evaluation period was 67% (69/103) in the upacicalcet group and 8% (4/50) in the placebo group. The difference between the two groups was 59% (95% confidence interval, 48% to 71%). Upacicalcet also decreased serum fibroblast growth factor-23, bone-specific alkaline phosphatase, total type 1 procollagen-N-propeptide, and tartrate-resistant acid phosphatase-5b concentrations. Adverse events were reported in 85% (88/103) and 72% (36/50) participants in the upacicalcet and placebo groups, respectively. The incidence of upper gastrointestinal adverse events, such as nausea and vomiting, was similar between the two groups. Serum corrected calcium concentrations <7.5 mg/dl were observed in 2% of participants in the upacicalcet group and no participants in the placebo group.

CONCLUSIONS

Upacicalcet, a novel injectable calcimimetic, is effective and safe for secondary hyperparathyroidism patients receiving HD.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Phase 3 Study of SK-1403, NCT03801980 .

Effects of evocalcet on parathyroid calcium-sensing receptor and vitamin D receptor expression in uremic rats

Little is known about the effect of the recently developed calcimimetic evocalcet (Evo) on parathyroid calcium-sensing receptor (CaSR) and vitamin D receptor (VDR) expression. We examined the effects of Evo and cinacalcet (Cina) on CaSR and VDR expression in 5/6 nephrectomized Sprague-Dawley rats fed a high-phosphorus diet for 4 weeks to develop secondary hyperparathyroidism (SHPT). These uremic rats were divided into 4 groups-baseline control (Nx4W) and groups with additional treatment with either the Vehicle, Evo, or Cina for 2 weeks; normal rats were used as normal controls (NC). Blood parameters and parathyroid tissue were analyzed. CaSR and VDR expression levels were determined using immunohistochemistry. The degree of kidney injury and hyperphosphatemia was similar in the uremic groups (Nx4W, Vehicle, Cina, and Evo). Serum parathyroid hormone levels were significantly higher in the Nx4W and Vehicle groups than in the NC group. This increase was significantly suppressed in the Cina and Evo groups compared with that in the Vehicle group. Serum calcium levels were significantly and equally lower in the Cina and Evo groups relative to those in the Vehicle group. CaSR expression was significantly lower in the Nx4W and Vehicle groups than in the NC group. This downregulation was of an equally lesser magnitude in the Cina and Evo groups. A similar trend was observed for VDR expression. These results indicate that Evo and Cina treatment can increase parathyroid CaSR and VDR expression in uremic rats with SHPT, which could provide better control of mineral and bone disorder markers.

Fibroblast Growth Factor 23 Exacerbates Cardiac Fibrosis in Deoxycorticosterone Acetate-Salt Mice With Hypertension

Fibroblast growth factor 23 (FGF23) is associated with cardiovascular disease in patients with chronic kidney disease; however, the mechanisms underlying the effect of FGF23 on cardiac function remain to be investigated. Herein, we studied the effect of continuous intravenous (CIV) FGF23 loading in a deoxycorticosterone acetate (DOCA)-salt mouse model with mild chronic kidney disease and hypertension as well as heart failure with a preserved ejection fraction. Wild-type male mice were randomly allocated to 4 groups: normal control, vehicle-treated DOCA-salt mice, FGF23-treated DOCA-salt mice, and FGF23- and calcitriol-treated DOCA-salt mice. The DOCA-salt mice received the agents via the CIV route for 10 days using an infusion minipump. DOCA-salt mice that received FGF23 showed a marked increase in the serum FGF23 level, and echocardiography in these mice revealed heart failure with a preserved ejection fraction. These mice also showed exacerbation of myocardial fibrosis, concomitant with an inverse and significant correlation with Cyp27b1 expression. Calcitriol treatment attenuated FGF23-induced cardiac fibrosis and improved diastolic function via inhibition of transforming growth factor-β signaling. This effect was independent of the systemic and local levels of FGF23. These results suggest that CIV FGF23 loading exacerbates cardiac fibrosis and that locally abnormal vitamin D metabolism is involved in this mechanism. Calcitriol attenuates this exacerbation by mediating transforming growth factor-β signaling independently of the FGF23 levels.

First-in-Patient Phase I/II Study of Upacicalcet in Japanese Patients with Secondary Hyperparathyroidism Undergoing Hemodialysis: Pharmacokinetic and Pharmacodynamic Properties

Objective

Upacicalcet is a new renally excreted and injectable calcimimetic agent. We evaluated the pharmacokinetics, pharmacodynamics, safety, and tolerability of single and multiple intravenous administration of upacicalcet in patients with secondary hyperparathyroidism undergoing hemodialysis.

Methods

This study was a multicenter, randomized, placebo-controlled, double-blinded, dose-escalation study consisting of a single-dose study and a multiple-dose study. The single-dose study consisted of seven dose steps from 0.025 to 0.8 mg. For each step, six patients were randomly assigned 2:1 to receive upacicalcet or a placebo. The multiple-dose study occurred over 3 weeks in three-dose steps from 0.05 to 0.2 mg. For each step, 12 patients were randomly assigned 3:1 to receive upacicalcet or a placebo.

Results

The plasma concentration of upacicalcet increased in a dose-dependent manner and was maintained for the next dialysis. Upacicalcet was approximately 80% removed by a single dialysis and did not increase in the plasma concentration with repeated administration. Serum intact parathyroid hormone and corrected calcium (Ca²⁺) levels tended to decrease in response to the plasma concentration of upacicalcet. In the single-dose study, upper gastrointestinal symptoms were observed as a non-serious and mild adverse drug reaction in the groups receiving upacicalcet ≥ 0.4 mg. In the multiple-dose study, abdominal discomfort occurred in each patient in the 0.1 mg and 0.2 mg groups.

Conclusions

Upacicalcet for patients with secondary hyperparathyroidism undergoing hemodialysis could be a calcimimetic agent that acts in a dose-dependent manner and persistently until the next dialysis session. No safety or tolerability issues specific to upacicalcet were found.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40262-022-01139-w.

First-in-Human Phase I Study of the Novel Injectable Calcimimetic Agent Upacicalcet in Healthy Adult Japanese Participants

Background and Objective

Upacicalcet sodium hydrate is a novel small-molecule calcimimetic and has potential as a therapeutic agent for secondary hyperparathyroidism. We assessed the pharmacokinetics, pharmacodynamics, safety, and tolerability of a single intravenous dose of upacicalcet in Japanese healthy adults.

Method

This was a single-center, double-blinded, randomized, placebo-controlled, dose-escalation study. For each cohort, eight subjects were randomly assigned at a ratio of 3:1 to receive a single injection of placebo or upacicalcet 0.01, 0.1, 1.0, or 2.5 mg.

Result

The plasma concentration of upacicalcet increased in a dose-dependent manner. Upacicalcet rapidly disappeared from plasma after administration. The half-life of upacicalcet was approximately 1–2 h. The major excretion route of upacicalcet was via urine. Serum intact parathyroid hormone decreased in accordance with the upacicalcet dose, from the lowest dose of 0.01 mg. Gastrointestinal disorders occurred in one patient in the 1.0 mg group and in five patients in the 2.5 mg group. All adverse events were nonserious, and no symptomatic hypocalcemia occurred.

Conclusion

This study showed that upacicalcet acted as a calcimimetic and was excreted in the urine unchanged with little metabolism. Moreover, upacicalcet is a small molecule and has a small volume of distribution. In addition, less than 50% of upacicalcet binds to human plasma proteins. These findings suggest that upacicalcet administered to patients undergoing hemodialysis might be expected to have a long excretion period and sustained pharmacological effect.

Biopsy-proven Streptococcus suis-associated Infectious Glomerulonephritis

A 64-year-old Japanese man who worked at a butcher shop was hospitalized for a fever, headache, and deafness. We diagnosed him with sepsis and meningitis caused by Streptococcus suis infection. The patient's renal function declined rapidly, and hemodialysis was performed temporarily. A renal biopsy was performed, and the renal function tended to improve with antimicrobial therapy. This case seemed rather similar to one of staphylococcal-associated nephritis in that it showed mesangial proliferative nephritis with immunoglobulin A deposition, even though the nephritis was caused by streptococci. Similarly, intramembranous electron-dense deposits were characteristic findings. We present new findings of an in vivo renal biopsy in a case of S. suis-associated glomerulonephritis.

Corrigendum to "Efficacy of evocalcet in previously cinacalcet-treated secondary hyperparathyroidism patients," [Kidney Int. Rep. 2021; https://doi.org/10.1016/j.ekir.2021.08.020]

[This corrects the article DOI: 10.1016/j.ekir.2021.08.020.].

Efficacy of Evocalcet in Previously Cinacalcet-Treated Secondary Hyperparathyroidism Patients

Introduction

Evocalcet is a recently approved calcimimetic agent for secondary hyperparathyroidism (SHPT). In this study, the efficacy and safety of once-daily oral evocalcet were evaluated in patients without prior cinacalcet use (nonusers) and previously treated patients (users).

Methods

This post hoc analysis of a previous phase III head-to-head comparison study included SHPT patients treated with evocalcet with or without prior cinacalcet use. Endpoints included trends in the median intact and whole parathyroid hormone (PTH), mean corrected calcium, phosphate, and bone metabolic markers, and whole-to-intact PTH ratios throughout the 30-week study period; proportions of patients achieving target intact PTH, corrected calcium, and phosphate at weeks 28 to 30; and adverse drug reactions (ADRs).

Results

This study included 127 nonusers and 190 users with significant differences in age; duration of dialysis; use of intravenous vitamin D receptor activators; levels of intact PTH, corrected calcium, tartrate-resistant acid phosphatase 5b, procollagen type 1 N-terminal-propeptide; and largest parathyroid gland volume (P < 0.05 for all characteristics) between 2 groups at baseline. Users required higher evocalcet dosages than nonusers. Similar efficacy results were found in the 2 groups except for a significantly higher proportion of nonusers achieving the intact PTH target (81.6% vs 67.1%, difference [95% confidence interval], −14.5% [−24.59, −3.34]), and a significant reduction in largest parathyroid gland volume from week 0 to week 30 (−120.6 [567.2] mm³, P = 0.043). No difference was found in ADRs between the 2 groups.

Conclusion

Treatment with evocalcet is effective and safe irrespective of prior cinacalcet treatment in SHPT patients.

Positive renal familial history in IgA nephropathy is associated with worse renal outcomes: a single-center longitudinal study

Background

IgA nephropathy (IgAN) is the most common primary glomerulonephritis worldwide. Although most IgAN cases are sporadic, few show a familial aggregation. However, the prevalence and prognosis of IgAN individuals with positive familial history (FH) of renal disorders remains uncertain. To address these issues, we conducted a longitudinal observational study on a single-institution cohort of patients with biopsy-proven IgAN.

Methods

A total of 467 IgAN patients who underwent renal biopsy during 1994 to 2019 were ascertained to have positive- or negative-FH by history taking and were followed for an average of 8.9 years. We compared the clinical and pathological features of the two subgroups. The primary outcome, a composite of a hard endpoint (end-stage renal disease [ESRD]) and surrogate endpoint (a 50% or more reduction in the estimated glomerular filtration rate [eGFR] from baseline), was evaluated. To estimate the risk for progression to ESRD, a Cox proportional hazards analysis was performed for a subset of patients who underwent follow-up for > 2 years and had an eGFR > 30 mL/min/1.73 m² at baseline (n = 389; observation, 8.7 years).

Results

Positive-FH subtype accounted for 11.6% (n = 54) of all IgAN patients. At baseline, there were no significant differences between the positive- and negative-FH subgroups regarding age, sex, comorbid disease, MEST-C score, observation period, and therapeutic interventions. However, the eGFR value at baselines was significantly lower in the positive-FH subgroup than in the negative-FH subgroup (P < 0.01). On multivariate analysis, positive-FH emerged an independent determinant of poorer renal outcomes (odds ratio, 2.31; 95% confidence interval, 1.10–4.85; P = 0.03), after adjusting for confounding factors. eGFR at follow-up was significantly lower in the positive-FH subgroup than in the negative-FH subgroup after adjustment for age and observation period.

Conclusions

Positive-FH was found in 11.6% of all IgAN patients, consistent with the incidence seen in previous literature. A significantly lower eGFR at baseline and last follow-up and unfavorable renal outcomes in the positive-FH subgroup suggest that certain genetic risk factors predisposing to renal failure may exist in a fraction of our IgAN cohort. (331 words).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02425-8.

Granulomatosis with polyangiitis in a patient with a thoracic vertebral lesion: a case report

Granulomatosis with polyangiitis is a systemic, small vessel vasculitis associated with the anti-neutrophil cytoplasmic antibody. We herein report a case of granulomatosis with polyangiitis with paravertebral lesions. A 69-year-old man presented to our hospital with fever, back pain, and myalgia. A computed tomography scan showed multiple lung nodules, while magnetic resonance imaging revealed soft tissue shadows around a thoracic vertebral lesion. A laboratory examination revealed positive myeloperoxidase anti-neutrophil cytoplasmic antibody. He was diagnosed with granulomatosis with polyangiitis. He was treated with oral glucocorticoid and intravenous cyclophosphamide, and the shadows resolved. Physicians should consider granulomatosis with polyangiitis in cases with paravertebral lesions.

Optimal Phosphate Control Related to Coronary Artery Calcification in Dialysis Patients

BACKGROUND

In patients on maintenance dialysis, cardiovascular mortality risk is remarkably high, which can be partly explained by severe coronary artery calcification (CAC). Hyperphosphatemia has been reported to be associated with the severity of CAC. However, the optimal phosphate range in patients on dialysis remains unknown. This study was planned to compare the effects on CAC progression of two types of noncalcium-based phosphate binders and of two different phosphate target ranges.

METHODS

We conducted a randomized, open-label, multicenter, interventional trial with a two by two factorial design. A total of 160 adults on dialysis were enrolled and randomized to the sucroferric oxyhydroxide or lanthanum carbonate group, with the aim of reducing serum phosphate to two target levels (3.5-4.5 mg/dl in the strict group and 5.0-6.0 mg/dl in the standard group). The primary end point was percentage change in CAC scores during the 12-month treatment.

RESULTS

The full analysis set included 115 patients. We observed no significant difference in percentage change in CAC scores between the lanthanum carbonate group and the sucroferric oxyhydroxide group. On the other hand, percentage change in CAC scores in the strict group (median of 8.52; interquartile range, -1.0-23.9) was significantly lower than that in the standard group (median of 21.8; interquartile range, 10.0-36.1; P=0.006). This effect was pronounced in older (aged 65-74 years) versus younger (aged 20-64 years) participants (P value for interaction =0.003). We observed a similar finding for the absolute change in CAC scores.

CONCLUSIONS

Further study with a larger sample size is needed, but strict phosphate control shows promise for delaying progression of CAC in patients undergoing maintenance hemodialysis.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Evaluate the New Phosphate Iron-Based Binder Sucroferric Oxyhydroxide in Dialysis Patients with the Goal of Advancing the Practice of EBM (EPISODE), jRCTs051180048.

A case of myeloperoxidase-antineutrophil cytoplasmic antibody and anticardiolipin antibody-positive pyogenic arthritis, pyoderma gangrenosum, acne and hidradenitis suppurativa (PAPASH) syndrome with colitis

A previous case report of colitis and serine proteinase 3-antineutrophil cytoplasmic antibody positivity in pyogenic arthritis, pyoderma gangrenosum (PG), acne and hidradenitis suppurativa (PAPASH) syndrome with colitis has been published. Herein, we report a similar case of myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA) positivity. A 26-year-old man presented with recurrent aseptic pyogenic arthritis, acne, hidradenitis suppurativa and PG. Lower gastrointestinal endoscopy was performed, and colitis was observed. No PSTPIP1 gene mutation was found in the gene-sequencing test. Based on these findings and prior case reports, we diagnosed the patient with PAPASH syndrome, a PAPA spectrum disorder complicated by colitis. This patient had PAPASH syndrome with colitis and was MPO-ANCA and anticardiolipin antibodies-positive; it is unclear whether these antibodies play a role in this disease, but it may provide clues to further elucidate its pathogenesis.

Lower soluble Klotho levels in the pretransplant period are associated with an increased risk of renal function decline in renal transplant patients

Serum soluble Klotho levels are associated with renal function in predialysis patients with chronic kidney disease. However, few reports exist regarding the association between soluble Klotho levels and renal function in kidney transplant (KTx) recipients. This was a retrospective observational study of 41 living KTx recipients. The serum soluble Klotho levels were classed as "high" (>456 pg/mL [i.e., high-Klotho group]) or "low" (≤456 pg/mL [i.e., low-Klotho group]). Renal function decline was defined as a decrease in the estimated glomerular filtration rate (eGFR) of 30% or more from the baseline value within 3 months after KTx. A multivariable time-to-event analysis between the groups was conducted. Among the KTx recipients, the incidence of a 30% decrease in the eGFR was significantly higher in the low-Klotho group than in the high-Klotho group (P = .036). After adjusting for donor age, donor sex, the presence of rejection, and the number of cytomegalovirus infections, multivariable Cox models revealed that low soluble Klotho levels remained associated with a higher risk of a 30% decrease in the eGFR (hazard ratio, 2.38; 95% confidence interval, 1.02-6.41). These findings suggested that lower soluble Klotho levels in the pre-KTx period are associated with an increased risk of renal function decline in KTx recipients.

Early response of the parathyroid gland to withdrawal of a calcimimetic compound in uremic rats

Little is known about changes in parathyroid cells when calcimimetics are withdrawn. We examined the response of parathyroid glands to cinacalcet (Cina) withdrawal in uremic Sprague-Dawley rats fed a high-phosphate diet to develop secondary hyperparathyroidism and divided into groups treated with vehicle (UC), Cina, and Cina and maxacalcitol (Maxa), a vitamin D receptor activator (CiNa + Maxa). After 2 wk of treatment, vehicle and Cina were withdrawn and Maxa was continued. Rats were analyzed immediately (day 0) and 7 days (day 7) after withdrawal. The Cina and CiNa + Maxa groups had significantly lower parathyroid hormone (PTH) than the UC group on day 0, although PTH in the Cina group reached UC levels on day 7. On day 0, there were significantly more proliferating cell nuclear antigen-positive cells in the UC group compared with normal controls, and this increase was significantly suppressed in the Cina and CiNa + Maxa groups. On day 7, the Cina group, but not the CiNa + Maxa group, showed a significant increase in proliferating cell nuclear antigen-positive cells compared with the UC group. This increase was related to parathyroid cell diameter regression to UC levels, whereas combination treatment maintained diameter suppression. These results indicate that parathyroid growth activity is stimulated by Cina withdrawal, although the PTH level was not further increased. Continuous administration of Cina may be required for optimal control of secondary hyperparathyroidism, and simultaneous use of a vitamin D receptor activator may be advisable during Cina withdrawal.

Disseminated Intravascular Coagulation-like Reaction after Rituximab Infusion in a Patient with Nephrotic Syndrome

Several case series have suggested that rituximab is efficacious in adult patients with minimal change disease. We herein report a case of disseminated intravascular coagulation-like reaction after rituximab infusion in a patient with nephrotic syndrome. A 58-year-old Japanese man with minimal change disease diagnosed 15 years earlier was started on rituximab to prevent relapse of nephrotic syndrome when he presented to our clinic with low albuminemia, massive proteinuria, and leg edema. Eleven days after rituximab infusion, he presented with abdominal pain, appetite loss, and tarry stool. A laboratory examination revealed severe thrombocytopenia and coagulopathy, and upper gastrointestinal endoscopy revealed multiple hemorrhagic ulcers in his esophagus and stomach. The patient died two days later. Physicians should consider disseminated intravascular coagulation-like reaction when encountering cases with thrombocytopenia after rituximab infusion for any disease.

External validation of the quick Sequential Organ Failure Assessment score for mortality and bacteraemia risk evaluation in Japanese patients undergoing haemodialysis: a retrospective multicentre cohort study

OBJECTIVES

We aimed to examine the validity of the quick Sequential Organ Failure Assessment (qSOFA) score for mortality and bacteraemia risk assessment in Japanese haemodialysis patients.

DESIGN

This is a retrospective multicentre cohort study.

SETTING

The six participating hospitals are tertiary-care institutions that receive patients on an emergency basis and provide primary, secondary and tertiary care. The other participating hospital is a secondary-care institution that receives patients on an emergency basis and provides both primary and secondary care.

PARTICIPANTS

This study included haemodialysis outpatients admitted for bacteraemia suspicion, who had blood drawn for cultures within 48 hours of their initial admission.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome measure was overall in-hospital mortality. Secondary outcomes included 28-day in-hospital mortality and the incidence of bacteraemia diagnosed based on blood culture findings. The discrimination, calibration and test performance of the qSOFA score were assessed. Missing data were handled using multiple imputation.

RESULTS

Among the 507 haemodialysis patients admitted with bacteraemia suspicion between August 2011 and July 2013, the overall in-hospital mortality was 14.6% (74/507), the 28-day in-hospital mortality was 11.1% (56/507) and the incidence of bacteraemia, defined as a positive blood culture, was 13.4% (68/507). For predicting in-hospital mortality among haemodialysis patients, the area under the receiver operating characteristic curve was 0.61 (95% CI 0.56-0.67) for a qSOFA score ≥2. The Hosmer-Lemeshow χ² statistics for the qSOFA score as a predictor of overall and 28-day in-hospital mortality were 5.72 (p=0.02) and 7.40 (p<0.01), respectively.

CONCLUSION

On external validation, the qSOFA score exhibited low diagnostic accuracy and miscalibration for in-hospital mortality and bacteraemia among haemodialysis patients.

The association of the difference in hemoglobin levels before and after hemodialysis with the risk of 1-year mortality in patients undergoing hemodialysis. Results from a nationwide cohort study of the Japanese Renal Data Registry

Background

Few clinical studies have directly examined the associations of hemoglobin (Hb) levels after hemodialysis (HD) and of the difference in Hb levels before and after HD (ΔHb) with patient outcomes. The present study aimed to determine ΔHb and post-HD Hb levels with nationwide data and to examine their associations with all-cause mortality in patients undergoing HD.

Methods

This study is based on data from 2008 and 2009 recorded in the Japanese Renal Data Registry. Study endpoints were all-cause mortality within 1-year. The ΔHb and post-HD Hb level as categorical variables using Cox regression for 1-year mortality, adjusting for potential confounders.

Results

The median ΔHb was 1.0 g/dl, and the post-HD Hb level was 11.3 g/d. The median pre-HD Hb level was 10.4 g/dl. The risk of mortality was lower with a ΔHb of 0 to 1.0 g/dl (adjusted hazard ratio [aHR], 0.90; 95% confidence interval [CI], 0.70–1.01) or > 1.0 g/dl (aHR, 0.73; 95% CI, 0.64–0.84) than with a ΔHb < 0 g/dl. The risk for mortality was also lower with a post-HD Hb of 10 to 11 g/dl (aHR, 0.82; 95% CI, 0.73–0.92), 11 to 12 g/dl (aHR, 0.77; 95% CI, 0.68–0.87), or > 12 g/dl (aHR, 0.77; 95% CI, 0.68–0.87) than with a post-HD Hb < 10 g/dl.

Conclusions

Both a low ΔHb and a low post-HD Hb level were associated with a higher risk of 1-year mortality.

Secondary Hyperparathyroidism: Pathogenesis and Latest Treatment

The classic pathogenesis of secondary hyperparathyroidism (SHPT) began with the trade-off hypothesis based on parathyroid hormone hypersecretion brought about by renal failure resulting from a physiological response to correct metabolic disorder of calcium, phosphorus, and vitamin D. In dialysis patients with failed renal function, physiological mineral balance control by parathyroid hormone through the kidney fails and hyperparathyroidism progresses. In this process, many significant genetic findings have been established. Abnormalities of Ca-sensing receptor and vitamin D receptor are associated with the pathogenesis of SHPT, and fibroblast growth factor 23 has also been shown to be involved in the pathogenesis. Vitamin D receptor activators (VDRAs) are widely used for treatment of SHPT. However, VDRAs have calcemic and phosphatemic effects that limit their use to a subset of patients, and calcimimetics have been developed as alternative drugs for SHPT. Hyperphosphatemia also affects progression of SHPT, and control of hyperphosphatemia is, therefore, thought to be fundamental for control of SHPT. Currently, a combination of a VDRA and a calcimimetic is recognized as the optimal strategy for SHPT, and for other outcomes such as reduced cardiovascular disease and improved survival. The latest findings on the pathogenesis and treatment of SHPT are summarized in this review.

Truncal Adiposity Influences High-Density Lipoprotein Cholesterol Levels and Cardiovascular Events in Hemodialysis Patients

OBJECTIVE

Adiposity influences lipid metabolism and atherosclerotic cardiovascular disease (CVD) in the general population. The aim of the present study was to assess the association between fat mass (FM) and lipid metabolism and CVD events among patients on hemodialysis (HD).

METHODS

This prospective observational study examined 240 patients on prevalent HD. Blood samples were obtained before dialysis at baseline to measure lipids, high-sensitivity C-reactive protein (hs-CRP), interleukin-6, and adiponectin. Lipids and hs-CRP were measured every 3 months for 12 months. FM was estimated by dual energy x-ray absorptiometric scan at baseline and 12 months later. Patients were then prospectively followed up for 36 months after the 1-year measurement period, and composite CVD events were estimated.

RESULTS

Truncal FM was positively correlated with body mass index, hs-CRP, interleukin-6, total cholesterol, low-density lipoprotein-C, triglyceride, and negatively correlated with high-density lipoprotein (HDL)-C and adiponectin at baseline. HDL-C levels were repeatedly decreased, and triglyceride and non-HDL-C were serially increased in the patient group with truncal FM > 7,000 g at both baseline and 12 months (large truncal FM group) compared with the other groups. Cox proportional hazards models adjusted for confounders showed composite CVD events occurred significantly in patients with large truncal FM and continuous low HDL-C levels.

CONCLUSIONS

Truncal adiposity influences lipid metabolism in patients on HD, and the prevalence of CVD events may be increased in those patients with high fat and lipid abnormalities, especially continuously low HDL-C levels.

Effect of Continuous Intravenous Calcium Loading on Fibroblast Growth Factor 23 in Normal and Uremic Rats

Fibroblast growth factor 23 (FGF23) is associated with mortality in patients with CKD. However, the mechanisms underlying stimulation of FGF23 remain to be investigated. We examined whether hypercalcemia induced by continuous intravenous (CIV) calcium (Ca) infusion regulates FGF23 levels in normal rats (Normal) and 5/6 nephrectomized uremic rats (Nx). Microinfusion pumps were implanted in the Normal and Nx rats for CIV Ca infusion, and blood, urine, kidney, and tibia were collected. The results showed an increase in serum Ca-stimulated FGF23 independently of serum phosphate (P) and creatinine levels in Normal and Nx rats. FGF23 mRNA from the tibia was also increased by the Ca infusion. Despite high FGF23 levels after Ca infusion, urinary P excretion was decreased. Renal α-Klotho expression was significantly reduced by Ca infusion. These results suggest that intravenous Ca loading might stimulate FGF23 production from bone in normal and uremic rats. Reduction of renal P excretion suggests that the bioactivity of FGF23 is inhibited, and the decrease in renal α-Klotho expression might have a role in this pathological process. In conclusion, CIV Ca loading increased FGF23 in normal and uremic rats, and renal α-Klotho is necessary to maintain the bioactivity of FGF23 as a phosphaturic factor.

Evaluation of changes in ferritin levels during sucroferric oxyhydroxide treatment

Background

A sub-analysis of a Phase III study was conducted to identify factors that might predict increased ferritin levels during long-term sucroferric oxyhydroxide (SO) treatment in hemodialysis patients.

Methods

The open-label, multicenter, Phase III study assessed the efficacy and safety of SO 750–3000 mg/day for 52 weeks in Japanese patients with chronic renal failure and hyperphosphatemia. A total of 125 of 161 patients from the Phase III trial, and who had data for ferritin levels after 28 weeks of SO treatment, were evaluated.

Results

Baseline ferritin was the strongest contributor (P < 0.0001) to ferritin increases during SO treatment. By Week 28, there were significant differences (P < 0.05/3) in ferritin increases between patients with higher [quartile 4 (Q4)] versus lower (Q1, Q2 and Q3) baseline ferritin. An erythropoiesis-stimulating agent dosage reduction was observed in patients with the lowest baseline ferritin level (Q1), and only slight reductions were noted in the other patient subsets. SO dosages administered to patients in baseline ferritin quartiles Q2, Q3 and Q4 were comparable throughout the study with slight fluctuations. SO dosages in Q1 were considerably lower than those in the other quartiles.

Conclusions

In summary, of the baseline variables found to predict increased ferritin, and changes in iron-related parameters, during SO treatment in Japanese chronic kidney disease patients undergoing hemodialysis, baseline ferritin was the most relevant variable.

Anemia in conventional hemodialysis: Finding the optimal treatment balance

Renal anemia is a serious and common complication in hemodialysis (HD) patients. The introduction of erythropoiesis-stimulating agents (ESAs) has dramatically improved hemoglobin levels and outcomes. Several interventional studies reported that excessive correction of anemia and the massive use of ESA can trigger cardiovascular disease (CVD), and consequently may worsen the prognosis of patients undergoing HD. Therefore, it has been widely recognized that large doses of ESA should be used with caution. An effective use of iron preparations is required to yield the optimal effect of ESA. It is well-known that iron utilization is inhibited under pathological conditions, such as chronic inflammation, resulting in ESA resistance. It is postulated that a new class of therapeutic agents for renal anemia, hypoxia inducible factor prolyl hydroxylase (HIF-PH) inhibitors, will have beneficial treatment effects in patients on HD. HIF is induced by hypoxia and promotes erythropoietin production. In the absence of a hypoxic state, HIF is decomposed by the HIF catabolic enzyme. HIF-PH inhibitors inhibit this degrading enzyme and stimulate endogenous erythropoietin production via HIF induction. Additionally, HIF-PH inhibitors promote effective utilization of iron and raise erythropoietin to physiological concentrations. Accordingly, HIF-PH inhibitors improve anemia and iron metabolism. It appears that this effect persists irrespective of chronic inflammatory conditions. HIF-PH inhibitors do not overshoot erythropoietin above physiological concentrations like ESAs. Therefore, it is hypothesized that HIF-PH inhibitors would not increase the risk of CVD in patients undergoing HD.

A mutation in transcription factor MAFB causes Focal Segmental Glomerulosclerosis with Duane Retraction Syndrome

Focal segmental glomerulosclerosis (FSGS) is a leading cause of end-stage renal disease in children and adults. Genetic factors significantly contribute to early-onset FSGS, but the etiologies of most adult cases remain unknown. Genetic studies of monogenic syndromic FSGS exhibiting extra-renal manifestations have uncovered an unexpected biological role for genes in the development of both podocytes and other cellular lineages. To help define these roles, we studied two unrelated families with FSGS associated with Duane Retraction Syndrome, characterized by impaired horizontal eye movement due to cranial nerve malformation. All four affected individuals developed FSGS and Duane Retraction Syndrome in their first to second decade of life, manifested as restricted abduction together with globe retraction and narrowed palpebral fissure on attempted adduction. Hypoplasia of the abducens nerves and hearing impairment occurred in severely affected individuals. Genetic analyses revealed that affected individuals harbor a rare heterozygous substitution (p.Leu239Pro) in MAFB, a leucine zipper transcription factor. Luciferase assays with cultured monocytes indicated that the substitution significantly reduced transactivation of the F4/80 promoter, the known MAFB recognition element. Additionally, immunohistochemistry indicated reduced MAFB expression in the podocytes of patients. Structural modeling suggested that the p.Leu239Pro substitution in the DNA-binding domain possibly interferes with the stability of the adjacent zinc finger. Lastly, podocytes in neonatal mice with p.Leu239Pro displayed impaired differentiation. Thus, MAFB mutations impair development and/or maintenance of podocytes, abducens neurons and the inner ear. The interactions between MAFB and regulatory elements in these developing organs are likely highly specific based on spatiotemporal requirements.

Practice pattern of physician's directions of exercise restriction in patients with chronic kidney disease: results from the Chronic Kidney Disease Japan Cohort study

Background

The practice patterns of exercise restrictions for patients with chronic kidney disease have not been adequately evaluated yet; thus, we examined them using a cross-sectional design and explored the factors related with those restrictions.

Methods

The Chronic Kidney Disease Japan Cohort study was a multicentre cohort study of Japanese patients (age 20–75 years) living in Japan. We used the information in the questionnaire on the restriction of physical activities offered by physicians to the patients during enrolment. We initially considered and used the following data as the clinical factors that the physician used for decision making on the directions of restriction of physical activities: age, sex, cause of chronic kidney disease (CKD), comorbid diseases, body mass index (BMI), systolic blood pressure, estimated glomerular filtration rate (eGFR) and urine albumin. The logistic regression model was used to explore the factors and estimate their adjusted odds ratio with regard to physician’s direction of restriction of physical activities.

Results

Physician’s direction of exercise restrictions was implemented in 9.9% of the participants. In 17 facilities, the proportion of physician’s direction of exercise restriction ranged from 2.9 to 17.8%. The logistic regression analysis showed that the proportion of the factors such as younger age, cardiovascular disease, congestive heart failure and lower eGFR was higher in patients with physician’s direction of exercise restrictions.

Conclusions

The findings from this study suggested the factors related with prescribing exercise restrictions. Further studies examining which patients with CKD need direction of exercise restrictions are needed.

Efficacy and Safety of Sucroferric Oxyhydroxide and Calcium Carbonate in Hemodialysis Patients

INTRODUCTION

In this phase III, open-label, single-arm, multi-center 12-week study, we evaluated the efficacy and safety of combination therapy with sucroferric oxyhydroxide (PA21) and calcium carbonate for hemodialysis patients with hyperphosphatemia.

METHODS

We enrolled 35 subjects aged ≥ 20 years with end-stage kidney disease and serum phosphorus 3.5-6.0 mg/dl who were undergoing hemodialysis 3 times weekly and taking calcium carbonate and sevelamer hydrochloride. Patients switched from sevelamer hydrochloride and calcium carbonate to sucroferric oxyhydroxide and calcium carbonate. Sucroferric oxyhydroxide was orally administered 3 times daily within 750 mg/d (250 mg per dose) to 3000 mg/d (1000 mg per dose), immediately before every meal, for 12 weeks. Calcium carbonate was orally administered 3 times daily after every meal. Outcomes were serum phosphorus concentration, safety, and satisfaction with bowel movements.

RESULTS

Mean (SD) serum phosphorus concentrations were 5.01 (0.63) mg/dl at week 0 and 4.89 (1.14) mg/dl at the end of treatment, after patients switched from sevelamer hydrochloride to sucroferric oxyhydroxide. The incidence of adverse drug reactions was 31.4% (11/35), with diarrhea being the most frequent (31.4%). More sucroferric oxyhydroxide-treated patients were satisfied with their bowel movements. More patients with constipation, as well as those who experienced diarrhea, were satisfied with their bowel movements at the end of the study.

CONCLUSION

Combined administration of sucroferric oxyhydroxide and calcium carbonate at low doses was effective in maintaining serum phosphorus concentrations within the target range, and patients' gastrointestinal status improved. Sucroferric oxyhydroxide maintained its serum phosphorus-lowering effect with a decreased pill burden, and its concomitant administration with calcium carbonate was well tolerated.

Efficacy and safety of sucroferric oxyhydroxide compared with sevelamer hydrochloride in Japanese haemodialysis patients with hyperphosphataemia: A randomized, open-label, multicentre, 12-week phase III study

Aim

We aimed to investigate the non‐inferiority of PA21 (sucroferric oxyhydroxide) to sevelamer hydrochloride (sevelamer) in terms of efficacy and safety in Japanese haemodialysis patients with hyperphosphataemia.

Methods

In this Phase III, open‐label, multicentre study, 213 haemodialysis patients with hyperphosphataemia were randomized to PA21 or sevelamer treatment for 12 weeks. The primary outcome was adjusted serum phosphorus concentration at the end of treatment; the non‐inferiority of PA21 was confirmed if the upper limit of the two‐sided 95% confidence interval (CI) is ≤0.32 mmol/L. Secondary outcomes were corrected serum calcium and intact‐parathyroid hormone concentrations. Adverse events (AEs) and adverse drug reactions (ADRs) were evaluated.

Results

The adjusted mean serum phosphorus concentration at the end of treatment confirmed the non‐inferiority of PA21 for lowering serum phosphorus compared with sevelamer (1.62 vs 1.72 mmol/L; difference, −0.11 mmol/L; 95% CI, −0.20 to −0.02 mmol/L). The mean daily tablet intake was 5.6 ± 2.6 and 18.7 ± 7.1 tablets in the PA21 and sevelamer groups, respectively. The incidences of AEs and ADRs were not significantly different between the two groups.

Conclusion

The non‐inferiority of PA21 to sevelamer was confirmed for the treatment of Japanese haemodialysis patients with hyperphosphataemia. PA21 was effective, safe, and well tolerated, while having a considerably lower pill burden than sevelamer.

This short‐term randomized trial of PA21 (sucroferric oxyhydroxide) performed in Japanese haemodialysis patients was able to demonstrate non‐inferiority for phosphorus lowering with a significantly lower pill burden.

Management of phosphorus load in CKD patients

Disturbances in mineral and bone metabolism play a critical role in the pathogenesis of cardiovascular complications in patients with chronic kidney disease (CKD). The term "renal osteodystrophy" has recently been replaced with "CKD-mineral and bone disorder (CKD-MBD)", which includes vascular calcification as well as bone abnormalities. In Japan, proportions of the aged and long-term dialysis patients are increasing which makes management of vascular calcification and parathyroid function increasingly more important. There are three main strategies to manage phosphate load: phosphorus dietary restriction, administration of phosphate binder and to ensure in the CKD 5D setting, an adequate dialysis.

Cardiac effect of vitamin D receptor modulators in uremic rats

Vitamin D receptor (VDR) modulators (VDRMs) are commonly used to control secondary hyperparathyroidism (SHPT) associated with chronic kidney disease, and are associated with beneficial outcomes in cardiovascular disease. In this study, we compared the cardiac effect of VS-105, a novel VDRM, with that of paricalcitol in 5/6 nephrectomized uremic rats. Male Sprague-Dawley rats were 5/6 nephrectomized, fed a standard diet for 4 weeks to establish uremia, and then treated (intraperitoneally, 3 times/week) with vehicle (propylene glycol), paricalcitol (0.025 and 0.15μg/kg), or VS-105 (0.05 and 0.3μg/kg) for 4 weeks. In uremic rats, neither VDRM (low and high doses) altered serum creatinine and phosphorus levels. Serum calcium was significantly higher with high dose paricalcitol compared to sham rats. PTH levels were significantly decreased with low dose paricalcitol and VS-105, and were further reduced in the high dose groups. Interestingly, serum FGF23 was significantly higher with high dose paricalcitol compared to sham rats, whereas VS-105 had no significant effect on FGF23 levels. Left ventricle (LV) weight and LV mass index determined by echocardiography were significantly suppressed in both high dose VDRM groups. This suppression was more evident with VS-105. Western blotting showed significant decreases in a fibrosis marker TGF-β1 in both high dose VDRM groups (vs. vehicle) and Masson trichrome staining showed significant decreases in cardiac fibrosis in these groups. These results suggest that VS-105 is less hypercalcemic than paricalcitol and has favorable effects on SHPT and cardiac parameters that are similar to those of paricalcitol in uremic rats. The cardioprotective effect is a noteworthy characteristic of VS-105.

Dose-response efficacy and safety of PA21 in Japanese hemodialysis patients with hyperphosphatemia: a randomized, placebo-controlled, double-blind, Phase II study

Background

Hyperphosphatemia is common in chronic kidney disease (CKD) and associated with mortality and morbidity. We aimed to evaluate the dose-dependent efficacy and safety of PA21 (sucroferric oxyhydroxide), an iron-based phosphate binder, in Japanese hemodialysis patients with hyperphosphatemia.

Methods

In this double-blind, multicenter, Phase II study, 183 patients were randomized to placebo or PA21 at doses of 250, 500, 750, or 1000 mg (based on iron content) three times/day for 6 weeks. The primary efficacy endpoint was the mean change in serum phosphorus levels from baseline to end of treatment in each group. Adverse reactions were evaluated.

Results

The change in serum phosphorus level was significantly greater in each PA21 group than in the placebo group (analysis of covariance: P < 0.001 for all groups). A dose-dependent change in serum phosphorus levels was observed in the PA21 groups. A notable decrease in mean serum phosphorus levels to the target level of ≤6 mg/dL was shown starting at Week 1 in all PA21 groups. The cumulative achievement rates for target serum phosphorus level at the end of treatment were generally >80 % in all PA21 groups. The major adverse reaction reported was diarrhea; however, most cases were mild.

Conclusions

PA21 was an effective and safe treatment that decreased serum phosphorus levels starting at 1 week of treatment when administered as one 250-mg tablet three times/day. PA21 demonstrated a dose-dependent phosphorus lowering effect up to 3000 mg/day. PA21 may be a new treatment alternative with relatively low pill burden for Japanese hemodialysis patients with hyperphosphatemia.

Clinical Expectation of Online Hemodiafiltration: A Japanese Perspective

Many pieces of evidence of online hemodiafiltration (HDF) have been reported, and the clinical advantage of postdilution online HDF with sufficient substitution is now established. After the approval of online HDF in 2012, the number of online HDF patients has been dramatically increasing in Japan and reached 10% of the total dialysis population at the end of 2013. One of the marked characteristics of Japanese online HDF is a widespread use of predilution treatment and, in 2013, 90.8% of online HDFs were carried out with the predilution mode. The main reason for the wide use of predilution online HDF results from the low blood flow rate in Japan, by which it is difficult to substitute a sufficient volume during the limited treatment time. Other reasons to choose the predilution mode include the reduction of albumin loss and the suppression of membrane fouling during treatment. Contrary to postdilution treatment, adequate clinical evidence has not been reported for predilution online HDF to provide a better outcome of the patients. A further clinical trial is expected to elucidate the clinical advantages over conventional hemodialysis for predilution online HDF.

Possible prevention of dialysis-requiring congestive heart failure by angiotensin-II receptor blockers in non-dialysis Japanese patients with Stage 5 chronic kidney disease

BACKGROUND

Preventive medications for dialysis-requiring congestive heart failure (CHF) in non-dialysis Japanese patients with Stage 5 chronic kidney disease (CKD) are unknown. Our aim was to explore which CKD medication was associated with a reduced prevalence of dialysis-requiring CHF in non-dialysis Japanese patients with Stage 5 CKD.

METHODS

The present multicenter, retrospective, cross-sectional study examined the association between CKD medications and the prevalence of dialysis-requiring CHF in non-dialysis Japanese patients with Stage 5 CKD.

RESULTS

There were 1536 Japanese Stage 5 CKD patients who satisfied our inclusion criteria. We had 309 (20.1%) patients whom had developed dialysis-requiring CHF and 940 patients (60.8%) whom had been using angiotensin-II receptor blockers (ARBs) before initiating dialysis. In our multivariate analysis, only ARB use was significantly associated with a lower risk of CHF (Odds ratio (OR): 0.680, 95% confidence interval (CI): 0.516-0.897; p = 0.0064), of the CKD treatments examined in this study.

CONCLUSIONS

We found that ARB use during the pre-dialysis period is associated with a lower prevalence of CHF in the non-dialysis Japanese patients with Stage 5 CKD, suggesting a possible prevention of dialysis-requiring CHF by ARBs, in non-dialysis Japanese patients with Stage 5 CKD.

Indication and efficacy of PEIT in the management of secondary hyperparathyroidism

Control of secondary hyperparathyroidism (SHPT) using active vitamin D analogues becomes difficult in advanced SHPT, because the enlarged parathyroid glands (PTGs) are resistant to medical therapy. Percutaneous ethanol injection therapy (PEIT) has been widely used in Japan since the 1990s as a surgical intervention for advanced SHPT, by selectively destroying only the enlarged glands with nodular hyperplasia (i.e. >0.5 cm(3), measured by ultrasonography). If there is only one PTG with nodular hyperplasia, PEIT will be successful with a small number of injections, and it then becomes possible to maintain target levels of parathyroid hormone by treatment with active vitamin D analogues. Recent studies have demonstrated that in the advanced phase of SHPT, it is desirable to perform PEIT when it is restricted to patients with not more than one PTG larger than 0.5 cm(3) in terms of superior prognosis can be obtained including efficacy, low recurrence, and long-term remission period.

Long-term prognosis of parathyroid function in chronic dialysis patients after PEIT-a single-centre trial

Background. Secondary hyperparathyroidism (SHPT) is a common complication observed in long-term dialysis patients. Percutaneous ethanol injection therapy (PEIT) of parathyroid glands (PTGs) is now established in Japan as a treatment option for SHPT. In this study, to elucidate the factors influencing efficacy in 1 year and relapse following PEIT, we analysed the long-term prognosis of parathyroid function that is known to have the greatest effect on therapeutic results.

Methods. The study design was a retrospective cohort study. We studied 104 patients with SHPT, who underwent PEIT at Tokai University Hospital between January 1993 and December 2002, and we followed them up until January 2008. The effective group reached intact parathyroid hormone of 200 pg/ml or less, corrected calcium (Ca) of 10.5 mg/dl or less and phosphate (P) of 6.0 mg/dl or less. The ineffective group failed to achieve these criteria.

Results. Among the 104 patients, 66 patients (63%) fulfilled the criteria for the effective group within the first year of PEIT. Using the multivariate logistic regression analysis, the number of PTGs before PEIT was a significant risk factor to deviate from the criteria. At the end of the surveillance period, 31 patients (30%) fulfilled the criteria, and their SHPT was controlled with PEIT. Using the multivariate logistic regression analysis, more than three PTGs at the beginning, and the increase in PTGs during the observation period were significant risk factors to deviate from the criteria. In conclusion, superior results with PEIT are obtained in terms of efficacy, remission period and risk of relapse, regardless of the size of the gland.

Clinical significance of parathyroid intervention on CKD-MBD management

Recently published ‘Guidelines for the management of secondary hyperparathyroidism in chronic dialysis patients’ by the Japanese Society for Dialysis Therapy advocate that percutaneous ethanol injection into enlarged glands, which has been considered as the only alternative to parathyroidectomy (PTx), should be indicated in patients with a single enlarged parathyroid gland (estimated volume >500 mm³, or estimated major axis >10 mm), and that PTx should be recommended in patients with multiple enlarged glands. Cinacalcet cannot achieve optimal control of chronic kidney disease–mineral bone disorder in all patients, and parathyroid intervention will be required in a considerable number of patients with refractory secondary hyperparathyroidism.

New clinical guidelines for selective direct injection therapy of the parathyroid glands in chronic dialysis patients

In 2000, the Japanese Society for Parathyroid Intervention issued the 'Guidelines for percutaneous ethanol injection therapy of the parathyroid glands in chronic dialysis patients'. Since then, the concept of 'selective PEIT' has been well accepted and the number of patients treated by this method in Japan has increased. Recently, it has been reported that the effect of PEIT differs depending on the degree of nodular hyperplasia. Several new drugs have become available since 2000, and active vitamin D and its analogue have also been used for direct injection into the parathyroids. We present the new 'Guidelines for selective direct injection therapy of the parathyroid glands in chronic dialysis patients', a revised version of the 2000 Guidelines. We believe that these new guidelines are useful for selecting direct injection therapy in patients with advanced secondary hyperparathyroidism.

Absence of mesangial C1q deposition is associated with resolution of proteinuria and hematuria after tonsillectomy plus steroid pulse therapy for immunoglobulin a nephropathy

INTRODUCTION AND AIMS

Deposition of C1q occurs in 0 to 45% of patients with IgAN. In order to identify whether mesangial C1q deposition in IgAN is a novel marker for the response to tonsillectomy plus steroid pulse therapy (TSP), we studied the association between mesangial C1q deposition in IgAN and the remission rate after TSP therapy for IgAN.

METHODS

We conducted a retrospective cohort study at a single Japanese center. We analyzed data on 110 patients diagnosed with IgA nephropathy who received TSP between January 2003 and December 2012. Positive C1q findings were defined as diffuse mesangial C1q deposition. The study outcome was the resolution of abnormal urinary findings and was defined as negative proteinuria and negative occult blood 1 year after steroid pulse therapy.

RESULTS

In all enrolled cases, 69 patients (62.7%) went into remission. Ten out of 24 (41.7%) C1q-positive patients experienced remission, and 59 out of 86 (68.6%) C1q-negative patients experienced remission. Multiple logistic regression model analysis showed that the absence of C1q deposition increased the odds ratio for remission (odds ratio 4.41; 95% confidence interval 1.33-15.75, p = 0.017).

CONCLUSIONS

These results suggest that the absence of diffuse C1q deposition in the mesangial area of the glomerulus in patients with IgA nephropathy is a positive predictive sign for a response to TSP and is associated with the resolution of urinary abnormalities 1 year after TSP.

Association between the Hemoglobin Level and Cardiothoracic Ratio in Patients on Incident Dialysis

BACKGROUND/AIM

The present study explores associations between hemoglobin (Hb) levels and patients with cardiac enlargement in end-stage kidney disease (ESKD) to help prevent cardiac remodeling during the predialysis phase of chronic kidney disease (CKD).

METHODS

This cross-sectional study included 2,249 patients with ESKD (age, 67 ± 13 years; male, 67%; diabetic kidney disease, 41%) who started hemodialysis (HD) between January 2006 and October 2013 at eight participating hospitals. We examined associations between Hb levels immediately before the first HD session and cardiothoracic ratios (CTRs). Clinical factors associated with the CTR were also assessed.

RESULTS

The mean Hb level was 8.7 ± 1.6 g/dl, and the mean and median CTRs were 55.0 and 54.7%, respectively. The correlation between the Hb level and the CTR was linear and negative (r = -0.129, p < 0.001). The mean CTR and the prevalence of patients with a CTR >50% obviously decreased with increasing Hb levels (both p < 0.001 for trend). Univariate logistic regression analysis revealed an approximately 20% reduction in the odds ratio for complicating CTRs >50% per 1 g/dl increase in Hb. Hb levels of <9 g/dl were significantly associated with CTRs >50%. Numerical and categorical Hb remained significantly associated with CTRs >50% after adjusting for confounding variables.

CONCLUSIONS

Lower Hb levels participate in progressive CTR enlargement in patients with ESKD, and maintaining Hb levels of >9 g/dl might help prevent cardiac remodeling during the predialysis phase of CKD.

Significance of serum magnesium as an independent correlative factor on the parathyroid hormone level in uremic patients

CONTEXT

PTH is a critical factor in mineral homeostasis, and chronic kidney disease mineral and bone metabolism disorder is a very important problem in patients with renal failure. Abnormal levels of PTH, serum phosphate, and calcium influence chronic kidney disease mineral and bone metabolism disorder, but there is little information about the influence of magnesium (Mg) on PTH.

OBJECTIVE

The aim of this study was to elucidate the correlation between magnesium and PTH levels in uremic patients just prior to beginning hemodialysis (HD) for the first time.

PATIENTS

We enrolled 1231 patients in nine Japanese facilities who had begun HD for end-stage renal disease. We investigated their serum Mg levels and the correlation between intact PTH (iPTH) and the serum Mg levels and other clinical parameters and medications.

RESULTS

The mean serum Mg was 2.2 ± 0.5 mg/dL, and hypermagnesemia was found in 663 patients (53.9%). Divided into two groups according to median iPTH level, the serum Mg levels were significantly higher in patients with low iPTH (2.3 ± 0.5 vs 2.1 ± 0.5, P < .01). Furthermore, divided into two groups according to the Mg level, iPTH levels were lower in patients with high Mg than in patients with normal serum Mg levels (277.9 ± 195.9 pg/mL vs 321.9 ± 203.7 pg/mL, P < .01). In the multiple regression analysis according to the effect of iPTH level, the serum Mg level was an independent variable after adjustment for other factors.

CONCLUSIONS

A high serum level of Mg is frequent in uremic patients with end-stage renal disease just prior to beginning HD. In the present set of patients, there was a significant correlation between the serum Mg and iPTH levels. Furthermore, the serum Mg level was an independent factor apart from the other factors regulating iPTH. These results suggest that serum Mg may be one of the factors regulating the serum PTH level in uremic patients.