Protocol for the nationwide registry of patients with polycystic kidney disease: japanese national registry of PKD (JRP).

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) and autosomal recessive polycystic kidney disease (ARPKD) are major genetic polycystic kidney diseases that can progress to end-stage kidney disease (ESKD). Longitudinal data on the clinical characteristics associated with clinical outcomes in polycystic kidney disease (PKD), including the development of ESKD and cardiovascular disease (CVD) are lacking in Japan. To address this unmet need the authors are establishing a novel, web-based, Nationwide Cohort Registry Study-the Japanese Registry of PKD (JRP). METHODS: The JRP is a prospective cohort study for ADPKD (aim to recruit n = 1000 patients), and both a retrospective and prospective study for ARPKD (aim to recruit n = 100). In the prospective registry, patients will be followed-up for 10 years every 6 months and 12 months for patients with ADPKD and ARPKD, respectively. Data collection will be recorded on Research Electronic Data Capture (REDCap) starting on April 1, 2024, with recruitment ending on March 31, 2029. (jRCT 1030230618). RESULTS: Data to be collected include: baseline data, demographics, diagnostic and genetic information, radiological and laboratory findings, and therapeutic interventions. During follow-up, clinical events such as development of ESKD, hospitalization, occurrence of extra kidney complications including CVD events, and death will be recorded, as well as patient-reported health-related quality of life for patients with ADPKD. CONCLUSIONS: The JRP is the first nationwide registry study for patients with ADPKD and ARPKD in Japan, providing researchers with opportunities to advance knowledge and treatments for ADPKD and ARPKD, and to inform disease management and future clinical practice.

[Nationwide Questionnaire Survey on Disaster Power Outage Countermeasures in the Radiology Departments of Hospitals].

PURPOSE: To identify the countermeasures and current status of disaster power outages in the radiology departments of hospitals. METHODS: A web-based questionnaire survey of 600 hospitals nationwide was conducted. The questionnaire survey covered 34 items, including availability of power in the radiology department in the event of a disaster and the impact of power outages on medical equipment in the radiology department. RESULTS: In all, 242 facilities (40.3%) responded to our survey. During power outages, 55.8%-68.2% of facilities were able to use CT, digital radiography, and angiography systems with their private generators. In 28.1%-40.7% of facilities, medical information systems were not available in all laboratories. In addition, power outages caused equipment malfunctions in 81.4% of facilities' radiology departments. CONCLUSION: We have identified the power supplied by private generators to the radiology department's medical equipment and medical information systems. Many medical equipment have malfunctioned due to power outages. Therefore, drills should be conducted to simulate various situations caused by power outages.

Renal Medullary Angiitis Associated with Cutaneous Leukocytoclastic Vasculitis: A Case Report.

Renal medullary angiitis is characterized by interstitial hemorrhaging in the medulla with neutrophil infiltration. An 81-year-old man presented with a fever, kidney dysfunction, and purpura of the legs, which was diagnosed as leukocytoclastic vasculitis. Proteinase 3 antineutrophil cytoplasmic antibodies were weakly positive. A kidney biopsy showed severe tubulointerstitial hemorrhaging with neutrophilic infiltration in the perivascular areas surrounding the vasa recta in the medulla without crescent formation in the glomeruli. An immunofluorescence analysis was negative, and electron microscopy revealed no immune-dense deposits, ruling out immunoglobulin A vasculitis. Intravenous methylprednisolone for three days and plasma exchange followed by oral prednisolone improved his general condition.

Public support for patients with intractable diseases in Japan: impact on clinical indicators from nationwide registries in patients with autosomal dominant polycystic kidney disease.

BACKGROUND: Clinical practice guidelines recommend antihypertensive and tolvaptan therapies for patients with autosomal dominant polycystic kidney disease (ADPKD) in Japan. However, tolvaptan therapy may pose an economic burden. The Japanese Ministry of Health, Labour and Welfare supports patients with intractable diseases. This study aimed to confirm the impact of the intractable disease system in Japan on the clinical treatment of ADPKD. METHODS: We analyzed the data of 3768 patients with ADPKD having a medical subsidy certificate from the Japanese Ministry of Health, Labour and Welfare in 2015-2016. The following quality indicators were use: the adherence rate to the 2014 clinical practice guideline for polycystic kidney disease (prescription rates of antihypertensive agents and tolvaptan in this cohort) and the number of Japanese patients with ADPKD nationwide started on renal replacement therapy in 2014 and 2020. RESULTS: Compared with new applications from 2015 to 2016, the prescription rates of antihypertensives and tolvaptan for the indicated patients at the 2017 renewal application increased by 2.0% (odds ratio = 1.41, p = 0.008) and 47.4% (odds ratio = 10.1, p > 0.001), respectively. These quality indicators improved with antihypertensive treatment, especially in patients with chronic kidney disease stages 1-2 (odds ratio = 1.79, p = 0.013) and in those aged < 50 years (odds ratio = 1.70, p = 0.003). The number of patients with ADPKD who were started on renal replacement therapy in Japan decreased from 999 in 2014 to 884 in 2020 in the nationwide database (odds ratio = 0.83, p < 0.001). CONCLUSIONS: The Japanese public intractable disease support system contributes to improvement of ADPKD treatment.

Mutation Analysis of Autosomal-Dominant Polycystic Kidney Disease Patients.

Autosomal-dominant polycystic kidney disease (ADPKD) is characterized by bilateral kidney cysts that ultimately lead to end-stage kidney disease. While the major causative genes of ADPKD are PKD1 and PKD2, other genes are also thought to be involved. Fifty ADPKD patients were analyzed by exome sequencing or multiplex ligation-dependent probe amplification (MLPA), followed by long polymerase chain reaction and Sanger sequencing. Variants in PKD1 or PKD2 or GANAB were detected in 35 patients (70%). Exome sequencing identified 24, 7, and 1 variants in PKD1, PKD2, and GANAB, respectively, in 30 patients. MLPA analyses identified large deletions in PKD1 in three patients and PKD2 in two patients. We searched 90 cyst-associated genes in 15 patients who were negative by exome sequencing and MLPA analyses, and identified 17 rare variants. Four of them were considered "likely pathogenic" or "pathogenic" variants according to the American College of Medical Genetics and Genomics guidelines. Of the 11 patients without a family history, four, two, and four variants were found in PKD1, PKD2, and other genes, respectively, while no causative gene was identified in one patient. While the pathogenicity of each variant in these genes should be carefully assessed, a comprehensive genetic analysis may be useful in cases of atypical ADPKD.

Cystic Kidney Diseases That Require a Differential Diagnosis from Autosomal Dominant Polycystic Kidney Disease (ADPKD).

Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary cystic kidney disease, with patients often having a positive family history that is characterized by a similar phenotype. However, in atypical cases, particularly those in which family history is unclear, a differential diagnosis between ADPKD and other cystic kidney diseases is important. When diagnosing ADPKD, cystic kidney diseases that can easily be excluded using clinical information include: multiple simple renal cysts, acquired cystic kidney disease (ACKD), multilocular renal cyst/multilocular cystic nephroma/polycystic nephroma, multicystic kidney/multicystic dysplastic kidney (MCDK), and unilateral renal cystic disease (URCD). However, there are other cystic kidney diseases that usually require genetic testing, or another means of supplementing clinical information to enable a differential diagnosis of ADPKD. These include autosomal recessive polycystic kidney disease (ARPKD), autosomal dominant tubulointerstitial kidney disease (ADTKD), nephronophthisis (NPH), oral-facial-digital (OFD) syndrome type 1, and neoplastic cystic kidney disease, such as tuberous sclerosis (TSC) and Von Hippel-Lindau (VHL) syndrome. To help physicians evaluate cystic kidney diseases, this article provides a review of cystic kidney diseases for which a differential diagnosis is required for ADPKD.

A nationwide analysis of renal and patient outcomes for adults with lupus nephritis in Japan.

BACKGROUND: The prognosis of lupus nephritis (LN) has improved following the introduction of effective immunosuppressive therapy and progress in supportive care. This study examined recent renal and patient prognosis for adults with LN in Japan. METHODS: We conducted a nationwide retrospective cohort study of LN patients who received a renal biopsy between 2007 and 2012 that were registered in the Japan Renal Biopsy Registry. Of 623 registered adults with LN from 25 institutions and their affiliated or community hospitals, 489 were eligible for this study. RESULTS: The median age at renal biopsy was 39 years, and 82.2% of patients were female. Renal biopsies were performed in 348 patients with new-onset LN, 106 with relapse LN, and 35 with refractory LN. The distribution of ISN/RPS 2003 Classes was as follows: I 1.6%; II 5.3%; III (± V) 27.0%; IV (± V) 47.0%; V 18.4%; VI 0.6%. During the median observation period of 63.8 months, 36 patients (7.3%) reached a doubling of serum creatinine or end-stage kidney disease (ESKD), and 28 patients (5.7%) died. The 5 year renal and patient survival rates were 93.9% and 94.7%, respectively. Multivariate analysis revealed body mass index (BMI) and estimated glomerular filtration rate (eGFR) were independent risk factors for a doubling of serum creatinine in ESKD. Age and eGFR were independent risk factors for death. CONCLUSION: Recent prognosis for adults with LN are relatively good in Japan. Risk factors for impaired renal function are BMI and eGFR at renal biopsy, while age and eGFR are risk factors for death.

Molecular characterization and secreted production of basidiomycetous cell-bound ß-glycosidases applicable to production of galactooligosaccharides.

Cell-bound ß-glycosidases of basidiomycetous yeasts show promise as biocatalysts in galactooligosaccharide (GOS) production. Using degenerated primers designed from Hamamotoa singularis (Hs) bglA gene, we newly identified three genes that encode cell-bound ß-glycosidase from Sirobasidium magnum (Sm), Rhodotorula minuta (Rm), and Sterigmatomyces elviae (Se). These three genes, also named bglA, encoded family 1 glycosyl hydrolases with molecular masses of 67‒77 kDa. The BglA enzymes were approximately 44% identical to the Hs-BglA enzyme and possessed a unique domain at the N-terminus comprising 110 or 210 amino acids. The Sm-, Rm-, and Se-BglA enzymes as well as the Hs-BglA enzyme were successfully produced by recombinant Aspergillus oryzae, and all enzymes were entirely secreted to the supernatants. Furthermore, addition of some nonionic detergents (e.g. 0.4% [v/v] Triton-X) increased the production, especially of the Hs- or Se-BglA enzyme. Out of the BglA enzymes, the Se-BglA enzyme showed remarkable thermostability (∼70°C). Additionally, the Sm- and Se-BglA enzymes had better GOS yields, so there was less residual lactose than in others. Accordingly, the basidiomycetous BglA enzymes produced by recombinant A. oryzae would be applicable to GOS production, and the Se-BglA enzyme appeared to be the most promising enzyme for industrial uses.

Critical roles of a housekeeping sortase of probiotic Bifidobacterium bifidum in bacterium-host cell crosstalk.

Bifidobacterium bifidum YIT 10347 (BF-1) is adhesive in vitro. Here we studied the molecular aspects of the BF-1 adhesion process. We identified and characterized non-adhesive mutants and found that a class E housekeeping sortase was critical for the adhesion to mucin. These mutants were significantly less adhesive to GCIY cells than was the wild type (WT), which protected GCIY cells against acid treatment more than did a non-adhesive mutant. The non-adhesive mutants aberrantly accumulated precursors of putative sortase-dependent proteins (SDPs). Recombinant SDPs bound to mucin. Disruption of the housekeeping sortase influenced expression of SDPs and pilus components. Mutants defective in a pilin or in an SDP showed the same adhesion properties as WT. Therefore, multiple SDPs and pili seem to work cooperatively to achieve adhesion, and the housekeeping sortase is responsible for cell wall anchoring of its substrates to ensure their proper biological function.

A Kidney Transplant Recipient with Recurrent Henoch-Schönlein Purpura Nephritis Successfully Treated with Steroid Pulse Therapy and Epipharyngeal Abrasive Therapy.

There is no specific treatment for recurrent Henoch-Schönlein purpura nephritis (HSPN) in a transplanted kidney. We herein report a case of a kidney transplant recipient with recurrent HSPN that was successfully treated with steroid pulse therapy and epipharyngeal abrasive therapy (EAT). A 39-year-old Japanese man developed HSPN 4 years ago and had to start hemodialysis after 2 months despite receiving steroid pulse therapy followed by oral prednisolone, plasma exchange therapy, and cyclophosphamide pulse therapy. He had undergone tonsillectomy 3 years earlier in the hopes of achieving a better outcome of a planned kidney transplantation and received a living-donor kidney transplantation from his mother 1 year earlier. Although there were no abnormalities in the renal function or urinalysis 2 months after transplantation, a routine kidney allograft biopsy revealed evidence of mesangial proliferation and cellular crescent formation. Mesangial deposition for IgA and C3 was noted, and he was diagnosed with recurrent HSPN histologically. Since the renal function and urinalysis findings deteriorated 5 months after transplantation, 2 courses of steroid pulse therapy were performed but were ineffective. EAT using 0.5% zinc chloride solution once per day was combined with the third course of steroid pulse therapy, as there were signs of chronic epipharyngitis. His renal function recovered 3 months after daily EAT and has been stable for 1.5 years since transplantation. Daily EAT continued for >3 months might be a suitable strategy for treating recurrent HSPN in cases of kidney transplantation.

[Multicenter Follow-up Survey on Radiation Dose Levels in Cardiovascular X-ray Apparatus under Percutaneous Coronary Intervention Conditions].

It is important to optimize the exposure dose when conducting interventional radiology, but optimization is difficult for medical centers to achieve independently. In 2005, we administered a questionnaire on the measurement of dose rates and awareness of exposure reduction when performing percutaneous coronary intervention. Ten years later, we conducted a follow-up survey of the same 31 centers to determine the current situation and identify trends. The results of the survey showed that the mean fluoroscopy dose rate decreased to 55% of the 2005 value, from 28.2 to 15.6 mGy/min, and the mean radiography dose rate decreased to 71% of the 2005 value, from 4.2 to 3.0 mGy/s. Dose rates for both fluoroscopy and radiography decreased by 84% of facilities. The results also indicated greater cooperation by physicians compared to 10 years ago. In particular, there was a considerable increase in the exchange of ideas with physicians regarding exposure, suggesting a stronger level of interest in exposure. The overall score for questionnaire items was 33% higher than that in the previous survey. These results show that in the past 10 years, awareness of exposure reduction has improved, and dose optimization has been a major factor in the downward trend in dose rates in radiography and fluoroscopy.

Correction to: A nationwide survey on clinical practice patterns and bleeding complications of percutaneous native kidney biopsy in Japan.

In the original publication, some errors have been found in the alignment of Table 9. The corrected table is given below.

Safety assessment of the candidate oral probiotic Lactobacillus crispatus YIT 12319: Analysis of antibiotic resistance and virulence-associated genes.

Lactobacillus crispatus YIT 12319 (LcY) was isolated from the oral cavity of a healthy subject as a new candidate probiotic with potential benefits for oral health. As a safety assessment of LcY, we performed an antibiotic susceptibility test and virulence-associated gene analysis using a draft genome sequence. Susceptibility to 15 antibiotics was analyzed according to the standard method of the International Dairy Federation/International Organization for Standardization, as recommended by the European Food Safety Authority. The results showed that the minimum inhibitory concentrations of LcY were not higher than those of other L. crispatus strains, which have not acquired resistance to any antibiotics, suggesting that LcY had no externally acquired transmissible antibiotic resistance genes. Analysis of virulence-associated genes using the draft genome of LcY found that there were fewer potential virulence-associated genes in LcY than in other probiotics. These findings suggest that LcY could be a candidate probiotic based on its safety profile.

A nationwide survey on clinical practice patterns and bleeding complications of percutaneous native kidney biopsy in Japan.

BACKGROUND: Practice patterns and bleeding complications of percutaneous native kidney biopsy (PNKB) have not recently been investigated and the Japanese Society of Nephrology performed a nationwide questionnaire survey in 2018. METHODS: The survey consisted of nine sections about PNKB: (1) general indications; (2) indications for high-risk patients; (3) informed consent; (4) pre-biopsy evaluation; (5) procedures; (6) sedation; (7) post-biopsy hemostasis, bed rest, and examinations; (8) bleeding complications; and (9) specimen processing. A supplementary survey examined bleeding requiring transcatheter arterial embolization (TAE). RESULTS: Overall, 220 directors of facilities (nephrology facility [NF], 168; pediatric nephrology facility [PF], 52) completed the survey. Indications, procedures, and monitoring protocols varied across facilities. Median lengths of hospital stay were 5 days in NFs and 6 days in PFs. Gauge 14, 16, 18 needles were used in 5%, 56%, 33% in NFs and 0%, 63%, 64% in PFs. Mean limits of needle passes were 5 in NFs and 4 in PFs. The bed rest period was 16-24 h in 60% of NFs and 65% of PFs. Based on 17,342 PNKBs, incidence rates of macroscopic hematuria, erythrocyte transfusion, and TAE were 3.1% (NF, 2.8%; PF, 6.2%), 0.7% (NF, 0.8%; PF, 0%), and 0.2% (NF, 0.2%; PF, 0.06%), respectively. Forty-six percent of facilities processed specimens all for light microscopy, immunofluorescence, and electron microscopy, and 21% processed for light microscopy only. Timing of bleeding requiring TAE varied among PNKB cases. CONCLUSION: Wide variations in practice patterns of PNKB existed among facilities, while PNKBs were performed as safely as previously reported.

Effects of Protein-Energy Wasting (PEW) and hyperphosphatemia on the prognosis in Japanese maintenance hemodialysis patients: A five-year follow-up observational study.

BACKGROUND & AIMS: In dialysis patients, malnutrition is a poor prognostic factor. In patients with chronic kidney disease (CKD), malnutrition is qualitatively different from general malnutrition, which is defined as "Protein-Energy Wasting (PEW)." Dietary therapy for the enhancement of PEW requires the aggressive intake of protein. Conversely, as protein intake and phosphorus intake correlate positively, increasing the protein intake increases the phosphorus intake, which is a poor prognostic factor in dialysis patients. One of the treatments for hyperphosphatemia in dialysis patients is the intake restriction of phosphorus by dietary counseling. However, protein uptake to maintain and augment the nutritional status and the protein intake restriction to correct hyperphosphatemia are contradictory treatments. Hence, this study aims to investigate the effects of PEW and hyperphosphatemia on the prognosis in hemodialysis patients. METHODS: We enrolled 60 outpatients who underwent maintenance hemodialysis for 6 months (May-November 2012) at Iga City General Hospital (Mie, Japan). In November 2012, we assessed the presence or absence of PEW and hyperphosphatemia in patients and evaluated the survival rate over the next 5 years. RESULTS: Overall, 10 patients (17%) were diagnosed as PEW. While 17 patients (28%) exhibited average phosphorus level >6.0 mg/dL (hyperphosphatemia). The 5-year survival rate was 30% in the PEW group, 66% in the non-PEW group, 57% in the hyperphosphatemia group, and 61% in the non-hyperphosphatemia group. A statistically significant difference existed between the PEW and non-PEW groups (P = 0.021). However, we observed no significant difference between the hyperphosphatemia and non-hyperphosphatemia groups. CONCLUSIONS: This study suggests that PEW affects the prognosis more than hyperphosphatemia in maintenance hemodialysis patients. The normalization of the serum phosphorus level by the protein intake restriction could prevent secondary hyperparathyroidism and vascular calcification. Conversely, restricting the protein intake poses a risk of malnutrition. In fact, early death occurred in patients with PEW in this study. Perhaps, patients with PEW should prioritize improving their nutritional status rather than controlling the serum phosphorus level.