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.

Artificial Intelligence Reporting Guidelines' Adherence in Nephrology for Improved Research and Clinical Outcomes.

The use of artificial intelligence (AI) in healthcare is transforming a number of medical fields, including nephrology. The integration of various AI techniques in nephrology facilitates the prediction of the early detection, diagnosis, prognosis, and treatment of kidney disease. Nevertheless, recent reports have demonstrated that the majority of published clinical AI studies lack uniform AI reporting standards, which poses significant challenges in interpreting, replicating, and translating the studies into routine clinical use. In response to these issues, worldwide initiatives have created guidelines for publishing AI-related studies that outline the minimal necessary information that researchers should include. By following standardized reporting frameworks, researchers and clinicians can ensure the reproducibility, reliability, and ethical use of AI models. This will ultimately lead to improved research outcomes, enhanced clinical decision-making, and better patient management. This review article highlights the importance of adhering to AI reporting guidelines in medical research, with a focus on nephrology and urology, and clinical practice for advancing the field and optimizing patient care.

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.

Dialysis-related Amyloidosis Presenting as a Fever of Unknown Origin: Symptoms and Management.

A 74-year-old woman with a 34-year history of hemodialysis presented with an intermittent fever, which later coincided with recurrent bilateral shoulder and hip joint pain. Imaging studies suggested amyloid arthropathy, which was histologically confirmed by a synovial biopsy. Increasing ß2-microglobulin clearance during dialysis alone attenuated the intermittent fever and joint pain, but the symptoms did not disappear until the administration of prednisolone 10 mg/day. Reported cases of dialysis-related amyloidosis with a fever imply that changing to blood purification methods with high ß2-microglobulin clearance is crucial for controlling the condition long-term, whereas concurrent use of anti-inflammatory agents promptly alleviates the symptoms.

Relationship between Lower Extremity Peripheral Arterial Disease and Mild Cognitive Impairment in Hemodialysis Patients.

BACKGROUND: The link between arterial stiffness and mild cognitive impairment (MCI) in patients on hemodialysis (HD) has been receiving increased attention. The purpose of this study was to investigate the relationship between cognitive function and ankle brachial index (ABI) and toe brachial index (TBI) values in patients on hemodialysis. Of the 100 participants (mean age: 67.9 years; average history of hemodialysis: 7.3 years). Of these, 46.0% had MCI. The MoCA-J scores were significantly higher in the ABI ≥ 1.06 group. However, the MoCA-J scores divided into the two groups according to the TBI cutoff value were not significantly different. In a multiple regression model with the MoCA-J scores as the objective variable, the ABI was a significantly associated factor. This study indicates that a low ABI might be associated with MCI.

Malnutrition and Insulin Resistance May Interact with Metabolic Syndrome in Prevalent Hemodialysis Patients.

BACKGROUND: We sought to determine the prevalence of metabolic syndrome (Mets) and whether 100 cm2 of visceral fatty area (VFA) measured by computed tomography (CT) validates the criteria of waist circumference (WC) in hemodialysis (HD) patients. METHODS: The study comprised 141 HD patients. Mets was defined according to the criteria of Adult Treatment Panel III (ATP III) and the modified criteria of National Cholesterol Education Program (NCEP) that defines abdominal obesity as a WC of >=85 cm in men and >=90 cm in women. RESULTS: The prevalence of Mets was 31.9% in men and 13.6% in women. However, the prevalence of patients with a body mass index over 25 in all HD patients was only 11.2%. The visceral fatty area (VFA) measured by CT showed a strong positive correlation with WC. The patients with Mets, comparing with those without Mets, have significantly shorter duration of HD, higher high-sensitive C-reactive protein, and higher Homeostatic Model Assessment for Insulin Resistance (HOMA-IR). In the patients with Mets, there was a significant negative correlation between HOMA-IR and serum albumin levels. Multivariate logistic regression analysis showed that HOMA-IR and short duration of HD were chosen as independent risk factors for Mets. CONCLUSIONS: Mets is more prevalent in HD patients. In Japanese HD patients, 100 cm2 of VFA corresponded to a WC of 85 cm in men and 90 cm in women, thus confirming the validity of the modified criteria. HOMA-IR and serum albumin were significantly correlated in HD patients with Mets.

Transcranial Doppler Echography Measurement in Hemodialysis Patients: The Potential Role of Angiotensin II Receptor Blockades on Cerebrovascular Circulation.

BACKGROUND: Although hemodialysis (HD) patients have an elevated risk of strokes, there are few reports about transcranial doppler (TCD) echography measurements. It is well-known that angiotensin II receptor blockades (ARBs) protect against cardiovascular complications. In this study, we measured intracranial artery (ICA) velocity using TCD echography and studied the associated factors with its velocity in HD patients by a comparison with or without ARBs. METHODS: We conducted a cross-sectional study in a single hospital. We included 61 patients who had measurable ICA velocity by TCD echography. Among them, the ARB usage group consisted of 22 subjects, whilst the non-ARB usage group consisted of 39 subjects. RESULTS: Patients in the ARB (+) and ARB (-) groups did not show any difference in basic characteristics. ICA blood flow velocity in all intracranial arteries tended to show greater values in the ARB group than those in the non-ARB group. Particularly, blood velocity in the middle cerebral artery (MCA) (maximal flow velocity) statistically increased in the ARB group, respectively. In a univariate analysis, MCA maximum velocity was significantly associated with ARB usage (p = 0.011) and low hematocrit levels (p = 0.045). The multivariate analysis chose only ARB usage as an independent factor associated with left MCA maximum velocity (p = 0.022). CONCLUSIONS: We showed that dialysis patients with ARBs have significantly higher ICA blood velocity. ARBs might have a potential benefit for maintaining ICA blood flow in HD patients.

Impact of the 3% Oxygen Desaturation Index via Overnight Pulse Oximetry on Cardiovascular Events and Death in Patients Undergoing Hemodialysis: A Retrospective Cohort Study.

It is unclear whether the severity of sleep-disordered breathing (SDB) affects the risk of cardiovascular events and mortality in patients undergoing hemodialysis (HD). We determined the severity of SDB with the 3% oxygen desaturation index (ODI) via overnight pulse oximetry. This study was a retrospective cohort, observational study of 134 patients on maintenance HD at a single center. They were divided into four groups according to SDB severity (normal, mild, moderate, and severe), and were followed. The baseline characteristics of all patients were as follows: the median age was 67 (interquartile range, 59-75) years, 64.2% were men, 37.3% were diabetic, and the median duration of HD was 69 (29-132) months. During follow-up, major adverse cardiovascular events (MACEs) occurred in 71 patients and deaths in 60 (including 32 cardiovascular deaths). Severe SDB was an independent risk factor for MACEs (hazard ratio [HR] = 4.66, 95% confidence interval [CI] = 1.87-11.61, p = 0.001) and all-cause death (HR = 5.74, 95% CI = 1.92-16.70, p = 0.001). Severe SDB had a statistically significant impact on the risk of MACEs and mortality in patients undergoing HD. The severity of the 3% ODI via overnight pulse oximetry may be a useful marker as a risk factor for cardiovascular outcomes and mortality in these patients.

Impact of Arterial Calcification of the Lower Limbs on Long-Term Clinical Outcomes in Patients on Hemodialysis.

Lower limbs' arterial calcification is significantly associated with the clinical severity of lower extremity artery disease (LEAD) in patients undergoing hemodialysis (HD). However, the association between arterial calcification of the lower limbs and long-term clinical outcomes in patients on HD has not been elucidated. Calcification scores of the superficial femoral artery (SFACS) and below-knee arteries (BKACS) were quantitatively evaluated in 97 HD patients who were followed for 10 years. Clinical outcomes, including all-cause and cardiovascular mortality, cardiovascular events, and limb amputation were evaluated. Risk factors for clinical outcomes were evaluated using univariate and multivariate Cox proportional hazard analyses. Furthermore, SFACS and BKACS were divided into three groups (low, middle, and high), and their associations with clinical outcomes were evaluated using Kaplan-Meier analysis. SFACS, BKACS, C-reactive protein, serum albumin, age, diabetes, presence of ischemic heart disease, and critical limb-threatening ischemia were significantly associated with 3-year and 10-year clinical outcomes in the univariate analysis. Multivariate analysis showed that SFACS was an independent factor associated with 10-year cardiovascular events and limb amputations. Kaplan-Meier life table analysis showed that higher SFACS and BKACS levels were significantly associated with cardiovascular events and mortality. In conclusion, long-term clinical outcomes and the risk factors in patients undergoing HD were evaluated. Arterial calcification of the lower limbs was strongly associated with 10-year cardiovascular events and mortality in patients undergoing HD.

Association between zinc deficiency and aorta stiffness in non-diabetic hemodialysis patients.

OBJECTIVES: Zinc deficiency (Zn < 60 µg/dL) is known to play an important role for vascular calcification. However, little data is available regarding the association between zinc deficiency and aorta stiffness in dialysis patients. Thus, we studied the relationship between zinc deficiency and aorta stiffness in non-diabetic hemodialysis (HD) patients. METHODS: Of 150 patients receiving maintenance HD at our hospital, we included 79 non-diabetic HD patients (age: 70±11 years, 49 men) after excluding 71 diabetic HD patients. Zinc deficiency was defined as Zn <60 µg/dL during pre-HD blood sampling. The association between zinc deficiency and aorta stiffness was analyzed. Aorta stiffness was evaluated as brachial-ankle pulse wave velocity (baPWV). Other surrogate markers for cardiovascular complications were also measured. RESULTS: The zinc deficiency group (ZD group) included 45 patients (57.0%). Compared to the zinc non-deficiency group (ZND group), patients with ZD group were significantly older, higher levels of CRP and hypoalbuminemia. Moreover, they had significantly higher levels of baPWV, and lower levels of ankle-brachial pressure index (ABI) (p<0.05). After adjusting for hypoalbuminemia, and CRP, multivariate analysis showed that age and zinc level were independent predictors of baPWV. CONCLUSION: The study suggested that zinc deficiency may be an independent risk factor for aorta stiffness, even after adjusting for malnutrition and inflammation.

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.

Impact of Contrast-Induced Nephropathy on Long-Term Renal Function after Coronary Angiography and Contrast-Enhanced Computed Tomography.

Background: It remains unclear whether contrast-induced nephropathy (CIN) has a prognostic impact on subsequent renal dysfunction and whether deteriorating renal function is a risk factor for CIN. This study aimed to evaluate the occurrence of CIN in patients with pre-existing renal dysfunction and investigate the long-term effects of worsening renal function after coronary angiography or contrast-enhanced computed tomography (CT). The prognostic factors of worsening renal dysfunction were also analyzed. Methods: This was a prospective cohort study of patients at risk for CIN, defined as an estimated glomerular filtration rate (eGFR) <60 mL/min/1.73 m2 on coronary angiography or eGFR <45 mL/min/1.73 m2 on contrast-enhanced CT. Serum creatinine levels and the 2-year prognosis were evaluated. CIN was defined as an increase in serum creatinine level by more than 0.5 mg/dL or a 25% increase from the previous value within 72 hours after contrast administration. The primary endpoint was the proportion of patients who had serum Cr doubling or induction of dialysis within 2 years according to CIN occurrence. Results: Of the 410 patients, 19 patients developed CIN (8/142 patients on coronary angiography and 11/268 patients on contrast-enhanced CT), and 38 patients had worsened renal function (21/142 patients on coronary angiography and 17/268 patients on contrast-enhanced CT). CIN was not associated with worsening renal function at 2 years. Analysis by renal function at the time of coronary angiography or contrast-enhanced CT (i.e., eGFR ≥30 ml/min/1.73 m2 and eGFR ≤1.73 m2) found no between-group difference in the occurrence of CIN. Conclusions: CIN is not a prognostic risk factor for the long-term of chronic kidney disease after coronary angiography or contrast-enhanced CT. Pre-existing renal dysfunction is also not a risk factor for CIN, even if the eGFR is <30 ml/min/1.73 m2.

Association between Anti-Erythropoietin Receptor Antibodies and Cardiac Function in Patients on Hemodialysis: A Multicenter Cross-Sectional Study.

Cardiac dysfunction is an important prognostic predictor of cardiovascular mortality in patients on hemodialysis (HD). Erythropoietin (EPO) has been reported to improve cardiac function by binding to the EPO receptor (EPOR) on cardiomyocytes. This study investigated whether anti-EPOR antibodies were associated with left ventricular cardiac function in patients undergoing HD. This multicenter, cross-sectional observational study included 377 patients (median age, 70 years; 267 (70.8%) males) with chronic kidney disease (CKD) undergoing stable maintenance HD. Serum levels of anti-EPOR antibodies were measured, and echocardiography was used to assess the left ventricular mass index (LVMI) and left ventricular ejection fraction (LVEF). Anti-EPOR antibodies were found in 17 patients (4.5%). LVMI was greater (median of 135 g/m2 vs. 115 g/m2, p = 0.042), and the prevalence of LVEF < 50% was higher (35.3% vs. 15.6%, p = 0.032) in patients with anti-EPOR antibodies than in those without. Multivariable linear regression and logistic regression analysis (after adjusting for known risk factors of heart failure) revealed that anti-EPOR antibodies were independently associated with LVMI (coefficient 16.2%; 95% confidence interval (CI) 1.0−35.0%, p = 0.043) and LVEF <50% (odds ratio 3.20; 95% CI 1.05−9.73, p = 0.041). Thus, anti-EPOR antibody positivity was associated with left ventricular dysfunction in patients undergoing HD.

Acquired aplastic anemia complicated with anti-glomerular basement membrane disease successfully treated with immunosuppressive therapy: a case report.

BACKGROUND: Aplastic anemia (AA) is a rare but fatal disorder characterized by pancytopenia due to bone marrow hypoplasia. Anti-glomerular basement membrane disease (anti-GBM disease) is an immune complex small-vessel vasculitis that presents as rapidly progressive glomerulonephritis and/or pulmonary hemorrhage. Although both involve autoreactive T cells that are partially triggered by human leukocyte antigen (HLA)-DR15, there have been no reports of their co-existence and the treatment strategy is not well understood. CASE PRESENTATION: A 67-year-old woman presented with fever, malaise, and acute kidney injury with proteinuria and hematuria requiring hemodialysis. She was diagnosed with anti-GBM antibody disease based on high serum anti-GBM antibody titer and crescentic glomerulonephritis on a renal biopsy. Pulse administration of methylprednisolone (MP), oral prednisolone (PSL), and plasmapheresis were performed. Only 2 weeks after the diagnosis of anti-GBM disease, the patient developed pancytopenia requiring frequent blood transfusions. The blood cell count did not recover even 1 month after discontinuing the drugs that could cause pancytopenia. Bone marrow examination showed hypocellularity without abnormal infiltrates or fibrosis, which led to the diagnosis of severe acquired AA. Further HLA phenotyping revealed that she had HLA-DR15. Increased dose of PSL with the secondary MP pulse and the addition of cyclosporine improved pancytopenia. Although she remained dialysis-dependent, anti-GBM disease and pancytopenia did not recur for more than 2 years. CONCLUSIONS: We report the first case of acquired AA complicated with anti-GBM disease in an elderly woman with HLA-DR15, which was successfully treated with immunosuppressive therapy (IST). This report is valuable not only because it shows they may co-occur, but also because it provides a therapeutic option for this complex condition. It was also suggested that pancytopenia in patients with anti-GBM disease recalls serious hematologic diseases including AA that require immediate treatment based on bone marrow examination.

Prevalence of mild cognitive impairment and its association with handgrip strength in patients on hemodialysis.

Dementia is associated with a high risk of death and hospitalization among patients on hemodialysis (HD). We retrospectively evaluated the prevalence of mild cognitive impairment (MCI) in 421 patients on maintenance HD across nine facilities and investigated whether decreased handgrip strength was associated with decreased cognitive function. The Montreal Cognitive Assessment-Japan (MoCA-J) score and handgrip strength were measured. The mean age was 69.8 ± 11.2 years, and the median dialysis vintage 74.5 (IQR 30-150) months. The median MoCA-J score was 25 (IQR 21-27), and MCI was confirmed in 245 (58.2%) patients. Both the MoCA-J score and MoCA-J executive score were associated with age, history of cerebrovascular disease (CVA), and handgrip strength after adjustments. We found, among patients on HD aged under 70 years with a history of CVA, a handgrip strength < 90% (25.2 kg in males and 16.2 kg in females) correlated with significantly lower MoCA-J scores. A high prevalence of MCI and decreased handgrip strength were observed in patients on HD. Handgrip strength may be useful for the easy detection of MCI. A decrease in handgrip strength would allow for the early detection of MCI, especially among patients on HD aged under 70 years with a history of CVA.

MPO-ANCA-associated vasculitis after the Pfizer/BioNTech SARS-CoV-2 vaccination.

Vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has demonstrated high efficacy at preventing coronavirus disease 2019 (COVID-19) and a favorable safety profile, however it has also been reported that COVID-19 vaccines may put increase of immune-mediated disease. We herein report a case of MPO-anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis following the mRNA vaccine BNT162b2 (Pfizer/BioNTech) for COVID-19. Although the causal relationship between vaccine and ANCA-associated vasculitis is uncertain, environmental and genetic factors may have set the stage for the development of vasculitis, and the vaccine may have triggered a domino effect.

The Japanese Society for Apheresis clinical practice guideline for therapeutic apheresis.

Most of the diseases for which apheresis therapy is indicated are intractable and rare, and each patient has a different background and treatment course prior to apheresis therapy initiation. Therefore, it is difficult to conduct large-scale randomized controlled trials to secure high-quality evidence. Under such circumstances, the American Society for Apheresis (ASFA) issued its guidelines in 2007, which were repeatedly revised until the latest edition in 2019. The ASFA guidelines are comprehensive. However, in the United States, a centrifugal separation method is mainly used for apheresis, whereas the mainstream procedure in Japan is the membrane separation method. The target diseases and their backgrounds are different from those in Japan. Due to these differences, the direct adoption of the ASFA guidelines in Japanese practice creates various problems. One of the features of apheresis in Japan is the development of treatment methods using hollow-fiber devices such as double filtration plasmapheresis (DFPP) and selective plasma exchange and adsorption-type devices such as polymyxin B-immobilized endotoxin adsorption columns. Specialists in emergency medicine, hematology, collagen diseases/rheumatology, respiratory medicine, cardiovascular medicine, gastroenterology, neurology, nephrology, and dermatology who are familiar with apheresis therapy gathered for this guideline, which covers 86 diseases. In addition, since apheresis therapy involves not only physicians but also clinical engineers, nurses, dieticians, and many other medical professionals, this guideline was prepared in the form of a worksheet so that it can be easily understood at the bedside. Moreover, to the clinical purposes, this guideline is designed to summarize apheresis therapy in Japan and to disseminate and further develop Japanese apheresis technology to the world. As diagnostic and therapeutic techniques are constantly advancing, the guidelines need to be revised every few years. In order to ensure the high quality of apheresis therapy in Japan, both the Japanese Society for Apheresis Registry and the guidelines will be inseparable.

Recurrent hemorrhagic shock from hemorrhagic cystitis due to neurogenic bladder.

INTRODUCTION: Hemorrhagic cystitis is characterized by gross hematuria, with hemorrhagic shock a rare complication. However, to our knowledge, its exact frequency has not been reported. CASE PRESENTATION: We report a case of an 86-year-old woman who showed repeated hemorrhagic cystitis with massive bleeding and hemorrhagic shock. The hemorrhagic cystitis was supposedly caused by the administration of aspirin and a neurogenic bladder. A urethral catheter was indwelled and hemorrhagic cystitis subsequently ceased. CONCLUSION: A review of patients with hemorrhagic cystitis at our hospital showed that only 3.3% experienced hemorrhagic shock. This case was even rarer because the patient experienced recurrent hemorrhagic shocks. A neurogenic bladder, which reduces the bladder's ability to function as a uroepithelial barrier against recurrent bacterial infections, caused the condition in this case. This report highlights how hemorrhagic cystitis can sometimes cause hemorrhagic shock.