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Aims/Introduction: This multicenter cohort study retrospectively assessed the association between polar vasculosis and the progression of diabetic kidney disease (DKD) in type 2 diabetes. Materials and Methods: We enrolled 811 patients with type 2 diabetes, biopsy‐proven DKD, and proteinuria (≥0.15 g/g creatinine [g/day]). The association between polar vasculosis and other kidney lesions was explored. The outcome was DKD progression defined as a composite of renal replacement therapy initiation or 50% decline in estimated glomerular filtration rate (eGFR) from baseline. Results: Of the 811 cases, 677 (83.5%) had polar vasculosis. In multivariate logistic regression analysis, subendothelial widening of the glomerular basement membrane, glomerulomegaly, glomerular class in the Renal Pathology Society classification ≥IIb, vascular lesions, age, eGFR, and hemoglobin A1c were positively associated with polar vasculosis, whereas interstitial fibrosis and tubular atrophy (IFTA) was negatively associated with polar vasculosis. During a median follow‐up of 5.2 years, progression of DKD occurred in 322 of 677 (7.4 events/100 person‐years) and 79 of 134 (11.4 events/100 person‐years) cases with and without polar vasculosis, respectively. Kaplan–Meier analysis showed that polar vasculosis was associated with lower cumulative incidences of DKD progression. Multivariate Cox regression analyses showed that polar vasculosis was associated with a lower risk of DKD progression, regardless of eGFR or proteinuria subgroups. These associations between polar vasculosis and better kidney outcome were unchanged considering all‐cause mortality before DKD progression as a competing event. Conclusions: This study showed that polar vasculosis of DKD was associated with less advanced IFTA and a better kidney outcome in type 2 diabetes with proteinuria. [ABSTRACT FROM AUTHOR]

Background Prognosticating disease progression in patients with diabetic kidney disease (DKD) is challenging, especially in the early stages of kidney disease. Anemia can occur in the early stages of kidney disease in diabetes. We therefore postulated that serum hemoglobin (Hb) concentration, as a reflection of incipient renal tubulointerstitial impairment, can be used as a marker to predict DKD progression. Methods Drawing on nationally representative data of patients with biopsy-proven DKD, 246 patients who had an estimated glomerular filtration rate (eGFR)  ≥60 mL/min/1.73 m2 at renal biopsy were identified: age 56 (45–63) years; 62.6% men; Hb 13.3 (12.0–14.5) g/dL; eGFR 76.2 (66.6–88.6) mL/min/1.73 m2; urine albumin-to-creatinine ratio 534 (100–1480) mg/g Crea. Serum Hb concentration was divided into quartiles: ≤12, 12.1–13.3, 13.4–14.5 and ≥14.6 g/dL. The association between serum Hb concentration and the severity of renal pathological lesions was explored. A multivariable Cox regression model was used to estimate the risk of DKD progression (new onset of end-stage kidney disease, 50% reduction of eGFR or doubling of serum creatinine). The incremental prognostic value of DKD progression by adding serum Hb concentration to the known risk factors of DKD was assessed. Results Serum Hb levels negatively correlated with all renal pathological features, especially with the severity of interstitial fibrosis (ρ  =   −0.52; P   <   0.001). During a median follow-up of 4.1 years, 95 developed DKD progression. Adjusting for known risk factors of DKD progression, the hazard ratio in the first, second and third quartile (the fourth quartile was reference) were 2.74 [95% confidence interval (CI) 1.26–5.97], 2.33 (95% CI 1.07–5.75) and 1.46 (95% CI 0.71–3.64), respectively. Addition of the serum Hb concentration to the known risk factors of DKD progression improved the prognostic value of DKD progression (the global Chi-statistics increased from 55.1 to 60.8; P   <   0.001). Conclusions Serum Hb concentration, which reflects incipient renal fibrosis, can be useful for predicting DKD progression in the early stages of kidney disease. [ABSTRACT FROM AUTHOR]

PAX2 is a transcription factor essential for kidney development and the main causative gene for renal coloboma syndrome (RCS). The mechanisms of PAX2 action during kidney development have been evaluated in mice but not in humans. This is a critical gap in knowledge since important differences have been reported in kidney development in the two species. In the present study, we hypothesized that key human PAX2-dependent kidney development genes are differentially expressed in nephron progenitor cells from induced pluripotent stem cells (iPSCs) in patients with RCS relative to healthy individuals. Cap analysis of gene expression revealed 189 candidate promoters and 71 candidate enhancers that were differentially activated by PAX2 in this system in three patients with RCS with PAX2 mutations. By comparing this list with the list of candidate Pax2-regulated mouse kidney development genes obtained from the Functional Annotation of the Mouse/Mammalian (FANTOM) database, we prioritized 17 genes. Furthermore, we ranked three genes—PBX1, POSTN, and ITGA9—as the top candidates based on closely aligned expression kinetics with PAX2 in the iPSC culture system and susceptibility to suppression by a Pax2 inhibitor in cultured mouse embryonic kidney explants. Identification of these genes may provide important information to clarify the pathogenesis of RCS, human kidney development, and kidney regeneration. [ABSTRACT FROM AUTHOR]

Carnitine/organic cation transporter 1 (OCTN1) is the only known uptake transporter for ergothioneine which is a food-derived strong antioxidant amino acid that is absorbed by OCTN1. We previously reported the roles of OCTN1/ergothioneine in the progression of kidney fibrosis in ischemic kidney disease. In this study, we evaluated the roles of OCTN1 in the progression of diabetic kidney disease. A diabetic kidney disease model was induced in octn1 knockout and wild-type mice by streptozotocin (STZ). Oxidative stress, represented by urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG), were higher in the octn1 knockout mice. Azan- and Sirius red-positive areas increased significantly in the octn1 knockout mice. Gene expression was evaluated by cluster analysis, and shown to be different in the octn1 knockout mice compared with the wild-type mice. In a pathway analysis, the pathway associated with the cytoskeleton and cell adhesion increased. In accordance with interstitial fibrosis in octn1 knockout mice, gene expression of moesin in the injured kidney, known as an associated protein of cytoskeleton and cell membranes, was doubled 28 weeks after STZ injection. In addition, the moesin protein was expressed in a part of α-SMA-positive renal tubular epithelial cells. These findings were confirmed by cultured murine proximal tubular epithelial cells: The expression of moesin was induced under oxidative stress with hydrogen peroxide. These data indicate that OCTN1 would play some roles in progression of interstitial fibrosis under oxidative stress via moesin expression in diabetic kidney disease. [ABSTRACT FROM AUTHOR]

Proteinuria has been considered to be the hallmark of diabetic kidney disease and to precede renal function loss. However, it has become clear that a substantial proportion of patients either with type 1 diabetes or type 2 diabetes have renal function loss without proteinuria, known as nonproteinuric diabetic kidney disease. Despite increasing recognition of the prevalence of nonproteinuric diabetic kidney disease, data on this phenotype of diabetic kidney disease is sparse. This review describes ever known clinical and pathological manifestations, renal prognosis, and mortality in patient with nonproteinuric diabetic kidney disease. [ABSTRACT FROM AUTHOR]

Aims/Introduction: The present retrospective study investigated the impact of renal arteriosclerosis (AS) and hypertension (HT) on long‐term renal and cardiovascular outcomes in Japanese type 2 diabetes patients with biopsy‐proven diabetic nephropathy. Materials and Methods: A total of 185 patients were enrolled. Patients were divided into four groups stratified by renal AS status and the presence of HT. The outcomes for this study were the first occurrence of renal events (a need for dialysis or a 30% decline in estimated glomerular filtration rate from baseline) and cardiovascular events (cardiovascular death, non‐fatal myocardial infarction, coronary intervention or non‐fatal stroke). Results: The proportion of renal AS scores ≥1 was 88.3% among patients with normal‐range blood pressure (BP) and 95.4% among patients with HT. During a mean follow‐up period of 7.6 years, 129 episodes of renal composite events and 55 episodes of cardiovascular events were observed. Compared with patients with no renal AS and normal‐range BP, a renal AS score ≥1 increased the risk of renal composite events with a multivariable‐adjusted hazard ratio of 3.21 (95% confidence interval [95% CI] 1.27–8.14) in patients with normal‐range BP and 4.99 (95% CI 1.98–12.54) in patients with HT, whereas renal AS score ≥1 increased the risk of cardiovascular events with a multivariable‐adjusted hazard ratio of 6.06 (95% CI 1.24–29.61) in patients with normal‐range BP and 10.02 (95% CI 1.92–52.39) in patients with HT. Conclusions: Renal AS was associated with increasing risks for renal composite events and cardiovascular events in both normal‐range BP and HT. The risks of renal composite events and cardiovascular events were the highest in both renal AS and HT. [ABSTRACT FROM AUTHOR]

Diabetic kidney disease is the major cause of end-stage kidney disease in developed countries. However, the onset of kidney disorder and the progression pattern of kidney dysfunction and proteinuria greatly vary cases by cases. Therefore, risk classification with clinical data and pathological findings is important. Recent clinico-pathological study with kidney biopsy samples from diabetic patients revealed that pathological changes of diabetic nephropathy are characteristic and have special impacts on prognosis in each clinical stage. Moreover, comparison of the clinico-pathological findings of diabetic nephropathy with hypertensive nephrosclerosis revealed that there are few differences in their pathological findings in cases with low albuminuria and preserved estimated glomerular filtration rate (eGFR). Because it is so difficult to clearly distinguish pure kidney lesions caused by diabetes and kidney lesions due to effects other than diabetes, it is vital that these overlapped pathological findings be confirmed on kidney biopsy in cases of early stage diabetes. Further research is warranted regarding the pathogenesis of diabetic nephropathy and indication of kidney biopsy in diabetic cases. [ABSTRACT FROM AUTHOR]

Background: Nephrosclerosis is an increasingly reason for dialysis in Japan. However, kidney biopsy specimens for hypertensive nephrosclerosis are very limited; thus, the pathologic evaluation of hypertensive nephrosclerosis currently remains unclear.Methods: Clinical and pathologic data of a total of 184 biopsy-confirmed hypertensive nephrosclerosis patients were collected from 13 centers throughout Japan. Seven pathological findings were assessed in this study. The outcomes of interest for this study were dialysis, composite kidney events, cardiovascular events, and all-cause mortality.Results: The Green and Yellow (G&Y), Orange, and Red groups of the chronic kidney diseases (CKD) heat map contained 36, 57, and 91 cases, respectively. The mean observation period was 7.3 ± 5.2 (median, IQR; 6.1, 2.6-9.7) years. Global glomerulosclerosis (GScle), interstitial fibrosis and tubular atrophy (IFTA), arteriolar hyalinosis in Red exhibited higher scores than those in G&Y and Orange. The incidence rates of the composite kidney end points in 100 person-years for the G&Y, Orange, and Red groups were 1.42, 2.16, and 3.98, respectively. In the univariate Cox analysis for the composite kidney end points, GScle, IFTA and interstitial cell infiltration exhibited statistically significant high hazard ratios (1.18, 1.84, 1.69, respectively). However, after adjustment for clinical and medication data, the Red group in the CKD heat map category was risk factor for the composite kidney end points (HR 9.51).Conclusions: In summary, although pathologic findings had minor impacts on the prediction of composite outcomes in this study, the clinical stage of the CKD heat map is a good predictor of composite kidney events. [ABSTRACT FROM AUTHOR]

Background: The Japanese classification of diabetic nephropathy reflects the risks of mortality, cardiovascular events and kidney prognosis and is clinically useful. Furthermore, pathological findings of diabetic nephropathy are useful for predicting prognoses. In this study, we evaluated the characteristics of pathological findings in relation to the Japanese classification of diabetic nephropathy and their ability to predict prognosis.Methods: The clinical data of 600 biopsy-confirmed diabetic nephropathy patients were collected retrospectively from 13 centers across Japan. Composite kidney events, kidney death, cardiovascular events, all-cause mortality, and decreasing rate of estimated GFR (eGFR) were evaluated based on the Japanese classification of diabetic nephropathy.Results: The median observation period was 70.4 (IQR 20.9-101.0) months. Each stage had specific characteristic pathological findings. Diffuse lesions, interstitial fibrosis and/or tubular atrophy (IFTA), interstitial cell infiltration, arteriolar hyalinosis, and intimal thickening were detected in more than half the cases, even in Stage 1. An analysis of the impacts on outcomes in all data showed that hazard ratios of diffuse lesions, widening of the subendothelial space, exudative lesions, mesangiolysis, IFTA, and interstitial cell infiltration were 2.7, 2.8, 2.7, 2.6, 3.5, and 3.7, respectively. Median declining speed of eGFR in all cases was 5.61 mL/min/1.73 m2/year, and the median rate of declining kidney function within 2 years after kidney biopsy was 24.0%.Conclusions: This study indicated that pathological findings could categorize the high-risk group as well as the Japanese classification of diabetic nephropathy. Further study using biopsy specimens is required to clarify the pathogenesis of diabetic kidney disease. [ABSTRACT FROM AUTHOR]

Background: There is increased interest in surrogate endpoints for clinical trials of chronic kidney disease.Methods: In this nationwide observational study of 456 patients with type 2 diabetes and clinically suspected diabetic nephropathy followed for a median of 4.2 years, we evaluated the association between estimated glomerular filtration rate (eGFR) and albuminuria at baseline or during follow-up and risk of ESRD.Results: Low eGFR (<60 mL/min/1.73 m2) and macroalbuminuria at enrollment were independently associated with risk of ESRD. In patients with macroalbuminuria, both ≤−50% change and −50 to −30% change in eGFR over 1 and 2 years were predictive of ESRD. The higher cut point (≥50% decline in eGFR) was more strongly predictive but less common. Remission of macroalbuminuria to normo-/microalbuminuria at 1 and 2 years was associated with a lower incidence of ESRD than no remission; however, it was not a determinant for ESRD independently of initial eGFR and initial protein-to-creatinine ratio.Conclusion: These results suggest that a ≥30% decline in eGFR over 1 or 2 years adds prognostic information about risk for ESRD in patients with type 2 diabetes and macroalbuminuria, supporting the consideration of percentage decline in eGFR as a surrogate endpoint among macroalbuminuric cases in type 2 diabetes. On the other hand, our study suggests that additional analyses on the relationship between remission of macroalbuminuria and risk of ESRD are needed in type 2 diabetes. [ABSTRACT FROM AUTHOR]

Background and objectives: The impact of the newly proposed pathological classification by the Japan Renal Pathology Society (JRPS) on renal outcome is unclear. So we evaluated that impact and created a new pathological scoring to predict outcome using this classification. Design, setting, participants, & measurements: A multicenter cohort of 493 biopsy-proven Japanese patients with diabetic nephropathy (DN) were analyzed. The association between each pathological factor—Tervaert’ and JRPS classifications—and renal outcome (dialysis initiation or 50% eGFR decline) was estimated by adjusted Cox regression. The overall pathological risk score (J-score) was calculated, whereupon its predictive ability for 10-year risk of renal outcome was evaluated. Results: The J-scores of diffuse lesion classes 2 or 3, GBM doubling class 3, presence of mesangiolysis, polar vasculosis, and arteriolar hyalinosis were, respectively, 1, 2, 4, 1, and 2. The scores of IFTA classes 1, 2, and 3 were, respectively, 3, 4, and 4, and those of interstitial inflammation classes 1, 2, and 3 were 5, 5, and 4 (J-score range, 0–19). Renal survival curves, when dividing into four J-score grades (0–5, 6–10, 11–15, and 16–19), were significantly different from each other (p<0.01, log-rank test). After adjusting clinical factors, the J-score was a significant predictor of renal outcome. Ability to predict 10-year renal outcome was improved when the J-score was added to the basic model: c-statistics from 0.661 to 0.685; category-free net reclassification improvement, 0.154 (-0.040, 0.349, p = 0.12); and integrated discrimination improvement, 0.015 (0.003, 0.028, p = 0.02). Conclusions: Mesangiolysis, polar vasculosis, and doubling of GBM—features of the JRPS system—were significantly associated with renal outcome. Prediction of DN patients’ renal outcome was better with the J-score than without it. [ABSTRACT FROM AUTHOR]

Background: The prevention of relapse and infection complications during remission maintenance therapy is required to improve the prognosis of patients with microscopic polyangiitis (MPA) showing rapidly progressive glomerulonephritis (RPGN). The clinicopathological characteristics of patients with ANCA-positive MPA were examined to determine the risk factors for relapse or infectious complications after remission induction therapy. Patients and methods: The study population consisted of 52 patients diagnosed as ANCA-positive MPA showing RPGN from 2002 to 2012, after publication of the Japanese guideline for RPGN. The clinicopathological findings were examined between the presence and absence of relapse or infectious complications. Results: The value of vasculitis damage index (VDI) was high for the relapse group and VDI value was identified as the leading factor associated with relapse [hazard ratio (HR) 3.36, 95 % confidence interval (CI) 1.58-7.12, P < 0.01]. On the other hand, the values of Birmingham Vasculitis Activity Score, clinical grade category of RPGN at diagnosis, and VDI at remission were high in the infectious group. Furthermore, clinical grade category of RPGN was the leading factor associated with infectious complications (HR 5.30, 95 % CI 1.41-19.9, P = 0.01). Conclusion: The disease activity at diagnosis and severity of organ damage at remission were associated with relapse and infectious complications during remission maintenance therapy and infectious complication affected kidney survival and all-cause mortality in patients with ANCA-positive MPA exhibiting RPGN. [ABSTRACT FROM AUTHOR]

Background: Renal coloboma syndrome (RCS) is characterized by renal anomalies and optic nerve colobomas. PAX2 mutations contribute to RCS. However, approximately half of the patients with RCS have no mutation in PAX2 gene. Methods: To investigate the incidence and effects of mutations of PAX2 and 25 candidate genes, patient genes were screened using next-generation sequence analysis, and candidate mutations were confirmed using Sanger sequencing. The correlation between mutations and clinical manifestation was evaluated. Result: Thirty patients, including 26 patients (two families of five and two, 19 sporadic cases) with RCS, and 4 optic nerve coloboma only control cases were evaluated in the present study. Six PAX2 mutations in 21 probands [28%; two in family cohorts (n = 5 and n = 2) and in 4 out of 19 patients with sporadic disease] including four novel mutations were confirmed using Sanger sequencing. Moreover, four other sequence variants (CHD7, SALL4, KIF26B, and SIX4) were also confirmed, including a potentially pathogenic novel KIF26B mutation. Kidney function and proteinuria were more severe in patients with PAX2 mutations than in those without the mutation. Moreover, the coloboma score was significantly higher in patients with PAX2 gene mutations. Three out of five patients with PAX2 mutations had focal segmental glomerulosclerosis (FSGS) diagnosed from kidney biopsies. Conclusion: The results of this study identify several new mutations of PAX2, and sequence variants in four additional genes, including a novel potentially pathogenic mutation in KIF26B, which may play a role in the pathogenesis of RCS. [ABSTRACT FROM AUTHOR]

Background: Some observational studies have shown the relationships between hyperuricemia and chronic kidney disease (CKD); however, the threshold of serum uric acid (SUA) for deterioration of kidney function and the association between SUA and kidney injury by baseline kidney function remains unclear. This study aimed to clarify the relationships between SUA and reduced kidney function. Methods: We analyzed a historical cohort of male Japanese individuals who underwent medical checkup between 1998 and 2007. Participants with baseline data and who were followed up for at least one year were included and stratified according to baseline kidney function. Kidney function was classified as normal [estimated glomerular filtration rate (eGFR) ≥ 90 ml/min/1.73 m2] or mildly reduced (eGFR 60–89 ml/min/1.73 m2). The outcome measured was kidney impairment defined as a decrease in eGFR to < 60 ml/min/1.73 m2. Associations between SUA and risk for outcome and eGFR slopes were assessed. Results: A total of 41632 subjects with mean age 45.4 years were included. During a mean follow-up of four years, 3186 (7.6%) subjects developed kidney dysfunction. Subjects with SUA ≥ 6.0 mg/dL had a significantly increased risk for kidney impairment compared with subjects with SUA of 4–4.9 mg/dL. SUA threshold levels were different according to baseline kidney function; SUA ≥ 7.0 and ≥ 6.0 mg/dL for normal and mildly reduced kidney function, respectively. Approximately the same trends were observed for eGFR slopes. Conclusion: In the general population, hyperuricemia appears to be a risk factor for kidney impairment in males. For participants with mild kidney dysfunction, even a slight elevation of SUA can be a risk factor. [ABSTRACT FROM AUTHOR]

Background: The prognosis in patients with idiopathic membranous nephropathy (IMN) is diverse. However, the prognosis after relapse and factors affecting relapse remain unclear. Methods: A total of 146 Japanese patients with IMN who had been followed up for at least 3 years, or until end-stage renal failure or death were enrolled in this retrospective study. The initial clinicopathological factors were examined between the patients with and without relapse. The patients were assigned to two groups based on the electron microscopic findings: homogeneous type with synchronous electron-dense deposits and heterogeneous type with various phases of dense deposits. Results: A total of 105 of the 146 patients (72 %) achieved complete remission (CR) or incomplete remission (ICR) I after initial treatment. Twenty-six of the 105 patients relapsed after CR or ICR I (25 %). There were no differences in initial clinical findings or data between the patients with and without relapse, except for the higher degree of proteinuria at onset in patients with relapse. The relapse rate of the heterogeneous group (43 %) was higher than that in the homogeneous group (20 %). There were no significant associations between relapse rate and immunosuppressive therapy at onset. Eleven of 26 patients showing relapse (42 %) achieved CR or ICR I, which was lower than the rate for patients with initial remission. Conclusion: Our results suggest that patients with relapse achieved CR or ICR I and that electron microscopic findings demonstrating heterogeneous type indicated susceptibility to relapse. [ABSTRACT FROM AUTHOR]

Diabetic nephropathy is a leading cause of end-stage renal disease in Japan. Microalbuminuria has been considered as the first clinical sign of diabetic nephropathy. However, recent studies demonstrated that normoalbuminuric renal insufficiency is not uncommon for diabetic patients, especially in type 2 diabetes. Although the pathogenesis of normoalbuminuric renal insufficiency in diabetic nephropathy remains to be fully elucidated, distinct clinical and pathological features of diabetic patients with this finding have been reported as compared to those in diabetic patients with a typical clinical course. In type 1 diabetes, more advanced glomerular lesions were found in patients with normoalbuminuric renal insufficiency than in patients with normoalbuminuric preserved renal function. In contrast, disproportionately advanced tubulointerstitial and vascular lesions, despite minor diabetic glomerular lesions, which denote the presence of diabetic kidney lesions as well as nephrosclerosis, were likely to be related to the development of normoalbuminuric renal insufficiency in some type 2 diabetic patients. In addition, long-term outcomes of diabetic patients with normoalbuminuric renal insufficiency remain controversial. Further studies to gain a better understanding of the structural-functional relationships and natural history of diabetic patients with normoalbuminuric renal insufficiency may improve the benefits of therapeutic interventions for diabetic nephropathy. [ABSTRACT FROM AUTHOR]

Highlights: [•] High glucose (HG) increases pro-inflammatory gene expression in renal resident cells. [•] Th2 related gene expression was down-regulated in renal resident cells with HG. [•] Signaling proteins shifted towards pro-inflammatory phenotype in renal resident cells. [•] HG shifts the immune balance to pro-inflammatory phenotype in diabetic nephropathy. [ABSTRACT FROM AUTHOR]

Background: The clinicopathological characteristics and outcome with pauci-immune crescentic glomerulonephritis (CreGN) are presumed to vary over time. We examined the characteristics and outcome of Japanese patients with CreGN according to the treatment periods. Patients and methods: From 1968 to 2011, we examined a total of 102 patients diagnosed with pauci-immune CreGN by renal biopsy. The patients were divided into three groups according to the treatment periods—Group I (1968–1988, n = 18), Group II (1989–2001, n = 37; when the nationwide survey of rapidly progressive glomerulonephritis [RPGN] was performed in Japan), and Group III (2002–2011, n = 47; after publication of the Japanese guideline for RPGN). Results: There were no significant differences in blood pressure, renal function or anti-neutrophil cytoplasmic antibody titer between groups. On the other hand, the rate of crescent formation and degree of interstitial inflammatory cell infiltration were decreased in Group III. Serum creatinine (<3.0, 3.0–6.0, ≥6.0 mg/dL) and crescent formation (<30, 30–50, 50–80, ≥80 %) were significant renal prognostic factors in Group III [serum creatinine: hazard ratio (HR) 4.79, 95 % confidence interval (CI) 1.43–16.1, P = 0.011; crescent formation: HR 2.86, 95 % CI 1.06–7.73, P = 0.039]. Furthermore, renal survival rate of patients with crescent formation <50 % and patient survival rate of patients with serum creatinine <3 mg/dL were improved in Group III. Conclusion: Patients with CreGN were diagnosed in the early phase of crescent formation and outcome has improved in recent years. [ABSTRACT FROM AUTHOR]

Background: Diabetic nephropathy, leading to end-stage renal disease, has a considerable impact on public health and the social economy. However, there are few national registries of diabetic nephropathy in Japan. The aims of this prospective cohort study are to obtain clinical data and urine samples for revising the clinical staging of diabetic nephropathy, and developing new diagnostic markers for early diabetic nephropathy. Methods: The Japanese Society of Nephrology established a nationwide, web-based, and prospective registry system. On the system, there are two basic registries; the Japan Renal Biopsy Registry (JRBR), and the Japan Kidney Disease Registry (JKDR). In addition to the two basic registries, we established a new prospective registry to the system; the Japan Diabetic Nephropathy Cohort Study (JDNCS), which collected physical and laboratory data. Results: We analyzed the data of 321 participants (106 female, 215 male; average age 65 years) in the JDNCS. Systolic and diastolic blood pressure was 130.1 and 72.3 mmHg, respectively. Median estimated glomerular filtration rate (eGFR) was 33.3 ml/min/1.73 m 2. Proteinuria was 1.8 g/gCr, and serum levels of albumin were 3.6 g/dl. The majority of the JDNCS patients presented with preserved eGFR and low albuminuria or low eGFR and advanced proteinuria. In the JRBR and JKDR registries, 484 and 125 participants, respectively, were enrolled as having diabetes mellitus. In comparison with the JRBR and JKDR registries, the JDNCS was characterized by diabetic patients presenting with low proteinuria with moderately preserved eGFR. Conclusions: There are few national registries of diabetic nephropathy to evaluate prognosis in Japan. Future analysis of the JDNCS will provide clinical insights into the epidemiology and renal and cardiovascular outcomes of type 2 diabetic patients in Japan. [ABSTRACT FROM AUTHOR]

Objective: We evaluated the structural-functional relationships and the prognostic factors for renal events, cardiovascular events, and all-cause mortality in type 2 diabetic patients with biopsy-proven diabetic nephropathy.Research Design and Methods: Japanese type 2 diabetic patients with biopsy-proven diabetic nephropathy (n = 260) were enrolled. Patients were stratified by albuminuria (proteinuria) and estimated glomerular filtration rate (eGFR) at the time of renal biopsy. The outcomes were the first occurrence of renal events (requirement of dialysis or a 50% decline in eGFR from baseline), cardiovascular events (cardiovascular death, nonfatal myocardial infarction, coronary interventions, or nonfatal stroke), and all-cause mortality.Results: The factors associated with albuminuria (proteinuria) regardless of eGFR were hematuria, diabetic retinopathy, low hemoglobin, and glomerular lesions. The factors associated with low eGFR regardless of albuminuria (proteinuria) were age and diffuse, nodular, tubulointerstitial, and vascular lesions. The glomerular, tubulointerstitial, and vascular lesions in patients with normoalbuminuria (normal proteinuria) and low eGFR were more advanced compared to those in patients with normoalbuminuria (normal proteinuria) and maintained eGFR. In addition, compared to patients with micro-/macroalbuminuria (mild/severe proteinuria) and low eGFR, their tubulointerstitial and vascular lesions were similar or more advanced in contrast to glomerular lesions. The mean follow-up period was 8.1 years. There were 118 renal events, 62 cardiovascular events, and 45 deaths. The pathological determinants were glomerular lesions, interstitial fibrosis and tubular atrophy (IFTA), and arteriosclerosis for renal events, arteriosclerosis for cardiovascular events, and IFTA for all-cause mortality. The major clinical determinant for renal events and all-cause mortality was macroalbuminuria (severe proteinuria).Conclusions: Our study suggests that the characteristic pathological lesions as well as macroalbuminuria (severe proteinuria) were closely related to the long-term outcomes of biopsy-proven diabetic nephropathy in type 2 diabetes. [ABSTRACT FROM AUTHOR]

Background: Precise effects of albuminuria and low estimated glomerular filtration rate (eGFR) on cardiovascular mortality, all-cause mortality, and renal events in diabetic patients are uncertain. Materials and Methods: A systematic review was conducted of the literature through MEDLINE, EMBASE, and CINHAL from 1950 to December 2010. Cohort studies of diabetic patients providing adjusted relative risk (RR) of albuminuria and eGFR for risks of cardiovascular mortality, all-cause mortality, and renal events were selected. Two reviewers screened abstracts and full papers of each study using standardized protocol. Results: We identified 31 studies fulfilling the criteria from 6546 abstracts. With regard to the risk of cardiovascular mortality, microalbuminuria (RR 1.76, 95%CI 1.38–2.25) and macroalbuminuria (RR 2.96 95%CI 2.44–3.60) were significant risk factors compared to normoalbuminuria. The same trends were seen in microalbuminuria (RR 1.60, 95%CI 1.42–1.81), and macroalbuminuria (RR 2.64, 95%CI 2.13–3.27) for the risk of all-cause mortality, and also in microalbuminuria (RR 3.21, 95%CI 2.05–5.02) and macroalbuminuria (RR 11.63, 95%CI 5.68–23.83) for the risk of renal events. The magnitudes of relative risks associated with low eGFR along with albuminuria were almost equal to multiplying each risk rate of low eGFR and albuminuria. No significant factors were found by investigating potential sources of heterogeneity using subgroup analysis. Conclusions: High albuminuria and low eGFR are relevant risk factors in diabetic patients. Albuminuria and low eGFR may be independent of each other. To evaluate the effects of low eGFR, intervention, or race, appropriately designed studies are needed. [ABSTRACT FROM AUTHOR]

The prevalence, clinical associations and pathogenic role of newly identified autoantibodies to the erythropoietin receptor ( EPOR) in patients with anaemia were investigated. Sera from 203 patients with immune-related or chronic kidney diseases were screened for anti- EPOR antibodies by enzyme-linked immunosorbent assay, and antibody specificity was evaluated by immunoprecipitating EPOR from AS- E2 cells using purified immunoglobulin ( Ig) fractions. In addition, the pathogenic role of anti- EPOR antibodies was determined by examining their inhibitory effects on AS- E2 cell proliferation. Clinical findings were compared between patients with and without anti- EPOR antibodies, in all patients and those with systemic lupus erythematosus ( SLE). Serum anti- EPOR antibodies were detected in 52 patients. Purified Ig G or Ig M fractions from anti- EPOR antibody-positive sera immunoprecipitated EPOR and inhibited the EPO-dependent proliferation of AS- E2 cells in a dose-dependent manner. Anti- EPOR antibodies were associated with low haemoglobin concentrations and reticulocytopenia in all patients enrolled and those with SLE. Further, there was a negative correlation between the levels of anti- EPOR antibodies and the number of bone marrow erythroblasts in patients who underwent bone marrow examinations. These findings suggest that EPOR autoantibodies are present in a subset of patients with anaemia and that impaired erythropoiesis can be mediated by anti- EPOR antibodies, which functionally neutralize EPO activity. [ABSTRACT FROM AUTHOR]

Background: Acute kidney injury (AKI) is a critical condition for kidney and other remote organs, including the lung. However, available treatments for AKI are limited. In this study, we explored the effect of adipose-derived mesenchymal cells on a mouse model of AKI. Methods: Adipose-derived mesenchymal cells were isolated from mouse subcutaneous and peritoneal adipose tissue by digestion with collagenase type I. The left renal artery and vein of C57BL/6 mice were clamped for 45 min to induce ischemia and were injected with the adipose-derived mesenchymal cells [1 × 10 cells/0.2 ml phosphate-buffered saline (PBS)] or 0.2 ml PBS via the tail vein on days 0, 1, and 2. Results: The adipose-derived mesenchymal cells had stem-cell surface markers and multilineage differentiating potentials. Administered adipose-derived mesenchymal cells homed primarily into lung. Interestingly, repeated administration of adipose-derived mesenchymal cells reduced acute tubular necrosis and interstitial macrophage infiltration in the injured kidney, accompanied with reduced cytokine and chemokine expression. Conclusion: Adipose-derived mesenchymal cells can be used as cell-based therapy for ischemic kidney injury. [ABSTRACT FROM AUTHOR]

Lupus nephritis (LN) is a major clinical manifestation of systemic lupus erythematosus (SLE). Although numerous abnormalities of immune system have been proposed, cytokine overexpression plays an essential role in the pathogenesis of LN. In the initial phase of the disease, the immune deposits and/or autoantibodies induce cytokine production in renal resident cells, leading to further inflammatory cytokine/chemokine expression and leukocyte infiltration and activation. Then, infiltrate leukocytes, such as macrophages (Mφ) and dendritic cells (DCs), secrete a variety of cytokines and activate naïve T cells, leading the cytokine profile towards T helper (Th)1, Th2, and/or Th17. Recent studies revealed these inflammatory processes in experimental animal models as well as human LN. The cytokine targeted intervention may have the therapeutic potentials for LN. This paper focuses on the expression of cytokine and its functional role in the pathogenesis of LN. [ABSTRACT FROM AUTHOR]

Objective: Myeloid-derived suppressor cells (MDSCs) have been identified as immunosuppressive cells in tumor-related inflammation. However, the pathogenesis of MDSCs for autoimmune disease has not been investigated as yet. The aim of this study was to address whether MDSCs contribute to autoimmune organ injury in lupus-prone mice. Methods: MDSCs were analyzed by flow cytometric staining of CD11b GR-1 in MRL- Fas mice. CD4 T-cell proliferation assay was performed by coculture with CD11b GR-1 splenocytes. The percentage of immunosuppressive cells was examined during disease progression. Expression of chemokine receptor on immunosuppressive cells was analyzed, and chemotaxis assay was performed. Results: CD11b GR-1 cells had a suppressive effect on CD4 T-cell proliferation, which was restored by an arginase-1 inhibitor. CD11b GR-1 cells increased in percentage during disease progression in kidney and blood. The number of migrated CD11b GR-1 cells increased in the presence of monocyte chemoattractant protein-1/CCL2. Conclusion: We assessed the involvement of CD11b GR-1 cells in autoimmune disorder in MRL- Fas mice. These cells regulate immunological responses via CCL2/CCR2 signaling. The regulation of immunosuppressive monocytes may provide novel therapeutic strategy for organ damage in autoimmune diseases. [ABSTRACT FROM AUTHOR]

Ischemia–reperfusion injury is a main cause of acute kidney injury. Tubular necrosis and interstitial inflammatory cell infiltration are characteristic pathologic changes of acute kidney injury. The main necrotic area should be repaired with new tubular epithelial cells after the injury. On the other hand, some parts of the injured kidney progress to interstitial fibrosis, a characteristic pathologic change in chronic kidney disease. We hypothesized that interstitial infiltrating leukocytes, that are attracted and activated by chemokines, are key mediators in the pathogenesis of tubular necrosis, regeneration of the necrotic area, or interstitial fibrosis. A large number of chemokines were upregulated after ischemic injury, and chemokine receptor-expressing inflammatory cells were attracted by these chemokines. Genetic or molecular modulating experiments in the mouse model have begun to reveal the key participants and their specific roles at the levels of inflammation, regeneration, and fibrosis. Among these chemokines/chemokine receptors, our data indicated CCR2-mediated macrophage infiltration mainly affected tubular necrosis after ischemic acute kidney injury, interferon-gamma-inducible protein (IP)-10-producing macrophages participate in regeneration of tubular epithelial cells, and CX3CR1-mediated macrophages and platelet infiltration and aggregation play roles in interstitial fibrosis in chronic kidney disease. These chemokines and chemokine receptors on infiltrating inflammatory cells would be novel clinical markers or targets for therapeutic intervention. [ABSTRACT FROM AUTHOR]

Although renal tubular cell proliferation after acute tubular necrosis is an important and essential response in the recovery of renal dysfunction in acute renal failure, the precise factors and mechanisms of tubular cell regeneration remain unclear. Here, we describe our studies using a neutralizing antibody (Ab) against interferon-inducible protein of 10 kDa (IP-10; CXCL10) that indicate a role for CXCL10 in tubular cell proliferation after renal ischemia-reperfusion injury. Tissue necrosis and interstitial infiltrating numbers were comparable between anti-CXCL10 Ab-treated and control mice treated with IgG at the 24 and 48 h time points after reperfusion. In contrast, the numbers of Ki67-positive proliferating tubular cells were significantly increased in anti-CXCL10 Ab-treated mice 48 h after reperfusion. In accordance with the in vivo findings,in vitro studies using murine tubular epithelial cells indicated an antiproliferative effect of CXCL10 upon the intensity of cell proliferation and the number of Ki67-positive cells. These data suggest that CXCL10 plays a role in the regulation of tubular cell proliferation following renal ischemia-reperfusion injury. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Focuses on the contribution of the inflammatory cascade to renal ischemia--reperfusion injury. Information that cytokines and chemokines participate in leukocyte migration to the diseased kidney; Information that hydrogen peroxide, which is the oxygen free radicals leaded after reperfusion injury directly activates p38 mitogen-activated protein kinase (MAPK); Claim that p38 MAPK is one of the key molecules involved in chemokine/cytokine production, which brings about the initiation of inflammation after reperfusion injury.

Kinesin family member 26b (Kif26b) is essential for kidney development, and its deletion in mice leads to kidney agenesis. However, the roles of this gene in adult settings remain elusive. Thus, this study aims to investigate the role of Kif26b in the progression of renal fibrosis. A renal fibrosis model with adenine administration using Kif26b heterozygous mice and wild‐type mice was established. Renal fibrosis and the underlying mechanism were investigated. The underlying pathways and functions of Kif26b were evaluated in an in vitro model using primary renal fibroblasts. Kif26b heterozygous mice were protected from renal fibrosis with adenine administration. Renal expressions of connective tissue growth factor (CTGF) and myofibroblast accumulation were reduced in Kif26b heterozygous mice. The expression of nonmuscle myosin heavy chain II (NMHCII), which binds to the C‐terminus of Kif26b protein, was also suppressed in Kif26b heterozygous mice. The in vitro study revealed reduced expressions of CTGF, α‐smooth muscle actin, and myosin heavy chain 9 (Myh9) via transfection with siRNAs targeting Kif26b in renal fibroblasts (RFB). RFBs, which were transfected by the expression vector of Kif26b, demonstrated higher expressions of these genes than non‐transfected cells. Finally, Kif26b suppression and NMHCII blockage led to reduced abilities of migration and collagen gel contraction in renal fibroblasts. Taken together, Kif26b contributes to the progression of interstitial fibrosis via migration and myofibroblast differentiation through Myh9 in the renal fibrosis model. Blockage of this pathway at appropriate timing might be a therapeutic approach for renal fibrosis. [ABSTRACT FROM AUTHOR]

Key Clinical Message: CYP3A4 and CYP3A5 are the most abundant and important enzymes of the CYP3A subfamily, distributed in the liver, intestinal mucosa and kidney, and involved in tacrolimus metabolism. Here, we report a case of tacrolimus dosage refractoriness due to a genetic polymorphism of CYP3A5. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Recently, hypoxia‐inducible factor prolyl hydroxylase (HIF‐PH) inhibitors have been used for renal anemia, but side effects have also been reported. We report on the association of central hypothyroidism and cholesterol with roxadustat. Based on this case and previous reports, we believe that patients receiving roxadustat should have their thyroid function and cholesterol levels checked regularly. [ABSTRACT FROM AUTHOR]

MIP-1α and MCP-1 contribute to crescents and interstitial lesions in human crescentic glomerulonephritis. Background. The precise molecular mechanisms of macrophage (Mφ) recruitment and activation in crescentic glomerulonephritis remain to be investigated. We hypothesized that locally produced macrophage inflammatory protein (MIP)-1α and monocyte chemoattractant protein (MCP)-1 via the chemokine receptors participate in the pathophysiology of human crescentic glomerulonephritis by recruiting and activating Mφ. Methods. We investigated the levels of MIP-1α and MCP-1 by enzyme-linked immunosorbent assay (ELISA) in 20 healthy subjects, 20 patients with crescentic glomerulonephritis, and 41 control patients with various other renal diseases. The presence of MIP-1α, MCP-1, and the cognate chemokine receptor for MIP-1α, CCR5, in the diseased kidneys was evaluated by immunohistochemical and in situ hybridization analyses. Results. MIP-1α–positive cells were mainly detected in crescentic lesions, whereas MCP-1 was mainly in the interstitium. In addition, we detected CCR5-positive cells in diseased glomeruli and interstitium. Urinary MIP-1α was detected in crescentic glomerulonephritis, even though it was below detectable levels in healthy subjects and in patients with other renal diseases without crescents. Urinary MIP-1α levels in the patients with crescentic glomerulonephritis were well correlated with the percentage of cellular crescents and the number of CD68-positive infiltrating cells and CCR5-positive cells in the glomeruli. However, urinary MCP-1 levels were well correlated with the percentage of both total crescents and fibrocellular/fibrous crescents and the number of CD68-positive infiltrating cells in the interstitium. Moreover, elevated urinary levels of both MIP-1α and MCP-1 dramatically decreased during glucocorticoid therapy-induced convalescence. Conclusions. These observations suggest that... [ABSTRACT FROM AUTHOR]

Background: Patients with nephrosclerosis display heterogenous clinical phenotypes, often leading to a clinical diagnosis discordant with pathological nephrosclerosis diagnosis. However, little is known about clinical factors associated with clinicopathological discordance of biopsy-proven nephrosclerosis. Methods: In a cross-sectional study of 891 patients with biopsy-proven nephrosclerosis registered in the Japan Renal Biopsy Registry (J-RBR) between July 2007 and June 2016, we examined clinical characteristics associated with a pre-biopsy clinical diagnosis discordant with pathological nephrosclerosis diagnosis using multivariable logistic regression with adjustment for relevant clinical characteristics. Results: Overall, the mean (SD) age was 58.6 (13.7) years; 67.6% of patients were male; and 63.2% were on antihypertensive drugs. The median estimated glomerular filtration rate (eGFR) was 43.8 mL/min/1.73 m2 and the median proteinuria was 0.5 g/day. Of the 891 patients, 497 (55.8%) had a clinical diagnosis discordant with pathological nephrosclerosis diagnosis, with chronic nephritic syndrome being the most common (> 75%) discordant clinical diagnosis. After multivariable adjustment, age (odds ratio 1.34, [95% confidence interval, 1.16–1.55], per 10 years increase), eGFR (1.10 [1.00–1.21], per 10 mL/min/1.73 m2 increase), and proteinuria (1.20 [1.03–2.16], per 1 g/day decrease) were found to be significantly associated with the clinicopathological discordance. Conclusions: Patients with older age, higher eGFR, and lower proteinuria had significantly higher likelihood of being clinically diagnosed with other glomerular disease in patients with biopsy-proven nephrosclerosis. Our findings highlight the heterogeneous clinical phenotypes of nephrosclerosis and suggest the need for continuous improvement of clinical diagnostic accuracy as well as for wider kidney biopsy indications for nephrosclerosis. [ABSTRACT FROM AUTHOR]

Key Clinical Message: Pleomorphic lung cancer is a very rare type of cancer and very few cases have been reported in the literature. We present a case of pleomorphic lung cancer in a patient with history of IgA nephropathy on hemodialysis. [ABSTRACT FROM AUTHOR]

Background: The guidelines in Japan for the treatment of rapidly progressive glomerulonephritis (RPGN) have been revised; the latest update was released in 2020. We investigated the actual usage of the new guidelines in Japan. Methods: We distributed a survey electronically to board-certified nephrologists throughout Japan from December 15, 2021 to January 31, 2022. The survey focused on anti-neutrophil cytoplasmic antibody (ANCA)-associated RPGN and anti-glomerular basement membrane (GBM)-antibody RPGN, plus the treatment strategies and infection-prevention measures used. Results: The survey was completed by 155 certified nephrologists from medical facilities across Japan. Their responses regarding treatment procedures revealed that ANCA-associated RPGN was treated with immunosuppressants and/or biologics by 58.1% of the survey respondents, and with plasma exchange (PE) in combination with corticosteroids by 21.3%. Regarding anti-GBM-antibody RPGN, 78.1% of the respondents used corticosteroids in combination with PE (63.2%), cyclophosphamide (CY) (23.9%), or rituximab (RTX) (8.4%), suggesting a discrepancy between clinical practice and the actual use of the guidelines. Trimethoprim-sulfamethoxazole was prescribed as prophylaxis by 94.8% of the respondents, reflecting the widespread recognition of the need to prevent infectious disease in patients with RPGN. Conclusions: The survey responses revealed how Japan's new RPGN guidelines are used in actual clinical practice. Our findings will contribute to the guidelines' dissemination and implementation. [ABSTRACT FROM AUTHOR]

Collagen type VI (COL6) deposition occurs in various glomerular diseases, causing serious pathological damage like nodular lesions. However, the mechanisms underlying the deposition of COL6 remain unclear. In renal biopsy samples, immunohistochemical analyses revealed that COL6 and phosphorylated histone H2AX (γ-H2AX), a DNA damage marker, were detected mainly in diabetic nodular glomerulosclerosis, in which the γ-H2AX-positive area was identified as the independent factor significantly associated with the COL6-positive area (β: 0.539, t = 2.668). In in vitro studies, COL6 secretion from human renal glomerular endothelial cells (HRGECs) was assessed by measuring the decrease in the cytoplasmic COL6-positive cells and an increase in the amount of COL6 in the culture medium. Mitomycin C (MMc) treatment of HRGECs increased the number of γ-H2AX-positive cells and COL6 secretion, which were suppressed by a specific inhibitor of ataxia telangiectasia and Rad3-related (ATR). MMc-induced COL6 secretion was also suppressed by Annexin A2 (ANXA2) siRNA transfection. Moreover, the inhibition of ATR activity did not induce any extra suppression in the MMc-induced COL6 secretion by ANXA2 siRNA transfected cells. These results confirm that nodular glomerulosclerosis partially results from DNA damage in the glomerulus and that DNA damage-induced COL6 secretion from HRGECs occurs through an ATR and ANXA2-mediated pathway. [ABSTRACT FROM AUTHOR]

• Gene mutations that correlated with clinical manifestations of MRSA were analyzed. • The mutation on cna locus were associated with a high frequency of BSI. • Mutant CNA protein showed lower attachment ability to collagen. • The mutant CNA might contribute to the dissemination of MRSA, thereby causing BSI. Methicillin-resistant Staphylococcus aureus (MRSA) causes hospital- and community-acquired infections. It is not clear whether genetic characteristics of the bacteria contribute to disease pathogenesis in MRSA infection. We hypothesized that whole genome analysis of MRSA strains could reveal the key gene loci and/or the gene mutations that affect clinical manifestations of MRSA infection. Whole genome sequences (WGS) of MRSA of 154 strains were analyzed with respect to clinical manifestations and data. Further, we evaluated the association between clinical manifestations in MRSA infection and genomic information. WGS revealed gene mutations that correlated with clinical manifestations of MRSA infection. Moreover, 12 mutations were selected as important mutations by Random Forest analysis. Cluster analysis revealed strains associated with a high frequency of bloodstream infection (BSI). Twenty seven out of 34 strains in this cluster caused BSI. These strains were all positive for collagen adhesion gene (cna) and have mutations in the locus, those were selected by Random Forest analysis. Univariate and multivariate analysis revealed that these gene mutations were the predictor for the incidence of BSI. Interestingly, mutant CNA protein showed lower attachment ability to collagen, suggesting that the mutant protein might contribute to the dissemination of bacteria. These findings suggest that the bacterial genotype affects the clinical characteristics of MRSA infection. [ABSTRACT FROM AUTHOR]

The nationwide clinical features of Japanese patients with primary nephrotic syndrome (NS), including minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), or membranous nephropathy (MN), have not yet been reported. We collected the clinical personal records of patients with primary NS between 2015 and 2018 from the national registry organized by the Japanese Ministry of Health, Labour, and Welfare. Overall, the demographics, chronic kidney disease classification based on glomerular filtration rate and albuminuria, and treatment of 6036 patients were collected: 3394 (56.2%) with MCD, 677 (11.2%) with FSGS, 1455 (24.1%) with MN, and 510 (8.5%) with others. MN patients were older than MCD and FSGS patients (67 vs. 42 and 47 years, respectively). Steroid-dependent NS or frequently relapsing NS was found in 70.2%, 40.5%, and 24.6%, whereas steroid-resistant NS was found in 6.4%, 36.0%, and 37.9% of patients in the MCD, FSGS, and MN, respectively. The present oral prednisolone use (mean dose, mg/day) was 87.2% (21.2), 80.9% (20.0), and 77.5% (18.8) of patients in the MCD, FSGS, and MN, respectively. The national registry of clinical personal records of primary NS could provide an informative insight into the characteristics, clinical features, and treatment approaches for patients with primary NS in Japan. [ABSTRACT FROM AUTHOR]

Background: Rectus sheath hematoma is a rare presentation often associated with abdominal trauma and anticoagulant therapy. Here, we present a patient with severe rectus sheath hematoma accompanied by nephrotic syndrome who achieved significant clinical improvement without the need for invasive treatment. Case presentation: A 72-year-old Japanese woman was referred to our hospital for the treatment of nephrotic syndrome. She was receiving steroid and anticoagulant therapy. Then she had abdominal pain and she was diagnosed with spontaneous rectus sheath hematoma by abdominal computed tomography. She received transfusion and was managed conservatively with bed rest, which led to improvement in abdominal pain. Conclusion: Despite the absence of trauma history, rectus sheath hematoma should be considered in patients at risk of vascular failure, including those receiving anticoagulant or steroid therapy, those who are elderly, and those with nephrotic syndrome. [ABSTRACT FROM AUTHOR]

The nationwide clinical features of Japanese patients with primary nephrotic syndrome (NS), including minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), or membranous nephropathy (MN), have not yet been reported. We collected the clinical personal records of patients with primary NS between 2015 and 2018 from the national registry organized by the Japanese Ministry of Health, Labour, and Welfare. Overall, the demographics, chronic kidney disease classification based on glomerular filtration rate and albuminuria, and treatment of 6036 patients were collected: 3394 (56.2%) with MCD, 677 (11.2%) with FSGS, 1455 (24.1%) with MN, and 510 (8.5%) with others. MN patients were older than MCD and FSGS patients (67 vs. 42 and 47 years, respectively). Steroid-dependent NS or frequently relapsing NS was found in 70.2%, 40.5%, and 24.6%, whereas steroid-resistant NS was found in 6.4%, 36.0%, and 37.9% of patients in the MCD, FSGS, and MN, respectively. The present oral prednisolone use (mean dose, mg/day) was 87.2% (21.2), 80.9% (20.0), and 77.5% (18.8) of patients in the MCD, FSGS, and MN, respectively. The national registry of clinical personal records of primary NS could provide an informative insight into the characteristics, clinical features, and treatment approaches for patients with primary NS in Japan. [ABSTRACT FROM AUTHOR]

Background: With the publication of the "Evidence-Based Clinical Practice Guideline for Nephrotic Syndrome 2020," we examined nephrologists' adherence to the recommendations of four of its clinical questions (CQs). Methods: This was a cross-sectional web-based survey conducted between November and December 2021. The target population comprised nephrologists certified by the Japanese Society of Nephrology who were recruited using convenience sampling. The participants answered six items regarding the four CQs about adult patients with nephrotic syndrome and their characteristics. Results: In total, 434 respondents worked in at least 306 facilities, of whom 386 (88.9%) provided outpatient care for primary nephrotic syndrome. Of these patients, 179 (41.2%) answered that they would not measure anti- phospholipase A2 receptor antibody levels in cases of suspected primary membranous nephropathy (MN) in which kidney biopsy was not possible (CQ1). Regarding immunosuppressants as maintenance therapy after relapse of minimal change nephrotic syndrome (CQ2), cyclosporine was the most common choice (290 [72.5%] and 300 [75.0%] of 400 respondents after the first and second relapses, respectively). The most common treatment for steroid-resistant cases of primary focal segmental glomerulosclerosis (CQ3) was cyclosporine (323 of 387, 83.5%). For the initial treatment of primary MN with nephrotic-range proteinuria (CQ4), corticosteroid monotherapy was the most common choice (240 of 403, 59.6%), followed by corticosteroid and cyclosporine (114, 28.3%). Conclusion: Gaps in recommendations and practices regarding serodiagnosis and treatment of MN (i.e., CQ1 and 4) are observed, suggesting the need to address the barriers to their insurance reimbursement and the lack of evidence behind them. [ABSTRACT FROM AUTHOR]

Association rule is a transparent machine learning method expected to share information about risks for chronic kidney disease (CKD) among diabetic patients, but its findings in clinical data are limited. We used the association rule to evaluate the risk for kidney disease in General and Worker diabetic cohorts. The absence of risk factors was examined for association with stable kidney function and worsening kidney function. A confidence value was used as an index of association, and a lift of > 1 was considered significant. Analyses were applied for individuals stratified by KDIGO's (Kidney Disease: Improving Global Outcomes) CKD risk categories. A General cohort of 4935 with a mean age of 66.7 years and a Worker cohort of 2153 with a mean age of 47.8 years were included in the analysis. Good glycemic control was significantly related to stable kidney function in low-risk categories among the General cohort, and in very-high risk categories among the Worker cohort; confidences were 0.82 and 0.77, respectively. Similar results were found with poor glycemic control and worsening kidney function; confidences of HbA1c were 0.41 and 0.27, respectively. Similarly, anemia, obesity, and hypertension showed significant relationships in the low-risk General and very-high risk Worker cohorts. Stratified risk assessment using association rules revealed the importance of the presence or absence of risk factors. [ABSTRACT FROM AUTHOR]

Introduction: Treating diabetic nephropathy with low-density lipoprotein (LDL) apheresis reduces proteinuria and improves prognosis. However, its impact on patients' quality of life (QoL) is unclear. This study evaluated the effect of LDL apheresis on QoL in patients with diabetes, proteinuria, and hypercholesterolemia. Methods: In this nationwide multicenter prospective study, we enrolled 40 patients with diabetes. Inclusion criteria were proteinuria (defined as an albumin/creatinine ratio ≥3 g/g), serum creatinine levels <2 mg/dL, and serum LDL ≥120 mg/dL despite drug treatment. LDL apheresis was performed 6–12 times within 12 weeks. The 36-item Short Form Health Survey (SF-36) was used to analyze QoL. Results: The study enrolled 35 patients (27 men and 8 women; mean age 58.9 ± 11.9 years). A comparison of baseline SF-36 values with those at the end of the course of apheresis found an improvement in the mean physical component summary (37.9 ± 11.4 vs. 40.6 ± 10.5, p = 0.051) and a significant increase in the mean mental component summary (MCS) (49.4 ± 8.4 vs. 52.5 ± 10.9, p = 0.026). A multivariable linear regression analysis revealed a history of coronary heart disease negatively correlated with the MCS increase at the end of the course of apheresis (β coefficient −6.935, 95% confidence interval, 13.313 to−0.556, p = 0.034). Conclusion: Our results suggest that LDL apheresis may improve the mental and physical QoL in patients with diabetes, proteinuria, and hypercholesterolemia. [ABSTRACT FROM AUTHOR]

Background: Apoptosis inhibitor of macrophage (AIM) expressed on macrophages prolongs inflammation by protecting macrophages from apoptosis. Most circulating AIM co-exists with immunoglobulin M (IgM). AIM's pathophysiological role in relation to IgM remains unclear. Here we evaluated the glomerular expression/deposition of AIM and IgM in the kidney using immunohistochemistry and its associations with clinical manifestations in 43 patients with biopsy-confirmed kidney diseases. Methods: Kidney biopsy tissue from all patients was immunostained for AIM and IgM. Staining patterns and percent stained areas within the glomeruli were determined. Cells expressing AIM were identified by co-staining with macrophage and endothelial cell surface markers. Correlations between staining results and clinical parameters were evaluated using univariate and multivariate analyses. Results: AIM was deposited in various areas, such as mesangial and capillary area. A part of AIM expression was localized to CD68-positive macrophages in the glomerulus. Amount of glomerular expression was positively correlated with urinary protein in patients with severe proteinuria (urinary protein ≥0.5 g/day) and kidney dysfunction [estimated glomerular filtration ratio (eGFR) <60 ml/min/1.73 m]. Urinary protein was higher in patients exhibiting overlapping glomerular expression of AIM and IgM. Annual eGFR decline rate negatively correlated with AIM-positive area. AIM-positive area and initial serum creatinine were independently associated with decreased kidney function. Conclusion: AIM expression in the kidney was associated with urinary protein and decline in kidney function. Co-expression with IgM appeared to exacerbate AIM's deleterious effects on kidney function. Combined glomerular AIM and IgM expression is a candidate prognostic index for kidney disease. [ABSTRACT FROM AUTHOR]

We analyzed the seasonal variations in the number of renal biopsies and clinical characteristics of primary glomerular disease in Japan using the Japan Renal Biopsy Registry (J-RBR). We retrospectively collected clinical and pathological data of patients with primary glomerular disease who were registered in the J-RBR between 2007 and 2018. Immunoglobulin A nephropathy (IgAN), minimal change nephrotic syndrome (MCNS), membranous nephropathy (MN), and postinfectious acute glomerulonephritis (PIAGN) constituted the four major glomerular disorders included in this study (total, 13,989; IgAN, 9121; MCNS, 2298; MN, 2447; and PIAGN, 123). The number of patients with IgAN or MCNS was higher during summer. However, no overt seasonal variations were observed in patients with MN or PIAGN. Subgroup analyses suggested that in the patients with IgAN, more renal biopsies of severe cases were performed during winter, probably owing to age and blood pressure. Furthermore, more renal biopsies of severe cases were performed during spring and winter in patients with MCNS even after adjusting for the abovementioned host factors. This study suggests that seasonal factors influence the decision to perform renal biopsy as well as the pathogenesis of primary glomerular disease. Thus, our findings may provide important insights regarding the pathophysiology of primary glomerular disease. [ABSTRACT FROM AUTHOR]

Background: This study investigated the sex differences in the risk of end‐stage kidney disease (ESKD) and mortality, as well as the effect modification of sex on associated factors in patients with type 2 diabetes. Methods: This multicenter observational cohort study included 4328 patients with type 2 diabetes. Hazard ratios (HRs) with 95% confidence intervals (CIs) of sex for ESKD and death were estimated using Cox proportional regression with adjustment for baseline covariates. For assessing risk modification, HRs and incidence rates for ESKD and death were compared between sexes across patient characteristics using Cox proportional and Poisson regression models. Results: During a median follow‐up of 7 years, 276 patients (70% men) developed ESKD, and 241 patients (68% men) died. Men had higher risks of ESKD (HR 1.34; 95% CI 1.02–1.75; p =.034) and death (HR 1.64; 95% CI 1.24–2.16; p =.001) versus women after adjusting for multiple covariates. Among patients with microalbuminuria, men had a substantially higher risk of ESKD versus women, compared to those with normo‐ and macroalbuminuria (p for interaction.04). Incidence rates were also increased in men versus women with albuminuria of around 300 mg/g. No differences were detected in the association of sex and death across baseline patient subgroups. Conclusions: In type 2 diabetes, men had an increased risk of ESKD and death versus women. Moderately increased albuminuria was strongly associated with sex difference in developing ESKD. [ABSTRACT FROM AUTHOR]

Examines the role of monocyte chemoattractant protein-1 (MCP-1) in progressive glomerular and interstitial damage in inflammatory renal diseases. Expression of MCP-1 in diabetic nephropathy; Elevation of urinary MCP-1 levels in patients with diabetic nephropathy; Formation of tubulointerstitial lesions.

Background: Various sleep abnormalities, such as delayed sleep onset, frequent awakening and daytime sleepiness, deteriorate the quality of life in patients with chronic kidney disease (CKD), including those on haemodialysis (HD). Although there are some candidate causative molecules in the central nervous system, the contribution of peripheral blood cells (PBCs) remains unclear. In this study, we performed polysomnographic analysis in CKD patients and used PBCs to examine the expression of genes related to sleep and wakefulness states. Methods: Polysomnographic analysis was performed in 9 CKD patients and 6 controls. Genes related to sleep and wakefulness were evaluated by RNA microarray in 19 subjects, including CKD patients and control subjects. Results: Polysomnographic analysis revealed that the duration of the rapid eye movement (REM)/non-REM phases during total sleep time was different between CKD patients and healthy controls. In mRNA microarray evaluation, hierarchical clustering analysis showed different patterns of sleep-related gene expression in HD patients. mRNA expression levels of GABA receptor (GABBR2), noradrenaline receptor (ADRA1A), dopamine receptor (DRD1) and histamine receptor (HRH1) showed an inverse correlation with renal function. Moreover, the mRNA expression of orexin and its receptor (HCRTR1 and HCRTR2) was also inversely correlated with renal function. Conclusion: These data indicate that the expression of sleep-related genes in PBCs of CKD patients may be associated with sleep abnormalities. [ABSTRACT FROM AUTHOR]

Background: Carotid echo indexes [intima-media thickness (IMT)] are commonly used surrogate markers for cardiovascular disease; however, the impacts of chronic kidney disease (CKD) on changes in IMT are unclear. We examined associations between CKD and IMT in participants with and without type 2 diabetes through longitudinal analysis. Methods: In total, 424 subjects were enrolled in this study. IMT was measured as per carotid echo indexes. Relationships between IMT and risk factors were analyzed using multiple linear regression analysis, in which we defined IMT as the dependent variable and atherosclerosis-related factors (age, sex, systolic pressure, total cholesterol, body mass index, estimated glomerular filtration rate (eGFR), uric acid, smoking index, number of antihypertensive drugs, statin use, urinary protein levels, past cardiovascular event, glycated hemoglobin, and diabetes duration) as independent variables. Results: The study population was composed of 70.3 % male subjects. Participants with diabetes accounted for 64.4 % of the total population. The mean follow-up duration was 2.2 ± 1.5 years. Alterations in IMT tended to be associated with systolic blood pressure (+10 mmHg) ( β = −0.0084, p = 0.09) and eGFR (+10 mL/min/1.73 m) ( β = −0.0049, p = 0.06) in all participants. In participants without diabetes, alterations in IMT were associated with eGFR (+10 mL/min/1.73 m) ( β = −0.0104, p = 0.03) and tended to be associated with systolic blood pressure (+10 mmHg) ( β = 0.0094, p = 0.06). No significant relationships were found in participants with diabetes. Conclusion: Low eGFR was associated with progression of carotid thickness independent of common cardiovascular risk factors in non-diabetic participants. [ABSTRACT FROM AUTHOR]

This retrospective exploratory study aimed to identify early clinical indicators of kidney prognosis in primary nephrotic syndrome (NS). Univariate Cox proportional hazards regression analysis identified clinical parameters in the 2-month period after initiating immunosuppressive therapy (IST); it predicted 40% reduction in the estimated glomerular filtration rate (eGFR) in 36 patients with primary NS. Time-dependent receiver operating characteristic curve analysis was used to evaluate the performance of the predictors for the cumulative incidence of 40% reduction in the eGFR up to 8 years after initiating IST. The mean follow-up period was 71.9 months. The eGFR was reduced by 40% in four patients. Significant predictors for time to 40% reduction in the eGFR were as follows: an increase in the serum soluble urokinase plasminogen activator receptor (s-suPAR) 2 months after initiating IST (Δs-suPAR (2M); hazard ratio (HR) for every 500 pg/mL increase: 1.36, P = 0.006), s-suPAR at 2 months after initiating IST (s-suPAR (2M); HR for every 500 pg/mL increase: 1.13, P = 0.015), urinary protein-to-creatinine ratio (u-PCR) (u-PCR (2M); HR for every 1.0 g/gCr increase: 2.94, P = 0.003), and urinary liver-type fatty acid-binding protein (u-L-FABP) (u-L-FABP (2M); HR for every 1.0 μg/gCr increase: 1.14, P = 0.006). All four factors exhibited high predictive accuracy for cumulative incidence of 40% reduction in the eGFR up to 8 years after initiating IST, with areas under the receiver operating characteristic curve of 0.92 for Δs-suPAR (2M), 0.87 for s-suPAR (2M), 0.93 for u-PCR (2M), and 0.93 for u-L-FABP (2M). These findings suggest that Δs-suPAR (2M), s-suPAR (2M), u-PCR (2M), and u-L-FABP (2M) could be useful indicators of initial therapeutic response for predicting kidney prognosis in primary NS. [ABSTRACT FROM AUTHOR]