Glomerular Diseases Across Lifespan: Key Differences in Diagnostic and Therapeutic Approaches.

Glomerular diseases are common causes of chronic kidney disease in childhood, adolescence, and adulthood. The epidemiology of glomerular diseases differs between different age groups, with minimal change disease being the leading cause of nephrotic syndrome in childhood, while membranous nephropathy and focal segmental glomerulosclerosis are more common in adulthood. IgA vasculitis is also more common in childhood. Moreover, there is a difference in disease severity with more children presenting with a relapsing form of nephrotic syndrome and a more acute presentation of antineutrophil cytoplasmic antibody-associated vasculitis and concomitant glomerulonephritis, as highlighted by the higher percentage of cellular crescents on kidney biopsy specimens in comparison with older patients. There is also a female preponderance in antineutrophil cytoplasmic antibody-associated vasculitis and more children present with tracheobroncholaryngeal disease. This article aims to summarize differences in the presentation of different glomerular diseases that are encountered commonly by pediatric and adult nephrologists and potential differences in the management.

[Frequency of glomerular diseases in an analysis of 550 kidney biopsies]. / Caracterización de enfermedades glomerulares: análisis de 22 años de biopsias renales.

BACKGROUND: The frequency of glomerular diseases is dynamic and varies according to geographic area. AIM: To evaluate the frequency of primary and secondary glomerulopathies, their demographic profile and main clinical characteristics. MATERIAL AND METHODS: Renal biopsies from native kidneys performed between 1999 and 2020 were retrospectively reviewed. Demographic characteristics, clinical presentation, most relevant laboratory tests, frequency of primary and secondary glomerulopathies were analyzed. RESULTS: We analyzed 550 kidney biopsies from patients with a median age of 48 years (64% females). Nephrotic syndrome was the main indication for renal biopsy. Primary and secondary glomerulopathies occurred with similar frequency. Within the primary glomerulopathies, membranous nephropathy (34.1%) was the most common, followed by IgA nephropathy (31.1%) and focal segmental glomerulosclerosis (14.1%). Among the secondary glomerulopathies, lupus nephropathy was the most common (41.7%), followed by pauciimmune glomerulonephritis (27.1%) and diabetic nephropathy (6.4%). When comparing the results with other regions, significant differences were observed with reported frequencies in United States, Europe, Asia and the rest of Latin America. CONCLUSIONS: The most common primary glomerulopathies were membranous nephropathy and IgA nephropathy. Among the secondary glomerulopathies lupus nephropathy and pauci-immune glomerulonephritis were the most common. Compared to international registries, we observed a high proportion of membranous nephropathy and pauci-immune glomerulonephritis.

Changes in spectrum of biopsy-proven kidney diseases within decade: an analysis based on 10 199 cases from South China.

PURPOSE: To assess the regional epidemiological trends of kidney diseases over time in the South China using renal biopsy-proven cases. METHODS: This retrospective observational cohort study was conducted at the Institute of Nephrology, Second Xiangya Hospital of Central South University, and encompasses all patients diagnosed with kidney disease via biopsy from 2012 to 2021. RESULTS: The study sample consisted of 10 199 native kidneys, with a male-to-female ratio of 0.91:1 and an average age of 38.74 (±14.53) years. Primary glomerular nephropathy, systemic glomerular nephropathy (SGN), tubulointerstitial disease, and hereditary renal diseases accounted for 66.92 (6825)%, 24.49 (2498)%, 8.06 (822)%, and 0.53 (54)%, respectively. The leading pathologies of primary glomerular nephropathy remained the IgA nephropathy. The frequencies of IgA nephropathy and membranous nephropathy increased significantly, whereas the frequencies of minimal change disease and focal segmental glomerulosclerosis decreased (P < .001) between 2017 and 2021 than in the years 2012 and 2016. An earlier onset of membranous nephropathy was observed in the age group of 45-59 years compared to previous studies. The leading pathologies of SGN were found to be lupus nephritis (758 cases, 30.45%) and hypertension nephropathy (527 cases, 21.17%). The frequencies of hypertension nephropathy and diabetic nephropathy increased between 2017 and 2021 compared to 2012 and 2016 (P < .001), gradually becoming the leading pathological types of SGN. In elderly patients diagnosed with nephrotic syndrome, the frequencies of amyloidosis significantly increased (P < .01). CONCLUSION: Our study may provide insights for kidney disease prevention and public health strategies. What is already known on this topic The pathological spectrum of kidney diseases has undergone significant transformations in the past decade, driven by the escalating incidence of chronic diseases. Although there are studies exploring the renal biopsy findings from various regions in China which present both similarities and differences in epidemiology, few large-scale reports from the South China in recent decades were published. What this study adds Our findings reveal the following key observations: (i) increased proportion of middle-aged patients leading to the increasing average age at the time of biopsy；(ii) the frequencies of IgA nephropathy and membranous nephropathy (MN) increased significantly, whereas the frequencies of minimal change disease and focal segmental glomerulosclerosis decreased (P < .001) between 2017 and 2021 than in the years 2012 and 2016; (iii) earlier onset of MN in the age group of 45-59 years old was found in our study; and (iv) a higher frequency of hypertension nephropathy and DN presented over time, and frequency of amyloidosis increased in elderly patients diagnosed with NS. How this study might affect research, practice, or policy This single-center yet a large-scale study of the kidney disease spectrum in South China may provide a reference point for the diagnosis, treatment, and prevention of chronic kidney disease.

Demographics and treatment of patients with primary nephrotic syndrome in Japan using a national registry of clinical personal records.

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.

Renal pathology in adult and paediatric population of Japan: review of the Japan renal biopsy registry database from 2007 to 2017.

BACKGROUND: The Japan Renal Biopsy Registry (J-RBR), a nationwide, web-based, registry system, started in 2007. This study aimed to summarise the epidemiology of biopsy-diagnosed kidney disease in Japan over 10 years. METHODS: We analysed the J-RBR database, from 2007 to 2017. Patients' clinical data collected at the time of biopsy and histopathological diagnoses were used for epidemiological and clinicopathologic analyses. RESULTS: The predominant renal biopsy diagnoses were immunoglobulin A nephropathy (39.2%), lupus nephritis (6.5%) and minimal change disease (6.0%) in younger adults (19-64 years), and membranous nephropathy (17.4%), antineutrophil cytoplasmic antibody-associated vasculitis or anti-glomerular basement membrane glomerulonephritis (13.0%), and immunoglobulin A nephropathy (12.5%) in older adults (≥ 65 years). The percentages of patients diagnosed with membranoproliferative glomerulonephritis and immunoglobulin A nephropathy decreased, whereas those with immunoglobulin A vasculitis and diabetic nephropathy increased over the decade. In paediatric patients (< 19 years), immunoglobulin A nephropathy (36.1%), minimal change disease (17.6%), and immunoglobulin A vasculitis (8.6%) were the predominant diagnoses. The percentage of patients diagnosed with immunoglobulin A vasculitis increased over the decade. Based on the sex distribution, minimal change disease and membranous nephropathy were predominant in men aged < 20 and > 40 years, respectively, whereas immunoglobulin A vasculitis and antineutrophil cytoplasmic antibody-associated vasculitis or anti-glomerular basement membrane glomerulonephritis were predominant in women in their 20s and 30s and aged < 50 years, respectively. Immunoglobulin A nephropathy was predominant in men at most ages and in women in their 20s to 40s. CONCLUSIONS: This study describes the distribution and changes in kidney biopsy diagnoses over 10 years in Japan and paves the way for future research on kidney diseases in adults and children.

Lower limb arterial thrombosis in an adult with membranous glomerulonephritis.

Massive proteinuria and hypoalbuminemia are potential risk factors in thromboembolic complications. Venous thrombosis is a frequent complication of thromboembolism in patients with membranous glomerulonephritis, while arterial thrombosis is much less reported. A 35-year-old man presented with nephrotic syndrome and osteofascial compartment syndrome in the right lower limb due to arterial thrombosis. The biopsy findings were consistent with those of stage 2 membranous nephropathy. After immunotherapy (steroids and cyclosporine), the massive proteinuria, renal function, and serum albumin improved markedly. This is the first case of adult membranous glomerulonephritis with unilateral lower extremity arterial thrombosis diagnosed by renal biopsy and arteriography. It further confirms the high incidence of thromboembolic complications with membranous nephropathy.

Prognosis and incidence of infections in chronic kidney disease patients with membranous nephropathy enrolled in a large Japanese clinical claims database.

BACKGROUND: The treatment of membranous nephropathy involves a combination of conservative approaches, steroids, and immunosuppressive agents. Infection is an adverse effect of these treatments and its incidence is a critical issue for patients with membranous nephropathy, as many of them are older adults. However, the incidence of infections remains unclear; hence, this study investigated this issue using data from a large Japanese clinical claims database. METHODS: From a database of patients with chronic kidney disease (n = 924,238), those diagnosed with membranous nephropathy from April 2008 to August 2021 with a history of one or more prescriptions and undergoing medical care were included. Patients who had undergone kidney replacement therapy were excluded. Patients were divided into three groups based on their prescriptions after diagnosis: prednisolone(PSL), who received steroids; PSL + IS, who were prescribed steroids and immunosuppressive agents; and C, who were treated without steroid or immunosuppressive agent use. The primary outcome was death or the initiation of kidney replacement therapy. The secondary outcome was death or hospitalization due to infection. Infectious diseases such as sepsis, pneumonia, urinary tract infections, cellulitis, cytomegalovirus infection, colitis, or hepatitis were defined as infections. Hazard ratios were expressed using group C as a reference. RESULTS: Of 1,642 patients, the incidence of the primary outcome occurred in 62/460 individuals in the PSL group, 81/635 individuals in the PSL + IS group, and 47/547 individuals in the C group. The Kaplan-Meier survival curve showed no significant differences (P = 0.088). The incidence of secondary outcomes occurred in 80/460 individuals, 102/635 individuals, and 37/547 individuals in the PSL, PSL + IS, and C groups, respectively. The incidence of secondary outcomes was significantly higher in the PSL group (hazard ratio [HR] 2.43 [95% confidence interval [CI] 1.64-3.62, P < 0.01]) and PSL + IS group (HR 2.23 [95% CI 1.51-3.30, P < 0.01]). CONCLUSIONS: The outcome of membranous nephropathy was not completely satisfactory. Patients who use steroids and immunosuppressive agents have a high incidence of infection and may require close monitoring during the course of treatment.High-efficacy treatment with a low incidence of infections is desirable. The significance of this study lies in the fact that the impressions of membranous nephropathy, which have been recognized as tacit knowledge, were quantified using a clinical database.

Membranous nephropathy in the UK Biobank.

BACKGROUND: Despite MN being one of the most common causes of nephrotic syndrome worldwide, its biological and environmental determinants are poorly understood in large-part due to it being a rare disease. Making use of the UK Biobank, a unique resource holding a clinical dataset and stored DNA, serum and urine for ~500,000 participants, this study aims to address this gap in understanding. METHODS: The primary outcome was putative MN as defined by ICD-10 codes occurring in the UK Biobank. Univariate relative risk regression modelling was used to assess the associations between the incidence of MN and related phenotypes with sociodemographic, environmental exposures, and previously described increased-risk SNPs. RESULTS: 502,507 patients were included in the study of whom 100 were found to have a putative diagnosis of MN; 36 at baseline and 64 during the follow-up. Prevalence at baseline and last follow-up were 72 and 199 cases/million respectively. At baseline, as expected, the majority of those previously diagnosed with MN had proteinuria, and there was already evidence of proteinuria in patients diagnosed within the first 5 years of follow-up. The highest incidence rate for MN in patients was seen in those homozygous for the high-risk alleles (9.9/100,000 person-years). CONCLUSION: It is feasible to putatively identify patients with MN in the UK Biobank and cases are still accumulating. This study shows the chronicity of disease with proteinuria present years before diagnosis. Genetics plays an important role in disease pathogenesis, with the at-risk group providing a potential population for recall.

Glomerulosclerosis is a prognostic risk factor in patients with membranous nephropathy and non-nephrotic proteinuria.

OBJECTIVE: To explore the predictive value of the proportion of glomerulosclerosis (GS) incidences on the progression of membranous nephropathy with non-nephrotic proteinuria (NNP). METHODS: This study was a single-center, retrospective, cohort study. Patients with biopsy-proven idiopathic membranous nephropathy were divided into three groups based on the proportion of glomerular sclerosis, and their demographic, clinical, and pathological data were compared. The proportions of primary and secondary endpoints were recorded, and the relationship between GS and primary outcomes (progression to nephrotic syndrome, complete remission, and persistent NNP) and the renal composite endpoint was analyzed. RESULTS: A total of 112 patients were divided into three groups according to the proportions of glomerulosclerosis. The median follow-up time was 26.5 (13-51) months. There were significant differences in blood pressure (p < 0.01), renal interstitial lesions (p < 0.0001), and primary endpoints (p = 0.005). The survival analysis showed that prognosis was significantly worse in patients with a high proportion of GS than in those patients with a middle and low proportion of GS (p < 0.001). The Cox multivariate analysis showed that after adjusting for age, sex, BP, 24-h urinary protein, serum creatinine, treatment scheme, and pathological factors, the risk of renal composite outcome in the low proportion group was 0.076 times higher than that in the high proportion group (p = 0.009, HR = 0.076, 95% CI: 0.011-0.532). CONCLUSION: A high level of glomerulosclerosis was an independent risk factor for the prognosis of patients with membranous nephropathy with non-nephrotic proteinuria.

Clinical features of anemia in membranous nephropathy patients: a Chinese cohort study.

BACKGROUND: Anemia is a common complication in patients with progressive chronic kidney disease. This cohort study evaluated the prevalence, clinical features and prognosis of membranous nephropathy (MN) with anemia. METHODS: We retrospectively analyzed a cohort of MN patients diagnosed using renal biopsy between February 2012 and February 2018. The clinical and pathological characteristics at baseline were recorded, and the outcomes (hemoglobin, proteinuria and renal function) during follow-ups were also evaluated. Univariate and multivariate logistic regression analyses were performed to identify the independent risk factors for anemia in MN patients. The MN patients were divided according to the therapeutic effect they experienced as follows: without-anemia, completely corrected anemia, standard anemia treatment and nonstandard anemia treatment groups. We compared the rate of complete remission of MN and renal end-point events among the four groups. RESULTS: The median age of 483 patients was 42.43 (26.59, 50.20) years at the time of MN diagnosis. The prevalence of anemia at baseline was 23.81%, and the cumulative prevalence was 50.72%. There were 133 cases of mild anemia, 103 cases of moderate anemia and 9 cases of severe anemia; in addition, there were 228 cases of normocytic anemia and 17 cases of microcytic hypochromic anemia. Multivariate logistic regression indicated that acute renal tubule injury >5% (OR = 1.634, 95% CI 1.034, 2.581; p = 0.035), total protein level (OR = 0.949, 95% CI 0.923, 0.975; p < 0.001), cholesterol level (OR = 0.833, 95% CI 0.749, 0.926, p = 0.001), hypokalemia (OR = 2.612, 95% CI 1.227, 5.560, p = 0.013) and hypophosphatemia (OR = 2.653, 95% CI 1.303, 5.403, p = 0.007) were independent risk factors for anemia in MN patients. The complete remission rate of MN patients without anemia was significantly higher than that of anemia patients who exhibited treatment failure. The incidence of renal endpoint events was different among the four groups. CONCLUSION: The anemia experienced by MN patients is mainly mild and moderate, normocytic anemia. The pathological features of acute renal tubular injury and clinical nutritional status are independent risk factors for anemia. There were differences in renal prognosis among anemia patients with different treatment outcomes.

Caracterización de enfermedades glomerulares: análisis de 22 años de biopsias renales / Frequency of glomerular diseases in an analysis of 550 kidney biopsies

BACKGROUND: The frequency of glomerular diseases is dynamic and varies according to geographic area. AIM: To evaluate the frequency of primary and secondary glomerulopathies, their demographic profile and main clinical characteristics. MATERIAL AND METHODS: Renal biopsies from native kidneys performed between 1999 and 2020 were retrospectively reviewed. Demographic characteristics, clinical presentation, most relevant laboratory tests, frequency of primary and secondary glomerulopathies were analyzed. RESULTS: We analyzed 550 kidney biopsies from patients with a median age of 48 years (64% females). Nephrotic syndrome was the main indication for renal biopsy. Primary and secondary glomerulopathies occurred with similar frequency. Within the primary glomerulopathies, membranous nephropathy (34.1%) was the most common, followed by IgA nephropathy (31.1%) and focal segmental glomerulosclerosis (14.1%). Among the secondary glomerulopathies, lupus nephropathy was the most common (41.7%), followed by pauciimmune glomerulonephritis (27.1%) and diabetic nephropathy (6.4%). When comparing the results with other regions, significant differences were observed with reported frequencies in United States, Europe, Asia and the rest of Latin America. CONCLUSIONS: The most common primary glomerulopathies were membranous nephropathy and IgA nephropathy. Among the secondary glomerulopathies lupus nephropathy and pauci-immune glomerulonephritis were the most common. Compared to international registries, we observed a high proportion of membranous nephropathy and pauci-immune glomerulonephritis.

Spectrum and Distribution of Biopsy-proven Kidney Diseases: A 12-year Survey of a Single Center in Iran.

Data about the prevalence of biopsy-proven kidney diseases in Iran are rare, and none of the previous studies used electron microscopy for diagnosis. This study aimed to analyze the prevalence of biopsy-proven kidney diseases in Iran's primary referral center. To the best of our knowledge, this is the most extensive study carried out in Iran. Reports of kidney biopsy samples from patients referred to our center in 2007-2018 were reviewed for demographic data, clinical presentation, and final diagnosis. Statistical analyses were performed. Among the 3455 samples received, 2975 were analyzed. Nephrotic syndrome (39%) was the most common cause of biopsy, followed by subnephrotic proteinuria (18%), hematuria in association with proteinuria (15%), renal failure (9%), isolated hematuria (6%), and lupus nephritis (LN) (4%). The most common diagnoses were membranous glomerulonephritis (17.9%), focal segmental glomerulosclerosis (FSGS) (15.9%), LN (13.7%), minimal histopathological findings (unsampled FSGS vs. minimal change disease, 12.1%), Immunoglobin A nephropathy (IgAN) (6.5%) and Alport syndrome (6.1%). NS and proteinuria were the most common indications for a kidney biopsy. IgAN and LN were the most common causes of primary and secondary glomerulonephritis, presenting with hematuria and proteinuria, respectively. Although membranous glomerulonephritis was the most common disease, it has been replaced by FSGS in recent years.

New-Onset and Relapsed Membranous Nephropathy post SARS-CoV-2 and COVID-19 Vaccination.

Since the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak and COVID-19 vaccination, new-onset and relapsed clinical cases of membranous nephropathy (MN) have been reported. However, their clinical characteristics and pathogenesis remained unclear. In this article, we collected five cases of MN associated with SARS-CoV-2 infection and 37 related to COVID-19 vaccination. Of these five cases, four (4/5, 80%) had acute kidney injury (AKI) at disease onset. Phospholipase A2 receptor (PLA2R) in kidney tissue was negative in three (3/5, 60%) patients, and no deposition of virus particles was measured among all patients. Conventional immunosuppressive drugs could induce disease remission. The underlying pathogenesis included the subepithelial deposition of viral antigens and aberrant immune response. New-onset and relapsed MN after COVID-19 vaccination generally occurred within two weeks after the second dose of vaccine. Almost 27% of patients (10/37) suffered from AKI. In total, 11 of 14 cases showed positive for PLA2R, and 20 of 26 (76.9%) presented with an elevated serum phospholipase A2 receptor antibody (PLA2R-Ab), in which 8 cases exceeded 50 RU/mL. Conventional immunosuppressive medications combined with rituximab were found more beneficial to disease remission for relapsed patients. In contrast, new-onset patients responded to conservative treatment. Overall, most patients (24/37, 64.9%) had a favorable prognosis. Cross immunity and enhanced immune response might contribute to explaining the mechanisms of MN post COVID-19 vaccination.

Diagnosis and Course of Membranous Nephropathy in Adults: Comparison by Age Group.

INTRODUCTION: There have been few studies comparing younger and older adults with membranous nephropathy. The objective of this study was to compare younger and older patients with membranous nephropathy, in terms of the clinical, etiological, remission, and survival data. METHOD: This was a retrospective study of patients with membranous nephropathy who underwent renal biopsy between 2009 and 2017. RESULTS: We included 214 patients with membranous nephropathy. At diagnosis, 169 (79%) of those patients were <60 years of age and 45 (21%) were ≥60 years of age. There was a predominance of males in both groups. The degree of proteinuria and the prevalence of hematuria did not differ significantly between the groups. However, the median serum creatinine level was higher in the ≥60-year group as was the prevalence of hypertension. Of the patients evaluated, 36 (16.8%) had secondary membranous nephropathy. Although the proportions of infectious and autoimmune causes were comparable between the two groups, neoplastic etiologies were more common in the ≥60-year group. A total of 86 in the <60-year group and 25 in the ≥60-year group were followed long term, and partial or complete remission was achieved in 68.5% and 68.0% of the younger and older patients, respectively. However, whom progressed to requiring dialysis eight (9.3%) were in the <60-year group patients and eight (32.0%) of the ≥60-year group patients (p = 0.0045). CONCLUSION: Despite having worse renal function at diagnosis, older patients with membranous nephropathy appear to have remission rates comparable to those of younger patients with the disease, which demonstrates the benefits of seeking diagnosis and treatment.

Toxic Occupational Exposures and Membranous Nephropathy.

BACKGROUND AND OBJECTIVES: Membranous nephropathy is a rare autoimmune kidney disease whose increasing prevalence in industrialized countries pleads for the involvement of an environmental factor in the development of the disease. In addition, the predominance of men in membranous nephropathy, classically attributed to biologic or genetic differences between men and women, could also be due to different occupational exposures. To support this hypothesis, we sought to describe the toxic occupational exposures of patients with membranous nephropathy. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In this observational epidemiologic study, we compared the occupations and toxic occupational exposures of 100 patients with membranous nephropathy with those of the general population, consisting of two cohorts of 26,734,000 and 26,500 French workers. We then compared the characteristics of patients exposed to an occupational toxic substance with those of unexposed patients. RESULTS: Patients with membranous nephropathy worked more frequently in the construction sector than the general population (33% versus 7%, P<0.001). This difference remained significant by age and sex. They were also more frequently exposed to toxic substances, such as asbestos (16% versus 5%, P<0.001), lead (9% versus 1%, P<0.001), or organic solvents (37% versus 15%, P<0.001), than the general population. The predominance of men in the subgroup of patients occupationally exposed to toxic substances was not observed in unexposed individuals (organic solvents: 80% men versus 41%, P<0.001; asbestos: 90% men versus 55%, P=0.004). In addition, patients with phospholipase A2 receptor 1 (PLA2R1) epitope spreading were more frequently exposed to asbestos and organic solvents than patients without epitope spreading (32% versus 7%, P=0.02 and 74% versus 43%, P=0.02, respectively), with a dose-dependent effect. CONCLUSIONS: Patients with membranous nephropathy were more frequently exposed to certain occupational toxic substances, such as asbestos and organic solvents, than the general population. This occupational exposure was more frequent in men and in patients with PLA2R1 epitope spreading. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: Immunopathological Analysis in a French National Cohort of Membranous Nephropathy (IHMN), NCT04326218. PODCAST: This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2022_10_25_CJN02930322.mp3.

Epidemiological characteristics and pathological changes of primary glomerular diseases.

OBJECTIVE: By analyzing the pathological characteristics and clinical data of renal biopsy in our hospital in the past 20 years, to further understand the epidemic characteristics and pathological changes of primary glomerular disease, and to provide regional data for the big data of kidney disease in my country. METHODS: A retrospective analysis of 9448 patients with primary glomerular disease who were hospitalized in our hospital from January 1, 2000 to December 31, 2019, aged 18 years or older, and undergoing renal biopsy. Divided every 5 years into a group, a total of 4 groups (first group 2000.1.1-2004.12.31, second groups 2005.1.1-2009.12.31; third groups 2010.1.1-2014.12.31, fourth groups 2015.1.1-2019.12.31). RESULTS: ① There were more males than females, and male: female vs 1.53:1. The proportion of men in the past five years has increased compared with the previous 15 years. ② Mostly middle-aged, with a median age of 41.39 years old. The age is increasing over time. There are differences between the four groups, P <0.001; ③ The most common clinical manifestations are nephrotic syndrome, followed by chronic glomerulonephritis. Occult glomerulonephritis, the proportion of patients with nephrotic syndrome increases over time, first to fourth group (40.08%< 42.64% < 47.08%< 53.69%); ④ The most common pathology type from 2000 to 2009 was mesangial proliferative glomerulonephritis. IgA nephropathy was the most common type from 2010 to 2014, but the proportion of membranous nephropathy increased year by year, and it became the most common pathological type from 2015 to 2019; ⑤ The clinical and pathological manifestations of different genders are different, but there is no statistical difference. CONCLUSION: In the past 20 years, the primary glomerular disease is mainly middle-aged. There are more men than women. The most common type of clinical manifestation is nephrotic syndrome. The pathological type is mesangial proliferative glomerulonephritis. Over time, the average age is increasing, and the proportion of patients with renal syndrome is increasing. IgA nephropathy is the most common pathological type from 2010 to 2014, and membranous nephropathy has become the main pathological type in the past 5 years.

Changes in the spectrum of kidney diseases: a survey of 2803 patients from 2010 to 2018 at a single center in southeastern China.

Primary glomerular disease was the leading cause of chronic kidney disease (CKD) in China; however, changes in the economy and environment introduce variations in the spectrum of kidney diseases. This study aimed to analyze renal biopsy data to inform disease prevention and public health interventions. In this retrospective cohort study, data from 2,803 consecutive renal biopsies conducted at our center between January 2010 and December 2018 were analyzed. The sample was disaggregated by age and the date of biopsy to facilitate analysis. Primary glomerulonephritis (PGN) is the most frequent (81.84%) finding, followed by secondary glomerulonephritis (SGN; 15.38%), tubulointerstitial nephritis (15.38%), and others (1.57%). IgA nephropathy (IgAN), idiopathic membranous nephropathy (iMN), and minimal change disease were the primary causes of PGN. Among PGN cases, the incidence of iMN arose, especially among those aged ≥ 60 years old, during the observation period. Contrary to the case of iMN, the proportion of IgAN in PGN trended downward, continuously, and at length. Moreover, IgAN mainly affected those aged 25-44 years old and less so those aged ≥ 60 years old. Lupus nephritis, Henoch-Schönlein purpura nephritis, and diabetic nephropathy (DN) were key causes of SGN. A ratio reversal between infectious disease and chronic disease dramatically changed SGN patterns. In the past year, the incidence of hepatitis B-related nephritis has constantly declined; however, the proportion of DN among SGN had steadily increased. The incidence of iMN significantly increased during these years. Among SGN cases, the proportion of DN has increased.

Disease spectrum of 9 310 cases of renal biopsy pathological diagnosis from a single center in China. / 中国单中心9 310ä¾‹è‚¾æ´»æ£€ç— ç†è¯Šæ–­ç–¾ç— è°±.

OBJECTIVES: The pathological types of renal diseases have changed in the past decade, but it lacks large sample analysis in Hunan Province. This study aims to retrospectively analyze the composition characteristics of pathological spectrum of kidney disease in Hunan Province in recent 10 years, compare the changes of pathological types of kidney disease. METHODS: We collected a total of 9 310 kidney biopsy cases from 2011 to 2020 registered in the kidney biopsy system of the Nephrology Institute of the Second Xiangya Hospital of Central South University. Patients were assigned into a 14-24 years old group, a 25-44 years old group, a 45-59 years old group, and a ≥60 years old group, and divided into 2 time periods, namely 2011-2015 and 2016-2020. Pathological types of renal disease were divided into primary glomerulonephritis (PGN), secondary glomerulonephritis (SGN), tubulo-interstitial nephritis (TIN), hereditary kidney disease, and other pathological types. RESULTS: PGN accounted for 66.93% cases. Among PGN, IgA nephropathy (IgAN) (42.83%), membranous nephropathy (MN) (19.16%), minimal change glomerulopathy (12.46%), and focal segmental glomerulosclerosis (FSGS) (14.97%) were the 4 most common pathological types. Compared with the group in the period of 2011-2015, IgAN (46.74% vs 37.33%) and MN (21.26% vs 16.18%) were increased significantly in years 2016-2020 (both P<0.001). SGN accounted for 24.49% cases, of which lupus nephritis (LN) (26.91%), hypertensive nephropathy (HT) (14.47%), diabetic nephropathy (DN) (12.25%), and henoch-schonlein purpuric nephritis (HSPN) (13.44%) were the 4 most common pathological types. LN (32.53%), HSPN (12.97%), hepatitis B virus associated nephritis (HBVN) (10.98%), HT (9.48%) were the most common SGN in the period of 2011-2015. In the period of 2016-2020, the top 4 pathological types of SGN were LN (23.21%), HT (17.75%), DN (15.84%), and HSPN (13.74%). LN was the most common type in young adults ≤44 years old. HT, DN, and monoclonal immunoglobulin associated renal disease (including amyloidosis nephropathy) became the main pathological types of SGN in middle-aged and elderly patients. CONCLUSIONS: IgAN remains the primary pathological type of kidney disease in China in the recent years. The patients with the age of 25-44 years old have the largest proportion of IgAN. With increases in age, the proportion of IgAN gradually decreases. MN increases to different degrees at various ages, while cases of HT, DN, and monoclonal immunoglobulin-related renal damage have increased. This single-center renal pathology spectrum can provide clinical evidence for diagnosis, prevention and epidemiological study.

Prevalence of neural epidermal growth factor-like 1- and exostosin 1/exostosin 2-associated membranous nephropathy: a single-center retrospective study in Japan.

Membranous nephropathy (MN) is the leading cause of nephrotic syndrome in adults. We previously reported that the prevalence of phospholipase A2 receptor (PLA2R)- and thrombospondin type 1 domain containing 7A (THSD7A)-associated MN patients in Japan is 52.7% and 9.1%, respectively. In addition to PLA2R and THSD7A, we assessed the presence of newly discovered target antigens, neural epidermal growth factor-like 1 (NELL-1), semaphorin 3B (SEMA3B), and exostosin 1/exostosin 2 (Ext1/Ext2), in renal specimens from patients with primary and secondary MN by immunohistochemistry. We found enhanced glomerular staining of PLA2R, THSD7A, NELL-1, and Ext1/Ext2 in 53.6%, 8.7%, 1.5%, and 13.0% of the renal samples, respectively, in patients with primary MN. None of the patient specimens showed enhanced staining of SEMA3B. Enhanced glomerular staining of PLA2R, NELL-1, and Ext1/Ext2 was detected in 5.7%, 8.6%, and 22.9% of the patients with secondary MN, respectively. Based on our findings, we recommend the assessment of PLA2R, THSD7A and NELL-1 in addition to clinical information and IgG4 staining to differentiate between primary and secondary MN. This would aid in distinguishing secondary MN patients from primary MN patients who coincidentally have some secondary characteristics.

Epidemiology and Outcomes of Glomerular Diseases in Low- and Middle-Income Countries.

Glomerular diseases account for a significant proportion of chronic kidney disease in low-income and middle-income countries (LMICs). The epidemiology of glomerulonephritis is characterized inadequately in LMICs, largely owing to unavailable nephropathology services or uncertainty of the safety of the kidney biopsy procedure. In contrast to high-income countries where IgA nephropathy is the dominant primary glomerular disease, focal segmental glomerulosclerosis is common in large populations across Latin America, Africa, Middle East, and South East Asia, while IgA nephropathy is common in Chinese populations. Despite having a high prevalence of known genetic and viral risk factors that trigger focal segmental glomerulosclerosis, membranoproliferative glomerulonephritis also is common in adults and children in some African countries. Treatment of glomerular diseases in adults and children in LMICs largely is dependent on corticosteroids in combination with other immunosuppressive therapy, which often is cyclophosphamide because of its ready availability and low cost of treatment, despite significant adverse effects. Partial and/or complete remission status reported from studies of glomerular disease subtypes vary across LMIC regions, with high rates of kidney failure, mortality, and disease, and treatment complications often reported. Improving the availability of nephropathology services and ensuring availability of specific therapies are key measures to improving glomerular disease outcomes in LMICs.