Incidence and outcomes of kidney replacement therapy for end-stage kidney disease due to primary glomerular disease in Europe: findings from the ERA Registry

BACKGROUND

Primary glomerular disease (PGD) is a major cause of end-stage kidney disease (ESKD) leading to kidney replacement therapy (KRT). We aimed to describe incidence (trends) in individuals starting KRT for ESKD due to PGD and to examine their survival and causes of death.

METHODS

We used data from the European Renal Association (ERA) Registry on 69 854 patients who started KRT for ESKD due to PGD between 2000 and 2019. ERA primary renal disease codes were used to define six PGD subgroups. We examined age and sex standardized incidence, trend of the incidence and survival.

RESULTS

The standardized incidence of KRT for ESKD due to PGD was 16.6 per million population (pmp), ranging from 8.6 pmp in Serbia to 20.0 pmp in France. Immunoglobulin A nephropathy (IgAN) and focal segmental glomerulosclerosis (FSGS) had the highest incidences, of 4.6 pmp and 2.6 pmp, respectively. Histologically non-examined PGDs represented over 50% of cases in Serbia, Bosnia and Herzegovina, and Romania and were also common in Greece, Estonia, Belgium and Sweden. The incidence declined from 18.6 pmp in 2000 to 14.5 pmp in 2013, after which it stabilized. All PGD subgroups had 5-year survival probabilities above 50%, with crescentic glomerulonephritis having the highest risk of death [adjusted hazard ratio 1.8 (95% confidence interval 1.6-1.9)] compared with IgAN. Cardiovascular disease was the most common cause of death (33.9%).

CONCLUSION

The incidence of KRT for ESKD due to PGD showed large differences between countries and was highest and increasing for IgAN and FSGS. Lack of kidney biopsy facilities in some countries may have affected accurate assignment of the cause of ESKD. The recognition of the incidence and outcomes of KRT among different PGD subgroups may contribute to a more individualized patient care approach.

Clinicopathological Characteristics and Disease Chronicity in Glomerular Diseases: A Decade-Long Study at Romania's Largest Kidney Biopsy Reference Center

Glomerular diseases (GDs), significant causes of end-stage kidney disease, are better understood through epidemiological studies based on kidney biopsies (KBs), which provide important insights into their prevalence and characteristics. This study aims to analyze the clinicopathological features of GDs diagnosed from 2008 to 2017 at Romania's largest reference center. In this decade-long study, 1254 adult patients diagnosed with GDs were included. The local previously validated renal histopathological prognostic score was calculated for each KB using four histopathologic lesions: global glomerulosclerosis, tubular atrophy, interstitial fibrosis and fibrocellular/fibrous crescents. The mean patient age was 50 years, with a male predominance (57%). The primary referral reasons were nephrotic syndrome (46%), nephritic syndrome (37%), chronic kidney disease (12%), asymptomatic urinary abnormalities (4%), and acute kidney injury (1%). Immunoglobulin A nephropathy (IgAN) was the most frequently diagnosed GD (20%), aligning with frequencies reported in European registries. Diabetic glomerular nephropathy was the most common secondary GD (10%). It also presented the highest median renal histopathological prognostic score (2), indicating a poorer prognosis. Lower eGFR and higher proteinuria were independently associated with higher scores. This decade-long study highlights IgAN as the most frequent GD diagnosed by KB. Diabetic glomerular nephropathy was identified as the most common secondary GD. The renal histopathological prognostic score, notably high in diabetic glomerular nephropathy patients, was correlated with lower eGFR and higher proteinuria, underlining its clinical relevance.

Twenty-four-Year Trends in Incidence and Mortality of Nephrotic Syndrome: A Population-Based Cohort Study

BACKGROUND

With the increasing prevalence of risk factors for nephrotic syndrome, updated epidemiologic data on the syndrome are needed. We examined its age- and sex-specific incidence, histopathology, and mortality over 24 years.

METHODS

This nationwide cohort study included all adults with first-time-recorded nephrotic syndrome in Denmark during 1995-2018 using the Danish National Patient Registry. We obtained data on age, sex, hospital-diagnosed comorbidities, and histopathologic findings. We computed overall, and age- and sex-specific, incidence rates of nephrotic syndrome, 1- and 5-year mortality by calendar period, and 1-year hazard ratios (HRs) of death using Cox models.

RESULTS

We identified 3,970 adults with first-time nephrotic syndrome diagnosis. Incidence was highest in men and increased with age to 11.77 per 100,000 person-years (95% confidence interval [CI]: 10.21-13.32) in men aged 80+ years, and 6.56 per 100,000 person-years (95% CI: 5.71-7.41) in women aged 80+ years. Incidence of nephrotic syndrome increased from 3.35 per 100,000 person-years (95% CI: 3.12-3.58) in 1995-2000 to 4.30 per 100,000 person-years (95% CI: 4.05-4.54) in 2013-2018. Over time, 1-year mortality of nephrotic syndrome was stable at 13%-16%, but HR of death was 0.54 (95% CI: 0.42-0.69), adjusted for age, sex, and comorbidities, in 2013-2018 compared with 1995-2000. Subdistribution of glomerulopathies was stable over time with membranous nephropathy and minimal change disease being the most common.

CONCLUSION

During 1995-2018, the incidence of recorded adult nephrotic syndrome increased slightly, and the adjusted mortality of nephrotic syndrome decreased markedly. Whether these findings reflect changes in epidemiology or awareness and coding of nephrotic syndrome, remains to be clarified.

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.

How useful is kidney biopsy for the management of glomerulopathies in the elderly?

BACKGROUND

The use of kidney biopsy in elderly individuals is still matter of discussion. The purpose of this study is to assess the utility of kidney biopsy for the management of glomerulopathies in an Eastern European cohort, targeting patients older than 65 years.

METHODS

This retrospective study included 875 adults (147 older than 65 years), with biopsy-proven glomerulopathies, followed up for 71.1 (95% CI 68.2-73.9) months. The primary endpoint was chronic renal replacement therapy initiation. Statistical evaluation was performed with IBM SPSS software version 20, Analyse-it, and SAS Studio. The Kaplan-Meier method was used to estimate the time to death and the log-rank test was used for comparisons. The multivariate Cox proportional hazard analysis was used to evaluate the risk of death.

RESULTS

Secondary glomerulopathies were more frequent in patients aged > 65 years (52.4% vs. 41.9%, p = 0.004). Membranous nephropathy and amyloidosis were the most frequent primary and secondary glomerulopathies in this age group. Kidney biopsy complications were low (< 4%) in both age groups. In 42% of the elderly, the result of biopsy guided the immunosuppressive therapy. While the all-cause mortality rate was higher (OR 4.2; 95% CI 2.7-6.7; p < 0.0001) in elderly individuals, the rate of renal replacement therapy initiation was similar (31.3 vs 26%; p = 0.1) in both age groups. In the competitive risk analysis, kidney survival was similar irrespective of age [CIF 0.4 (95% CI 0.26-0.53) vs. 0.34 (95% CI 0.28-0.39), p = 0.08]. However, after adjusting for the confounding factors, younger age was associated with an increased risk of renal replacement therapy (HR = 1.57, p = 0.01), along with secondary glomerulopathies.

CONCLUSION

The diagnosis of an underlying glomerulopathy guided the therapy in almost one-half of the elderly patients who underwent a kidney biopsy, provided important prognostic information and had a low complications rate; kidney biopsy may therefore be considered a safe, reliable procedure in the management of glomerulopathies, even in patients over 65 years of age.

Clinicopathological characteristics and disease chronicity in native kidney biopsies in Flanders

Background

The Flemish Collaborative Glomerulonephritis Group (FCGG) registry provides complete population data on kidney disease epidemiology in the region of Flanders (Belgium), as it captures all native kidney biopsies performed in its population of 6.5 million inhabitants.

Methods

From 2017 until 2019, 2054 adult kidney biopsies were included from 26 nephrology centers (one biopsy per patient). Data on nephrotic and nephritic syndrome were available in 1992 and 2026 biopsies, respectively. In a subgroup of 898 biopsies containing ≥10 glomeruli from 2018 to 2019, disease chronicity was graded using the Mayo Clinic Chronicity Score (MCCS). The association between clinical variables and MCCS was determined using simple and multiple linear regression models.

Results

Nephrotic syndrome (present in 378 patients, 19.0%) was most frequently caused by minimal change disease in younger patients (18-44 years), membranous nephropathy in older patients (45-74 years) and amyloidosis in the elderly (>75 years). Nephritic syndrome (present in 421 patients, 20.8%) was most frequently caused by immunoglobulin A nephropathy (IgAN) in younger patients (18-64 years) and ANCA-associated vasculitis (AAV) in older patients (>64 years). AAV and IgAN were the most frequent underlying diagnoses in biopsies in which crescents were identified. In multivariable analysis, acute and chronic kidney disease and diagnoses of diabetic kidney disease, nephrosclerosis and hyperoxaluria/hypercalcemic nephropathy were associated with the highest MCCS increases.

Conclusions

The FCGG registry validates data from previous Western European registries and provides a snapshot of disease chronicity in the whole biopsied Flemish population.

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.

Renal biopsy reports in nephritic syndrome: Update

BACKGROUND

Nephritic syndrome (NiS) is a major indicator of serious renal diseases necessitating kidney biopsies for histopathological evaluations, but due to the lack of comprehensive reviews in the literature, the current understanding of the syndrome and its significance is limited.

AIM

To collect all the evidence retrievable from the literature on the diagnoses made on the renal biopsies performed for NiS as the indication to the procedure.

METHODS

A literature search was conducted to find studies reporting final diagnoses on renal biopsies in NiS patients. Data were pooled and analyzed with stratifications on age and regions. Meta-analyzes were performed using Stata v.9.

RESULTS

Overall, 26414 NiS patients from the total number of 96738 kidney biopsy diagnoses reported by 47 studies from 23 countries from all continents (except sub-Saharan Africa) were found and analyzed. NiS was the indication for renal biopsy in 21% of the patient populations across the reviewed studies. Immunoglobulin A (IgA) nephropathy was the single most frequent diagnosis in these patients (approximately 38%) followed by lupus nephritis (approximately 8%) and Henoch Schönlein purpura (approximately 7%). IgA nephropathy was the most frequent diagnosis reported for the NiS patients from the East Asia, comprising half of all the cases, and least prevalent in South Asia. Considering the age subgroups, adult (vs pediatric or elderly) patients were by far the most likely age group to be diagnosed with the IgA nephropathy. A myriad of such regional and age disparities have been found and reported.

CONCLUSION

As the indication for renal biopsy, NiS represents a very distinctive epidemiology of final renal disease diagnoses compared to the other major syndromes.

Epidemiology of native kidney disease in Flanders: results from the FCGG kidney biopsy registry

Background

The Flemish Collaborative Glomerulonephritis Group (FCGG) registry is the first population-based native kidney biopsy registry in Flanders, Belgium. In this first analysis, we report on patient demographics, frequency distribution and incidence rate of biopsied kidney disease in adults in Flanders.

Methods

From January 2017 to December 2019, a total of 2054 adult first native kidney biopsies were included. A ‘double diagnostic coding’ strategy was used, in which every biopsy sample received a histopathological and final clinical diagnosis. Frequency distribution and incidence rate of both diagnoses were reported and compared with other European registries.

Results

The median age at biopsy was 61.1 years (interquartile range, 46.1–71.7); male patients were more prevalent (62.1%) and biopsy incidence rate was 129.3 per million persons per year. Immunoglobulin A nephropathy was the most frequently diagnosed kidney disease (355 biopsies, 17.3% of total) with a similar frequency as in previously published European registries. The frequency of tubulointerstitial nephritis (220 biopsies, 10.7%) and diabetic kidney disease (154 biopsies, 7.5%) was remarkably higher, which may be attributed to changes in disease incidence as well as biopsy practices. Discordances between histopathological and final clinical diagnoses were noted and indicate areas for improvement in diagnostic coding systems.

Conclusions

The FCGG registry, with its ‘double diagnostic coding’ strategy, provides useful population-based epidemiological data on a large Western European population and allows subgroup selection for future research.

Kidney biopsy-based epidemiologic analysis shows growing biopsy rate among the elderly

Systematic registration and examination of biopsy-related data in Central and Eastern Europe are scarce, while the health condition of the population is worse compared to other more developed countries. We aim to create a database and analyze the distribution and temporal variation of the renal biopsy diagnoses in Hungary, including the effect of the recent coronavirus pandemic. The diagnoses were standardized according to the recommendation of the European Renal Association. Native biopsy samples processed between January 1, 2006, and December 31, 2020, were analyzed. During the 15 years, 2140 native kidney biopsies were performed. The number of samples increased from 24.5 to 57.9 per million person-years and the median age from 37 to 51 years (p < 0.0001). The predominance of glomerular diseases was stable. The most frequent glomerulopathy was IgA nephropathy (21.5%), followed by focal segmental glomerulosclerosis (17.7%), and membranous nephropathy (15.7%). Trends showed the rise of ANCA-associated vasculitis. During the coronavirus pandemic, there was a decrease in the number of kidney biopsies and the proportion of membranous nephropathies. The diagnostic trends in our database showed increasing biopsy rates among the elderly and the growing frequencies of age-related diseases, which emphasizes the importance of altering medical focus according to demographic changes in this area.

Chinese medicinal herbs for idiopathic membranous nephropathy in adults with nephrotic syndrome: A systematic review of effectiveness and safety

ABSTRACT

To assess the benefits and harms of Chinese medicinal herbs formulae for the treatment of idiopathic membranous nephropathy in adult patients with primary nephrotic syndrome.Only randomized controlled trials were included. We searched the Cochrane Central Register of Controlled Trials database, PubMed, EMBASE, Chinese National Knowledge Internet, Chinese Biomedicine Database, and VIP. All studies were analyzed using the criteria of the Cochrane Handbook and were assessed in terms of quality and the risk of bias. Review Manager ver. 5.3.5 software was used for the data analysis, and GRADE profiler software was employed to evaluate quality.Two studies were included (n = 126 Chinese participants). We found that compared with against conventional treatment, one Chinese medicinal herbs formula plus conventional treatment reduced 24-hours urinary total protein (mean differences -3.16 g/24 h, 95% confidence intervals -4.03 to -2.29), and two Chinese medicinal herbs formulae increased serum albumin levels (mean differences 3.18 g/L, 95% confidence intervals 1.12 to 5.52; I2 = 0%).Chinese medicinal herbs formulae may reduce 24-hours urinary total protein and increase serum levels of albumin. However, larger and multicenter studies with high methodological quality are still needed.

Epidemiology of biopsy-proven glomerulonephritis in the past 25 years in the North-Eastern area of Romania

PURPOSE

The aim of this retrospective study was: to analyze the epidemiological patterns of the kidney disease based on clinical and histological features in a single-center in the N-E region of Romania, between 2011 and 2019 and to compare the biopsy results with the others periods, as well as the results from other countries.

METHODS

We studied 442 renal biopsies. The indications for renal biopsy were represented by the clinical features: nephrotic syndrome, nephritic syndrome, asymptomatic urinary abnormalities, acute kidney injury, and chronic kidney disease of unknown etiology.

RESULTS

During the past 8 years, the annual incidence of renal biopsies was constant, albeit this incidence remained lower than in other countries. Nephrotic syndrome was the most common indication for renal biopsy (47.6%). Primary glomerulonephritis (GN) was the most common diagnosis in each of the three periods, followed by secondary GN. Vascular nephropathy and TIN were constant as a proportion from the overall biopsies in each of the three periods. The membranoproliferative GN (24.4%) and membranous nephropathy (MN) (21.9%) were the most prevalent primary GN, while lupus nephritis (LN) was the most common secondary glomerular disease in young female patients (7.5%). Compared to 1994-2004 period, we observed a significant decrease of incidence of focal segmental glomerulosclerosis (FSGS) and mesangial proliferative GN, and a significant increases in the frequency of MN.

CONCLUSION

The results of this study show that the GN distribution model was constant in N-E Romania and became similar to that observed in many countries with high socio-economic status.

Pattern of kidney diseases in Northern India: an overview through histopathological findings in biopsy-proven cases

Background

A kidney biopsy is being increasingly performed for the diagnosis of renal diseases. It is a reasonably safe procedure that helps not only to reach the correct diagnosis based on histopathological findings but also helps in predicting the clinical course and outcome. The pattern of kidney diseases varies not only in far apart geographical regions but also in the same country. This study was done to evaluate the demographic pattern and spectrum of kidney diseases in renal biopsy-proven cases in an admitted patient of a tertiary care hospital of northern India.

Results

The mean age of patients was 41.3 years ± 18.39 years, and the male-to-female ratio was 1.7:1. The most common indication for biopsy in this study was nephrotic syndrome (40.5%). The primary glomerular disease was most common, accounting for 57.5% of cases. Membranous nephropathy (MN) was the most frequently observed histopathological diagnosis not only in the primary glomerular disease category (22.9%) but of all cases (13.2%) as well. Among secondary cases, diabetic nephropathy was most frequent, constituting 43.4% cases. Interstitial and vascular diseases accounted for 18.8% and 1.8% of total cases, respectively. While minimal change disease (MCD) was the most common diagnosis in < 18-year age group, membranous nephropathy was most common above this age. Regarding the gender factor, membranoproliferative glomerulonephritis had an equal distribution among both genders, while MCD had a female preponderance.

Conclusions

Primary glomerular disease is the predominant kidney disease in northern India with MN being the most common histopathological diagnosis. The spectrum of kidney diseases varied with patient’s age and gender.

Glomerular disease frequencies by race, sex and region: results from the International Kidney Biopsy Survey

Background

Large-scale studies comparing glomerular disease frequencies across continents are lacking.

Methods

We surveyed 29 nephropathology laboratories in four continents using a standardized data collection form. We obtained recent consecutive kidney biopsy diagnosis frequencies at each center and summary demographics for each diagnosis. This report focuses on glomerular disease frequencies by region and race/ethnicity.

Results

Among 42 603 glomerular disease diagnoses reported (median age 47 years, 52% male, 57% white), from a total of 60 340 diagnoses, glomerular disease subtype frequencies differed considerably by continent. Diabetic glomerulosclerosis (GS; 19.1%) and focal segmental glomerulosclerosis (FSGS; 19.1%) predominated in North America; lupus nephritis (38.1%) and FSGS (15.8%) predominated in Latin America; IgA nephropathy (IgAN; 22.1%) and FSGS (14.9%) predominated in Europe; and IgAN (39.5%) and lupus nephritis (16.8%) predominated in Asia. After stratifying by race, diabetic GS (17.4% versus 4.3%, P < 0.001) and FSGS (17.3% versus 11.8%, P < 0.001) were more, and lupus nephritis less (15.8% versus 45.6%, P < 0.001), frequent among Latinos in North versus Latin America; FSGS was more (13.1% versus 7.1%, P < 0.001), and IgAN less (27.4% versus 40.5%, P < 0.001), frequent among Asians in North America versus Asia; and FSGS (18.9% versus 13.5%, P < 0.001) and diabetic GS (18.7% versus 6.5%, P < 0.001) were more, and IgAN less (14.4% versus 25.4%, P < 0.001), frequent among whites in North America versus Europe.

Conclusions

We determined that glomerular disease frequencies differed by continent, even among patients of similar race/ethnicity. Regional environmental and lifestyle factors, and local biopsy policies, might influence glomerular disease epidemiology independently of race/ethnicity.

Epidemiology of IgA Nephropathy: A Global Perspective

IgA nephropathy (IgAN), or Berger's disease, is the most common primary glomerular disease worldwide, but varies largely in its geographic distribution. A systematic review of 1,619 publications from the five continental regions of the world was performed to assess the prevalence of IgAN in different worldwide regions and analyze factors responsible for geographic differences. All observational studies that described the prevalence and incidence data on glomerulonephritis were considered. IgAN is more frequent in Asian populations (45 cases per million population/y in Japan) than in Caucasians (31 cases per million population/y in France). These differences are owing to some relevant aspects: (1) systematic mass screening of urine in populations, as occurring in some Asian countries (Hong Kong, Japan, Korea, and Singapore), is not common in Western countries; (2) general practitioners and health care professionals in Western countries underestimate persistent microscopic hematuria and/or mild proteinuria in apparently healthy individuals causing late referral to a nephrologist; and (3) nephrologists adopt different indications for kidney biopsy in individuals with persistent urinary abnormalities. In addition, differences also are owing to the source of data, because the frequency of IgAN observed in a nephrology center with a high incidence of kidney biopsies is higher than in a regional renal biopsy registry that receives data from many centers. In conclusion, greater efforts should be made to diagnose IgAN earlier in individuals who manifest persistent microhematuria and/or mild proteinuria and to introduce less stringent indications for kidney biopsies. This preventive approach, followed by early therapy, may reduce the global burden of end-stage kidney disease caused by IgAN.

Trends of renal diseases in Germany: review of a regional renal biopsy database from 1990 to 2013

Background

Several renal biopsy registries in Europe have shown geographical and temporal variations in the patterns of renal diseases. However, there is a lack of current data on trends of renal disease in Central Europe.

Methods

After exclusion of transplant and re-biopsies, the renal biopsy registry of the German RWTH Aachen University Hospital included data of 1208 biopsies over a period of 24 years (1990–2013). Trends in the biopsy rate and diagnosis of glomerular diseases were analysed.

Results

The average annual biopsy incidence was 6.1 biopsies per 100 000 population. The frequency of kidney biopsies increased significantly over the years (P < 0.001). Primary glomerulonephritis (GN) accounted for nearly two-thirds (58.4%) of all native kidney biopsies, and immunoglobulin A-nephropathy (IgAN) was the leading histological diagnosis (34.7%) followed by necrotizing GN (RPGN) at 18.7%. IgAN increased 2-fold over the study periods (+195%, P < 0.001). Focal segmental glomerulosclerosis accounted for 6.1% of all diagnoses, and its frequency rose to 3.9-fold (+388%, P < 0.001). Lupus nephritis showed a doubling in incidence (P = 0.0499), while acute tubular necrosis decreased to 3.5-fold (P = 0.0008). All other disease entities failed to exhibit linear trends over time. In children, the most common pathologies were IgAN (26.1%) and minimal change disease (21.7%), whereas RPGN (19.4%) dominated in the group of patients >60 years.

Conclusion

IgAN was the most common primary glomerular disease in our centre and its prevalence increased over 24 years.

Changes in the diagnosis of glomerular diseases in east China: a 15-year renal biopsy study

Background: There have been some gradual changes in the distribution of renal biopsy pathological diagnoses during recent years. This study aimed to show changes in renal disease prevalence in China by investigating 10 patients diagnosed at our Kidney Disease Centre during the last 15 years.

Methods and results: All patients aged 15-year-old or older who underwent renal biopsy at the First Affiliated Hospital, Zhejiang University, from 2001 to 2015 were enrolled. There were 5 common types of primary glomerulonephritis: IgA nephropathy (IgA N), membranous nephropathy (MN), mesangial progressive glomerulonephritis (MsPGN), minimal change disease (MCD), and focal segmental glomerulosclerosis (FSGS), which represented 50%, 16.8%, 15.9%, 8.1% and 2.5% of total cases, respectively. IgA nephropathy was the most common type of primary glomerulonephritis (PGN).

Conclusions: Our results mostly showed a new trend that the diagnosis of IgA nephropathy was not increasing and the prevalence of membranous nephropathy had increased, becoming the second most common type of primary glomerulonephritis.

Key POINTS

Distinguished with other domestic studies, IgA nephropathy did not show a trend of continuous growth although it still had about the half proportion of PGN, whereas membranous nephropathy kept rising and became the second common PGN.

Concerning SGN, LN peaked in the younger-age and middle-age groups with a significant female prevalence, DN, BANS and SV had a male predominance peaking in the middle-age and old-age groups.

La ponction biopsie rénale: indications, complications et résultats

La ponction biopsie rénale (PBR) est une technique indispensable au diagnostic des maladies rénales. Ce geste demeure invasif avec diverses complications, essentiellement hémorragiques. L'objectif de notre travail était d'étudier notre pratique de la PBR, mettre le point sur la technique de la biopsie rénale transcutanée, évaluer ses complications, et déterminer les néphropathies diagnostiquées dans notre région. Il s'agit d'une étude rétrospective, menée entre Janvier 2015 et Juin 2017. Nous avons inclus 69 patients du service de Néphrologie du CHU Mohamed VI, Oujda, Maroc ayant bénéficié d'une biopsie de reins natifs. L'âge moyen des patients au moment de la PBR était de 38,16 ±13 ans (12-77 ans), le sexe ratio (H/F) était de 0,86. Le syndrome néphrotique était l'indication la plus fréquente tout âge confondu. Les néphropathies glomérulaires représentaient 81% des maladies rénales, réparties comme suit: la glomérulonéphrite extra-membraneuse retrouvée chez 19% des patients, la hyalinose segmentaire et focale chez 18%, la glomérulonéphrite lupique chez 11%, les glomérulonéphrites chroniques diagnostiquées dans 11% des cas, la glomérulonéphrite membrano-proliférative chez 7%, la glomérulonéphrite extra-capillaire chez 5% à part égale avec l'amylose rénale. Quatre pour cent (4%) des PBR étaient en faveur d'une néphropathie diabétique. Avec un taux estimé à 2% chacune, l'étude histopathologique avait retrouvé la glomérulonéphrite aigue post-infectieuse, la lésion glomérulaire minime, la néphropathie à IgA, les vascularites, les néphropathies tubulo-interstitielles ainsi que la microangiopathie thrombotique. Cinq pour cent (5%) des PBR étaient aglomérulaires. L'hématurie macroscopique était la principale complication observée dans notre série avec une fréquence de 2,8%. La PBR reste le gold standard du diagnostic de la maladie rénale, cependant le diagnostic syndromique permet au clinicien d'identifier la maladie rénale la plus probable et de guider les thérapeutiques urgentes.

Does the pathohistological pattern of renal biopsy change during time?

Biopsy registries are one of the most important sources of accurate epidemiological data and the clinical presentation of renal diseases. A detailed analysis of clinicopathologic correlations over a period of 20 years (1987-2006) was performed earlier by our centre. The aim of this study was to check the current state and to register possible changes in clinicopathologic findings recorded under better socioeconomical circumstances and new management. Records of 665 renal biopsies performed at our institution were prospectively followed from 2007 to 2014. The results were compared with our previously published data. The average annual incidence of renal biopsies increased by 10% and included more elderly patients. Nephrotic syndrome (NS) remained the most common clinical indication for biopsy, while acute kidney injury participated more frequently than in the previous study (p < 0.001). Membranous nephropathy (MN) was still the most common cause of NS. Primary glomerulonephritis (PGN) remained the most prevalent disease, while MN was the most prevalent PGN. In comparison with the earlier period, MN was a more common diagnosis (p = 0.002), while the prevalence of mesangioproliferative non-IgA nephropathy decreased significantly during the time (p = 0.012). LN remained the most frequent secondary glomerulonephritis. The pathohistological pattern of renal biopsy remained largely unchanged during time. However, acute kidney injury was more frequently an indication for biopsy in the current study. The significant increase of biopsied elderly patients is due to the rise in their relative numbers in our population.

Elderly patients with glomerular diseases and IgA nephropathy

As the population ages, greater numbers of elderly patients will present with kidney diseases. Many kidney diseases, such as IgA nephropathy, will require kidney biopsy for diagnostic confirmation, treatment guidance and prognostication. In this paper, we review the current and expected future healthcare landscape with a focus on the ageing population, pros and cons of kidney biopsy in elderly patients, as well as treatment strategies and precautions. We also review the available data on IgA nephropathy in the elderly, including its occurrence rate based on the kidney biopsy, clinicohistopathological features, differentiation with IgA-dominant postinfectious glomerulonephritis, treatment options and outcome prediction. Overall, information on kidney diseases in patients with advanced age, including IgA nephropathy, is limited. Clinical evaluation and management strategies are extrapolated largely from studies in younger adults. Age-specific clinical and translational investigations of kidney diseases are eminently needed.

Regional variations in immunosuppressive therapy in patients with primary nephrotic syndrome: the Japan nephrotic syndrome cohort study

BACKGROUND

The lack of high-quality clinical evidences hindered broad consensus on optimal therapies for primary nephrotic syndromes. The aim of the present study was to compare prevalence of immunosuppressive drug use in patients with primary nephrotic syndrome across 6 regions in Japan.

METHODS

Between 2009 and 2010, 380 patients with primary nephrotic syndrome in 56 hospitals were enrolled in a prospective cohort study [Japan Nephrotic Syndrome Cohort Study (JNSCS)], including 141, 151, and 38 adult patients with minimal change disease (MCD), membranous nephropathy (MN), and focal segmental glomerulosclerosis (FSGS), respectively. Their clinical characteristics were compared with those of patients registered in a large nationwide registry of kidney biopsies [Japan Renal Biopsy Registry (J-RBR)]. The regional prevalence of use of each immunosuppressive drug was assessed among adult MCD, MN, and FSGS patients who underwent immunosuppressive therapy in the JNSCS (n = 139, 127, and 34, respectively). Predictors of its use were identified using multivariable-adjusted logistic regression models.

RESULTS

The clinical characteristics of JNSCS patients were comparable to those of J-RBR patients, suggesting that the JNSCS included the representatives in the J-RBR. The secondary major immunosuppressive drugs were intravenous methylprednisolone [n = 33 (24.6%), 24 (19.7%), and 9 (28.1%) in MCD, MN, and FSGS, respectively] and cyclosporine [n = 25 (18.7%), 62 (50.8%), and 16 (50.0%), respectively]. The region was identified as a significant predictor of use of intravenous methylprednisolone in MCD and MN patients.

CONCLUSION

Use of intravenous methylprednisolone for MCD and MN differed geographically in Japan. Its efficacy should be further evaluated in a well-designed trial.

The Effect of Mycophenolate Mofetil versus Cyclosporine as Combination Therapy with Low Dose Corticosteroids in High-risk Patients with Idiopathic Membranous Nephropathy: a Multicenter Randomized Trial

BACKGROUND

Appropriate immunosuppressive therapy for patients with idiopathic membranous nephropathy (MN) remains controversial. The effect of mycophenolate mofetil (MMF) versus cyclosporine (CsA) combined with low-dose corticosteroids was evaluated in patients with idiopathic MN in a multi-center randomized trial (www.ClinicalTrials.gov NCT01282073).

METHODS

A total of 39 biopsy-proven idiopathic MN patients with severe proteinuria were randomly assigned to receive MMF combined with low-dose corticosteroids (MMF group) versus CsA combined with low-dose corticosteroids (CsA group), respectively, and followed up for 48 weeks. Complete or partial remission rate of proteinuria and estimated glomerular filtration rate (eGFR) at 48 weeks were compared.

RESULTS

The level of proteinuria at baseline and at 48 weeks was 8.9 ± 5.9 and 2.1 ± 3.1 g/day, respectively, in the MMF group compared to 8.4 ± 3.5 and 3.2 ± 5.7 g/day, respectively, in the CsA group. In total, 76.1% of the MMF group and 66.7% of the CsA group achieved remission at 48 weeks (95% confidence interval, -0.18 to 0.38). There was no difference in eGFR between the two groups. Anti-phospholipase A2 receptor Ab levels at baseline decreased at 48 weeks in the complete or partial remission group (P = 0.001), but were unchanged in the no-response group. There were no significant differences between the two groups in changes in the Gastrointestinal Symptom Rating Scale and Gastrointestinal Quality of Life Index scores from baseline to 48 weeks.

CONCLUSION

In combination with low-dose corticosteroids, the effect of MMF may not be inferior to that of CsA in patients with idiopathic MN, with similar adverse effects including gastrointestinal symptoms. Trial registry at ClinicalTrials.gov (NCT01282073).

Reporting renal biopsies from Cyprus: a systematic approach

Background:

The etiology of renal disease varies in different parts of the world. In the Middle East, half of all patients reaching end-stage are categorised as either unknown etiology or hypertension-related nephropathy.

Objectives:

To report a renal biopsy series, in a reproducible format and manner, so that data can be compared directly among other series.

Patients and Methods:

Biopsies of native kidneys were performed in a 10-year period, at a tertiary referral hospital that provides the entire nephrology service for north Cyprus. Data are reported from 153 patients older than 17 years, who were either Turkish-Cypriot or from the Turkish mainland.

Results:

Mean biopsy rate was 48 per million population (pmp) per year. Mean age was 45.7 years (range 18-78). Overall, the sex distribution was similar (male 51%). The most common histopathological categories were primary glomerulonephritis (GN) (56%), secondary GN (27%), and tubulo-interstitial disease (14%). Of those with primary GN, 29% had secondary (2o) focal and segmental glomerulosclerosis (FSGS) (29%), followed by IgA nephropathy (24 %), membranous 18% and a further 11 patients with 1o FSGS (12%). The incidence of IgA nephropathy was 6.3 per pmp/year. When expressed as a percentage of the annual biopsy rate, 14% of all biopsies showed IgA nephropathy.

Conclusions:

To compare data among centres, they must be expressed in terms of the population (incidence pmp/year) and the biopsy rate. In our population, secondary FSGS is common and uncharacterised and we believe many will be caused by monogenic disease.

Epidemiology of biopsy-proven glomerulonephritis in Queensland adults

AIM

There is a paucity of data pertaining to the incidence of biopsy-proven glomerulonephritis (GN) in Australia. This retrospective study aims to review the data from all adult native renal biopsies performed in the state of Queensland from 2002 to 2011--comparing results with centres from across the world.

METHODS

Pathology reports of 3697 adult native kidney biopsies were reviewed, of which 2048 had GN diagnoses. Age, gender, clinical indication and histopathology findings were compared.

RESULTS

The average age at biopsy was 48 ± 17 years. Male preponderance was noted overall (∼60%), with lupus nephritis being the only individual GN with female predilection. The average rate of biopsy was 12.04 per hundred thousand people per year (php/yr). Nephrotic and nephritic syndromes comprised approximately 75% of all clinical indications that lead to GN diagnoses. IgA nephropathy (1.41 php/yr) was the most common primary GN followed by focal segmental glomerulosclerosis (1.02 php/yr) and crescentic GN (0.73 php/yr). Diabetic nephropathy (0.84 php/yr), lupus nephritis (0.69 php/yr) and amyloidosis (0.19 php/yr) were the most commonly identified secondary GN.

CONCLUSION

IgA nephropathy is the predominant primary GN in Queensland, and nephrotic syndrome the most common indication for a renal biopsy. While crescentic GN incidence has significantly increased with time, focal segmental glomerulosclerosis incidence has not shown any trend. Incidence of GN overall appears to increase with age. The annual rate of biopsy in this study appears lower than previously published in an Australian population.

Biopsy-proven kidney diseases in the elderly: clinical characteristics, renal histopathological spectrum and prognostic factors

Objective

To explore the clinical characteristics, renal histopathological spectrum and prognostic factors of biopsy-proven kidney diseases in the elderly.

Methods

A retrospective observational study was conducted in elderly patients who had received renal biopsies. Demographic, clinical and pathological data at the time of the biopsy were collected from the medical records. Follow-up records and prognostic factors were studied.

Results

The elderly (≥60 years) accounted for 74 of 434 (17.1%) native renal biopsies that were performed in a 9-year period. In the cohort of included elderly patients (n = 72), the prevalence of nephrotic syndrome and acute kidney injury was 62.5% (45 of 72) and 40.3% (29 of 72), respectively. For elderly patients with primary glomerular diseases (n = 44), membranous nephropathy was the most frequent pathological type (24 of 44; 54.5%). For elderly patients with secondary glomerular diseases (n = 25), anti-neutrophil cytoplasmic antibody-associated vasculitis was the most frequent aetiology (nine of 25; 36.0%). Requirement for renal replacement therapy (RRT) was an independent risk factor for poor prognosis.

Conclusions

Kidney diseases in the elderly have distinctive characteristics. Requirement for RRT was associated with poor prognosis in the elderly with biopsy-proven kidney diseases.

[Renal needle biopsy in the Department of Nephrology in Fès: indications and results in 522 cases]

L'apport de la ponction biopsie rénale (PBR) dans le diagnostic, le choix thérapeutique et l’évaluation pronostique des néphropathies est considérable. Aucune étude marocaine n'a évalué la pratique et l'apport de la PBR. Notre objectif est d’étudier les indications de la PBR, déterminer la fréquence des maladies rénales identifiées par PBR dans notre région et de faire une confrontation entre les données clinico-biologiques et le diagnostic historique. Notre étude menée entre Janvier 2009 et Décembre 2012, est rétrospective. Nous avons inclus tous les patients du service de Néphrologie du CHU Hassan II de Fès ayant bénéficié d'une biopsie de reins natifs. 522 PBR ont été réalisées. Nous avons exclu 8 biopsies devant le manque de renseignements et avons donc retenu 514. L’âge moyen des patients au moment de la PBR est de 39 ±17 ans (3-82 ans). Le sex ratio est de 0,9. Le syndrome néphrotique est le diagnostic clinique le plus fréquent à tous les âges (58,2%). Les néphropathies glomérulaires représentent 94,2% des maladies rénales diagnostiquées, leur distribution varie selon l’âge des patients. La PBR a confirmé le premier diagnostic suspecté cliniquement dans 40,65% des cas, alors qu'elle a révélé un diagnostic inattendu chez 22,5% d'entre eux. Le diagnostic syndromique permet d'orienter vers la maladie rénale la plus probable et de guider les thérapeutiques urgentes en attendant les résultats de la PBR. Mais il ne peut en aucun remplacer la PBR qui reste le gold standard.

Biopsy-proven renal disease in Ile-Ife, Nigeria: A histopathologic review

Although various patterns of renal diseases have been reported from different renal biopsy registries worldwide, data from Nigeria remain scanty. A 10-year retrospective review of renal biopsies was conducted in our tertiary health care facility. All cases were reclassified based on their light microscopic features after the application of standard histochemical stains. A total of 165 cases were reviewed with a male:female ratio of 1.8:1 and a mean age of 15.4 ± 12.0 years. About 69.7% of the cases were below the age of 16 years, while only 2.4% were older than 50 years. The most common indications for biopsy were nephrotic syndrome (72.1%) and acute renal failure of unknown etiology (11.5%). Overall, glomerulonephritis (80%) was the most common histologic category and occurred only in individuals younger than 50 years old. Minimal change disease (22.9%) and membranoproliferative glomerulonephritis (21.9%) were the most common varieties in children, while membranous glomerulonephritis (30.6%) and focal segmental glomerulosclerosis (27.8%) were the commonest among the adult population. The initial histologic diagnosis was revised in 18 cases while a diagnosis was arrived at in seven cases initially adjudged as inadequate for assessment. This study showed that renal biopsy was predominantly performed in children and adolescents. Although glomerulonephritis was the predominant disease, the predominant histologic patterns varied with the patient age. Despite the scarcity of advanced diagnostic tools in resource-poor environments, routine use of histochemical stains is helpful in the evaluation of renal biopsies.

Insight to changing morphologic patterns of glomerulopathy in adult Pakistani patients: an institutional perspective

Background

Idiopathic nephrotic syndrome encompasses diverse histogenetic patterns and depicts socioeconomic and demographic differences attributable to genetic profile, environmental factors and prevalence of infectious diseases. A lack of renal registry in our country necessitates a need to document changing histologic patterns of nephrotic syndrome as noted in different parts of the world.

Methods

We retrospectively analyzed 140 patients who underwent renal biopsy at Liaquat National Hospital from January 2009 to December 2013 over a period of 3 years. On the basis of clinical profile cases were segregated into nephritic and nephrotic syndrome and histologic and immunoflourescence findings were analyzed.

Results

Among 140 cases of glomerulonephritis diagnosed in the study period, 98 cases (70 %) were those of primary glomerulonephritis and 42 were of secondary glomerulopathy (30 %). Membranous glomerulonephritis was the most common primary glomerulonephritis (33.6 %) followed by focal segmental glomerulosclerosis FSGS (20.4 %), whereas lupus nephritis is the most common secondary glomerulopathy (47.6 %) followed by amyloidosis and diabetic glomerulosclerosis (16.6 % each).

Conclusion

We found a considerable high incidence of membranous glomerulonephritis and FSGS in our population that entails a need to investigate prevalence of associated factors like Hepatitis B and HIV infections in population at risk. Moreover, renal biopsy registry would be instrumental in this regard to record changing disease pattern in this part of the world.

Haematuria on the Spanish Registry of Glomerulonephritis

Recent studies suggest a pathogenic role for glomerular haematuria among renal function. However, there is no data on the prevalence of haematuria from a large renal biopsy registry. We analysed the prevalence of gross (GH) and microscopic (mH) haematuria in 19,895 patients that underwent native renal biopsies from the Spanish Registry of Glomerulonephritis. Haematuria's overall incidence was 63% (GH 8.6% and mH 55.1%), being more frequent in males (64.7% vs. 62.4%). GH was more prevalent in patients <18 years (21.3% vs. 7.7%). The commonest clinical presentation associated with GH was acute kidney injury (31.5%) and IgA Nephropathy (IgAN) (33.6%) was the most frequent histological finding. GH patients showed a significantly (p < 0.05) lower eGFR and proteinuria levels as compared with patients with mH and without haematuria. Moreover, mH was more prevalent in adults (56.3%). Nephrotic syndrome was the commonest clinical presentation in mH patients (32.2%) and IgAN (18.5%) the most frequent histological finding. In conclusion, haematuria, is a frequent urinalysis finding in patients underwent native renal biopsy. The most frequent histological finding in both GH and mH is IgAN. Whereas, GH is more frequent in young males with acute kidney injury, mH is commoner among adults with nephrotic syndrome.

Pediatric Renal Biopsies in India: A Single-Centre Experience of Six Years

Background:

Renal biopsy is a well-established diagnostic modality for the assessment of kidney diseases in children. It can provide diagnostic precision and prognostic value and guide in therapeutic options for many renal diseases.

Objectives:

This report describes the indication, histopathological patterns, and epidemiology of renal diseases in children in India.

Patients and Methods:

This is a single-center study on renal biopsies performed between January 2008 and December 2013 in 346 children (age ≤ 14 years).

Results:

Eleven (3.17%) biopsies were inadequate, and 335 biopsies were considered for analysis. The mean age was 7.91 ± 3.04 years with a predominance of males (68.1%). Nephrotic syndrome (46.2%) was the most common indication, followed by urinary abnormality (41.19%), acute nephritic syndrome (10.74%), and chronic renal failure (1.79 %). Primary glomerulonephritis (GN) was predominant (81.79%), and secondary GN constituted 16.12% of the biopsies. Primary GN included mesangial proliferative GN (MePGN), IgM nephropathy, focal segmental glomerulosclerosis, minimal change disease, IgA nephropathy, membranoproliferative GN, membranous nephropathy, crescentic GN, and post-infectious GN. Secondary GN revealed lupus nephritis, hemolytic uremic syndrome, amyloidosis, and hypertensive nephropathy. Tubulointerstitial nephritis was observed in 2.08%. The most common histological pattern of primary GN was MePGN (20%) and in secondary GN it was lupus nephritis (7.76%).

Conclusions:

The present study provides data on the epidemiology of renal diseases in children in India and will be helpful for developing a national registry and devising therapeutic guidelines.

Acute interstitial nephritis - a reappraisal and update

Acute interstitial nephritis (AIN) is an under recognized and under diagnosed cause of acute kidney injury (AKI). It is estimated to account for 15 - 20% of cases of AKI; it is the reported diagnosis in 2.8% of all kidney biopsies, and 13.5% of biopsies done specifically for acute renal failure. Considerable evidence implicates antigen initiated cell-mediated injury in the pathogenesis of AIN. Drugs account for 70% of all cases, with over 150 different agents incriminated. The remaining cases are due to infections, autoimmune diseases, and rarely idiopathic. The central component of renal injury in AIN is altered tubular function, which usually precedes decrements in filtration rate. The key to early diagnosis is vigilance for the presence of tubular dysfunction in non-oliguric individuals, especially in patients with modest but gradual increments in creatinine level. The utility of urinary biomarkers to diagnose AIN in its early nascent and potentially reversible stage remains to be determined. Prompt recognition, elimination of the offending source of antigen, and use of a limited course of steroid therapy where indicated, will result in complete resolution in ~ 65% of cases, partial resolution in up to 20%, and irreversible damage in the rest.

Changes in the aetiology, clinical presentation and management of acute interstitial nephritis, an increasingly common cause of acute kidney injury

Acute interstitial nephritis (AIN) is an important cause of acute kidney injury that has experienced significant epidemiological and clinical changes in the last years. The classical presentation, mostly induced by antibiotics and accompanied by evident hypersensitivity manifestations (skin rash, eosinophilia, fever) has been largely replaced by oligosymptomatic presentations that require a higher index of suspicion and are increasingly recognized in the elderly, having non-steroidal anti-inflammatory agents and proton pump inhibitors as frequent offending drugs. Drug-induced AIN continues to be the commonest type, but it requires a careful differential diagnosis with other entities (tubulointerstitial nephritis with uveitis syndrome, IgG4-related disease, drug reaction with eosinophilia and systemic symptom syndrome, sarcoidosis and other systemic diseases) that can also induce AIN. Cortico-dependant, relapsing AIN is a recently recognized entity that poses an important therapeutic challenge. Although corticosteroids are widely used in drug-induced AIN to speed kidney function recovery and avoid chronic kidney disease, their efficacy has not been tested by randomized controlled trials. New diagnostic tests and biomarkers, as well as prospective therapeutic studies are needed to improve AIN diagnosis and management.

The calcineurin inhibitor tacrolimus reduces proteinuria in membranous nephropathy accompanied by a decrease in angiopoietin-like-4

Tacrolimus is an anticalcineurinic agent with potent immunosuppressive activity that has recently been shown to have the added benefit of reducing proteinuria in membranous nephropathy (MN) patients. However, its potential mechanisms remain unknown. To reveal the mechanism, rat cohorts were administered tacrolimus or vehicle from days 7 to 28 after the induction of passive Heymann nephritis (PHN). PHN induction resulted in heavy proteinuria and increased expression of desmin, a marker of injured podocytes. We also showed that the glomerular expression of angiopoietin-like-4 (Angptl4) was markedly upregulated in PHN rats and human MN followed by an increase in urine Angptl4 excretion. In addition, increased Angptl4 expression may be related to podocyte injury and proteinuria. Furthermore, upregulated Angptl4 expression primarily colocalized with podocytes rather than endothelial or mesangial cells, indicating that podocytes may be the source of Angptl4, which then gradually migrated to the glomerular basement membrane over time. However, tacrolimus treatment markedly reduced glomerular and urinary Angptl4, accompanied by a reduction in the established proteinuria and the promotion of podocyte repair. Additionally, glomerular immune deposits and circulating IgG levels induced by PHN clearly decreased following tacrolimus treatment. In conclusion, this is the first demonstration that the calcineurin inhibitor tacrolimus can reduce Angptl4 in podocytes accompanied by a decrease in established proteinuria and promotion of podocyte repair in MN.

Nationwide biopsy survey of renal diseases in the Czech Republic during the years 1994-2011

BACKGROUND

We describe data on 10,472 renal biopsies gathered by the Czech Registry of Renal Biopsies over a period of 18 years.

METHODS

We assessed the main demographic, clinical and histological data of individuals who underwent renal biopsies of native kidneys in 31 centers in the Czech Republic (population 10.3 million) during the period 1994-2011.

RESULTS

We evaluated 10,472 renal biopsies: males 57.8%, children (≤15 years) 13.6%, elderly (>60 years) 19.1%. The most frequent biopsy-proven diseases were primary (55.7%) and secondary (29.1%) glomerulonephritides (GN). Tubulointerstitial nephritis (TIN) was observed in 3.4 % and vascular diseases in 4.1%. The samples were non-diagnostic in 4.2%. Among primary GN the most frequent diagnoses were IgA nephropathy (IgAN) (37.4%), membranous GN (MGN) (13%) and focal segmental glomerulosclerosis (FSGS) (12.6%). Among secondary GN, systemic lupus erythematosus (SLE) represented 23.2%, hereditary diseases 19.8% and necrotizing vasculitis (NV) 19.4%. Among adults, mild renal insufficiency [serum creatinine (SCr) 111-200 μmol/l] was present in 24.7%, advanced renal insufficiency (SCr 201-400 μmol/l) in 15.3, and 12.3% of patients had SCr > 400 μmol/l. The most common diseases in patients with nephrotic proteinuria were minimal change disease (MCD) (39.7%) among children, IgAN (26.2%) in adults aged 16-60 years and amyloidosis (42.7%) among the elderly. The mean annual incidence (per million population) was: primary GN 30.9, secondary GN 18.1, IgAN 11.6, MGN 4.0, SLE 4.0, FSGS 3.9, MCD 3.4, NV 3.2, diabetic nephropathy 2.3, thin basement membrane glomerulopathy 2.0, mesangioproliferative GN 1.9, and TIN 1.9. Ultrasound needle guidance was used in 66.8%. The frequency of serious complications (symptomatic hematoma, gross hematuria, blood transfusion) was approximately 3.2%.

CONCLUSIONS

This report provides representative population-based data on native biopsy-proven renal diseases in the Czech Republic. Over the 18 years of nationwide biopsy survey, we noted an increase of the mean age of renal biopsy cases, an increasing proportion of elderly, and a cardinal change in biopsy technique towards ultrasonography needle guidance.

Pathological patterns of primary nephrotic syndrome in Central China: a retrospective study of 627 cases

BACKGROUND

The pathological patterns underlying PNS in adult are poorly studied in Central China.

METHODS

This is a retrospective analysis of the clinical and pathologic data involving 627 adult patients with PNS who have been finished the renal biopsies from January 2009 to September 2012 in XiangYa 2nd Hospital of Central South University. Patients enrolled in our study were all from Central China.

RESULTS

There were 379 males and 248 females, formed the ratio of 1.53:1. There existed three main sorts of pathological patterns underlying PNS: membranous nephropathy (MN) 26.63%, minimal change disease (MCD) 23.60%, IgA nephropathy (IgAN) 23.39%. Among all biopsies, the proportion of FSGS underlying PNS increased from 5.8% during the period from 2009 to 2010 to 14.7% during the period from 2011 to 2012. The most common complication of PNS was infectious diseases, and MCD underlying PNS ran a higher risk of encountering acute renal injury. IgAN had the highest incidence of hematuresis. The common pathological patterns of PNS differed in age-brackets: IgAN and MCD were the main pathological lesions in patients aged from 16 to 30 years; MN mostly occurs in patients over 30. MCD was the dominating pathological lesions underlying IgAN which expressed as PNS.

CONCLUSIONS

(1) MN was the most frequent pathological pattern underlying PNS, the proportion of FSGS underlying PNS increased during the last 2 years. (2) The common pathological patterns of PNS differed in age-brackets and pathological patterns correlated to the complications or comorbidities of PNS to some extent.

Lupus in Africa: can we dispel the myths and face the challenges?

The epidemiology of systemic lupus erythematosus (SLE) in Africa is largely undetermined, and the perception persists that the incidence of SLE on the continent is very low. Recent studies as well as our own experience, however, suggest that this is not the case. We have conducted a survey amongst medical practitioners in Africa to determine their experiences of diagnosing and treating SLE patients, and the results suggest that significant numbers of African patients are presenting with SLE. The apparent low incidence rate in Africa may be the result of underdiagnosis due to poor access to health care, low disease recognition within primary health care settings, limited access to diagnostic tools and inadequate numbers of specialist physicians. Treatment of SLE in Africa is also restricted by availability and affordability of immunosuppressive drugs. We have established the African Lupus Genetics Network (ALUGEN), an informal network of clinicians and researchers in Africa who have an interest in SLE, in order to facilitate combined clinical and research efforts towards improved outcomes for African SLE patients.

Changes in the histological spectrum of glomerular diseases in the past 16 years in the North-Eastern region of Romania

BACKGROUND

The aim of this study was to describe the findings of renal biopsies from a large nephrology center in Iasi, Romania, performed between 2005 and 2010. We compared these findings with our previous ones, from 1995 to 2004, as well as with similar reports.

METHODS

We studied retrospectively 239 renal biopsies. The indications for renal biopsy were categorized into: nephrotic syndrome, acute nephritic syndrome, asymptomatic urinary abnormalities, acute kidney injury, and chronic kidney disease of unknown etiology.

RESULTS

During the past 16 years, a gradual increase in the annual number of renal biopsies/per million population (p.m.p.)/year was observed, although this incidence remained lower than in other European countries. Nephrotic syndrome was the indication for renal biopsy in over 50% of cases. Glomerulonephritis (GN) was the main histological diagnosis in 91% of cases, of which 56% were primary GN and 35% were secondary GN. The frequency of various types of primary GN was: membranoproliferative GN (MPGN) - 29.3%, membranous nephropathy (MN) -27.5%, focal segmental glomerulosclerosis (FSGS) - 17.2%, mesangial GN (including IgAN) -13.7%, crescentic GN - 9.4%, and minimal change disease (MCD) - 2.5%. Compared to the previously reported period (1994-2004), we observed a significant decrease in the frequency of MPGN and significant increases in the frequency of FSGS and, particularly MN - which more than doubled.

CONCLUSION

We report significant changes in the histological spectrum of GN in North-Eastern Romania in 2005-2010, compared to the previously reported 10-yrs. These changes seem to be following a trend that has also been observed in Western countries a few decades ago, and which may have a socioeconomic explanation.

Epidemiologic data of adult native biopsy-proven renal diseases in Croatia

PURPOSE

There is a paucity of epidemiological data on biopsy-proven renal disease in Croatia. The purpose of this report is a review of clinical and histological data, over a period of 15 years, from the single biggest adult native renal biopsy center in Croatia.

METHODS

This report includes data from 922 adult native renal biopsies in patients referred from the whole country and performed in our center from 1996 till February 2012. Data on age, gender, serum creatinine, urine sediment, 24-h proteinuria, clinical syndrome and histological diagnosis were collected and analyzed retrospectively. In all patients, light, immunofluorescence and electron microscopic analysis was performed.

RESULTS

The median age of the patients was 48 years (interquartile range 36-59 years), and the majority of patients were men (57.8 %). The most common indication for renal biopsy was nephrotic syndrome (40.3 %) followed by asymptomatic urinary abnormalities (31.7 %). The most common biopsy-proven renal disease in total was IgA glomerulonephritis (19.3 %), followed by focal segmental glomerulosclerosis (FSGS) (15.8 %) and membranous glomerulonephritis (9.2 %). In men, similar results were found, while in women, the most common were hereditary nephritis (13.4 %), FSGS (12.9 %) and connective tissue disease-related glomerular disorders (11.6 %).

CONCLUSION

The presented data are an important contribution to the better understanding of the epidemiology of biopsy-proven renal disease in Croatia and Europe throughout comparison with other registry data. This data should be the basis for the formation of Croatian Registry of Renal Biopsies.

Mortality and renal outcome of primary glomerulonephritis in Korea: observation in 1,943 biopsied cases

BACKGROUND

Previous epidemiological studies have focused on the prevalence of primary glomerulonephritis (GN), but few have explored long-term patient outcomes. This study was conducted to investigate the long-term patient and renal outcomes of primary GN.

METHODS

A total of 1,943 biopsy-proven primary GN patients were included. The outcomes were mortality and end-stage renal disease (ESRD) progression. The relative mortality rate was expressed by the standardized mortality ratio (SMR) and the 95% confidence interval (CI).

RESULTS

During the median follow-up of 90 months, 325 (16.7%) patients progressed to ESRD and 164 (8.4%) patients died. Patients with minimal change disease exhibited the best renal and patient outcomes, whereas those with membranoproliferative GN had the worst. IgA nephropathy patients appeared to have a good survival rate in spite of their considerable progression to ESRD, and focal segmental glomerulosclerosis patients showed poor renal and patient outcomes. Mortality was 67% higher in primary GN patients than in the age- and sex-matched general population (SMR, 1.67; 95% CI, 1.42-1.95). The difference was more prominent in women (SMR, 2.95; 95% CI, 2.27-3.77) than in men (SMR, 1.31; 95% CI, 1.07-1.60). Renal risk factors, e.g. hypertension, proteinuria and initial renal dysfunction, were all associated with higher mortality, and the relative mortality rate increased with the number of risk factors.

CONCLUSIONS

In patients with primary GN, mortality is significantly higher than in the age-/sex-matched general population, especially in women. Moreover, the presence of renal risk factors is positively associated with both relative mortality and progression to ESRD.

Glomerular diseases in the Military Hospital of Morocco: Review of a single centre renal biopsy database on adults

Epidemiological studies provide useful information for clinical practice and investigations. This report aimed to determine glomerular diseases frequencies in a region of Morocco. All native renal biopsies (January 2000 to December 2007) on adults were reviewed, but only glomerular diseases were analyzed. The diagnosis of each case was based on histological, immunopathological and clinical features. We have performed 171 renal biopsies in 161 patients (101 males and 60 females), the mean age was (range) 40.4 ±15 years (16-72). Clinical indications that lead to renal biopsy were: nephrotic syndrome (60.3%), renal failure of unknown aetiology (31.6%), asymptomatic urinary abnormalities (6.2%) and nephritic syndrome(1.9%). Primary glomerular diseases were reported in 84 patients (52%). The most common histological lesion was minimal change disease (26%). Idiopathic membranous glomerulopathy was the second most common lesion (23%) followed by membranoproliferative glomerulonephritis (17%), IgA nephropathy (12%), focal and segmental glomerulosclerosis (9.4%) and crescentic glomerulonephritis (6%). Secondary glomerular diseases were reported in 53 patients (33%). Lupus nephritis was the secondary glomerular disease most frequent (45%) followed by amyloïdosis (19%), diabetic nephropathy (15%), and Good pasture's syndrome (7.6%). The most common complications of the procedure were pain at biopsy site in 4%, gross hematuria in 11.1%, perirenal hematoma in 5% and hematuria requiring nephrectomy in 0.6% patients. Minimal change disease was the most frequent primary glomerulopathy and lupus nephritis was the most frequent secondary glomerulopathy in our group. The reasons for these findings are unclear. This information is an important contribution to the understanding the prevalence of renal diseases in North Africa.

Occurrence of kidney diseases and patterns of glomerular disease based on a 10-year kidney biopsy material: a retrospective single-centre analysis in Estonia

OBJECTIVE

Kidney biopsy is an important diagnostic tool in assessing glomerular damage. This study aimed to determine the occurrence of glomerular disease during the past decade at a single centre, to assess potential changes in the structure of primary glomerulopathies over time, and to define gender- and age-related differences.

MATERIAL AND METHODS

A total of 578 consecutive native kidney biopsies during the period 2000-2010 was retrospectively reviewed at Tartu University Hospital, Estonia. Biopsies were evaluated according to clinical data with standard histological methods.

RESULTS

The patients' mean age was 39.9 ± 17.9 (range 4-87) years. Less than half of informative kidney biopsies (n = 547) comprised primary glomerulopathies (45.4%), the patients' mean age was 38.7 ± 17.7 (4-79) years and the predominant group comprised male patients. Secondary glomerulopathies made up 22.3%, tubulointerstitial diseases 8.2% and other conditions 24.1%. Among primary glomerulopathies, inflammatory damage to glomeruli dominated (63.4%), whereas immunoglobulin A (IgA) nephropathy was the most common disease (35.5%). Non-inflammatory diseases of glomeruli made up 34.6%, among which the most common was focal and segmental glomerulosclerosis (16.1%), followed by minimal change disease (14.1%). Membranoproliferative glomerulonephritis was a rare form of glomerular damage among primary glomerulopathies (7.7%). Comparison between male and female cases in the primary glomerulopathies group revealed a statistically significant difference in their frequency (p = 0.01).

CONCLUSIONS

Inflammatory glomerulopathies mostly prevailed in the spectrum of primary glomerulopathies. IgA nephropathy was the most common glomerulopathy. Comparing the data with those from a 15-year earlier period at the same centre, a change towards non-inflammatory glomerulopathies was noticed.

Renin-angiotensin system inhibitors reduce the progression of mesangioproliferative glomerulonephritis: 10 year follow-up

BACKGROUND

Proteinuria is a common presentation of mesangioproliferative glomerulonephritis (MsPGN). No studies are available on the long-term effect of treatment by renin-angiotensin system (RAS) inhibitors on renal outcome in MsPGN patients. This study prospectively evaluates the effects of RAS inhibitors on renal outcome in patients with low risk MsPGN followed up for 10 years using historical patients with similar features at the time of presentation as untreated controls.

ENDPOINTS

decrease of basal proteinuria>20% and loss>20% of basal glomerular filtrate rate (GFR) at the end of first year of observation. The patients were re-evaluated bimonthly during the first year and every 6 months thereafter.

RESULTS

Twenty-five patients fulfilled the selection criteria. After one year follow-up 19 patients reached the endpoint of proteinuria and no patient reached the endpoint of GFR. No significant change in blood pressure levels (BP) and GFR was registered, by contrast daily proteinuria decreased significantly (p<0.001), falling by 29% at sixth month and 47% at the end of the follow-up. The historical control group consisted of 15 untreated patients seen between 1987 and 1992. The two-way analysis of variance for repeated measures showed greater values of GFR (p<0.001) and lower levels of daily proteinuria (p<0.001) in treated patients as compared to untreated controls.

CONCLUSIONS

This 10-year follow-up study indicates that the early treatment with RAS inhibitors at low doses favourably influences the long-term renal outcome in proteinuric patients with MsPGN. Limitations were the small sample size and lack of randomization.

Non-IgA mesangioproliferative glomerulonephritis: a benign entity?

BACKGROUND

Non-IgA mesangioproliferative glomerulonephritis is a well recognized but less studied entity. The clinical manifestations, treatment response and long-term outcome have not been clearly defined.

METHODS

This single-centre study included patients with biopsy-proven non-IgA mesangioproliferative glomerulonephritis who had been on regular follow-up for >3 years. Their clinical features at presentation, response to therapy and long-term renal outcome are addressed in this study.

RESULTS

Nephrotic syndrome developed in 51 of 57 patients (89.4%). The majority of them--34 of 51(80%)--were steroid sensitive and had either infrequent or no relapse. However, steroid-dependent nephrotic syndrome occurred in eight patients (15.6%), while steroid resistance occurred in nine patients (17.6 %). Thirteen patients developed chronic kidney disease (CKD) with three progressing to end-stage renal disease, three to CKD Stage 4 and seven to CKD Stage 3.

CONCLUSIONS

Non-IgA mesangioproliferative glomerulonephritis is a disease, which is not benign, and is associated with significant treatment-related morbidity.

Pattern of biopsy-proven renal disease in a single center of south India: 19 years experience

The prevalence of biopsy-proven glomerulonephritis varies according to the geographic area, socioeconomic condition, race, age, demography and indication of renal biopsy. This study analyzed the distribution of biopsy-proven renal disease (BPRD) and its changing pattern over a period of 19 years from a tertiary care hospital in south India. All the renal biopsies performed from 1990 to 2008 were reviewed retrospectively. Biopsies were evaluated by light microscopy and immunofluorescence microscopy and also special stains when warranted. A total of 1849 biopsies were analyzed. The mean patient age was 32.27 ± 18.38 (range 10-80) years. The male:female ratio was 1.4:1. The most common indications of renal biopsy were nephrotic syndrome (49%), followed by chronic renal failure (13.6%) and rapidly progressive renal failure (12%). Primary glomerulonephritis (PGN) comprised 1278 (69.1%) of the total patients. Among the PGN cases, the most common one was minimal change disease (21.8%), followed by focal segmental glomerulosclerosis [FSGS (15.3%)], membranous glomerulonephritis (10%), chronic glomerulonephritis (9.7%), postinfectious glomerulonephritis (8.1%), mesengioproliferative glomerulonephritis (7.5%), diffuse proliferative glomerulonephritis (6.7%), crescentic glomerulonephritis (6.5%), IgA nephropathy [IgAN (6.3%)], membranoproliferative glomerulonephritis (5.7%), focal proliferative glomerulonephritis (1.6%) and IgM nephropathy (0.5). Secondary glomerular disease (SGN) accounted for 337 (18.2%) of the cases. The most common SGN was lupus nephritis (80.1%), followed by amyloidosis (8%) and diabetic nephropathy (6.5%). Tubulointerstitial disease [124 (6.7%)] and vascular disease [60 (3.2%)] were less common. End-stage changes and miscellaneous disease were found in 37 (2%) and 13 (0.7%) cases, respectively. The incidence of FSGS and IgAN has been increasing since 1999. This study provides descriptive biopsy data and highlights the changing incidence of renal disease which is probably contributed by an increase referral due to increased awareness together with increased manpower and infrastructure.

Japan Renal Biopsy Registry: the first nationwide, web-based, and prospective registry system of renal biopsies in Japan

BACKGROUND

The Committee for the Standardization of Renal Pathological Diagnosis and the Working Group for Renal Biopsy Database of the Japanese Society of Nephrology started the first nationwide, web-based, and prospective registry system, the Japan Renal Biopsy Registry (J-RBR), to record the pathological, clinical, and laboratory data of renal biopsies in 2007.

METHODS

The patient data including age, gender, laboratory data, and clinical and pathological diagnoses were recorded on the web page of the J-RBR, which utilizes the system of the Internet Data and Information Center for Medical Research in the University Hospital Medical Information Network. We analyzed the clinical and pathological diagnoses registered on the J-RBR in 2007 and 2008.

RESULTS

Data were collected from 818 patients from 18 centers in 2007 and 1582 patients from 23 centers in 2008, including the affiliated hospitals. Renal biopsies were obtained from 726 native kidneys (88.8%) and 92 renal grafts (11.2%) in 2007, and 1400 native kidneys (88.5%) and 182 renal grafts (11.5%) in 2008. The most common clinical diagnosis was chronic nephritic syndrome (47.4%), followed by nephrotic syndrome (16.8%) and renal transplantation (11.2%) in 2007. A similar frequency of the clinical diagnoses was recognized in 2008. Of the native kidneys, the most frequent pathological diagnosis as classified by pathogenesis was immunoglobulin (Ig) A nephropathy (IgAN) both in 2007 (32.9%) and 2008 (30.2%). Among the primary glomerular diseases (except IgAN), membranous nephropathy (MN) was the most common disease both in 2007 (31.4%) and 2008 (25.7%).

CONCLUSIONS

In a cross-sectional study, the J-RBR has shown IgAN to be the most common disease in renal biopsies in 2007 and 2008, consistent with previous Japanese studies. MN predominated in the primary glomerular diseases (except for IgAN). The frequency of the disease and the clinical and demographic correlations should be investigated in further analyses by the J-RBR.