Histopathologic Characteristics of Childhood Nephrotic Syndrome in a Tertiary Health Facility in Nigeria.

BACKGROUND: Globally, the predominant histopathologic characteristic of childhood nephrotic syndrome has been minimal change nephropathy (MCN). However, some studies from Africa and Nigeria have revealed otherwise. It is imperative that this pattern is re-examined from time to time given changing disease and environmental dynamics from place to place. OBJECTIVE: This study aimed to determine the histopathological characteristics of childhood nephrotic syndrome in Ilorin, northcentral Nigeria. METHODS: A prospective study of all new patients aged 2-14 years who presented with clinical features of nephrotic syndrome between January 2010 to December 2023 at the University of Ilorin Teaching Hospital, Ilorin was carried out. All eligible patients underwent renal biopsy. RESULTS: A total of 47 children with nephrotic syndrome were biopsied comprising of 21 males and 26 females making an M: F ratio of 1:1.2. The age range of subjects was 2-14 years with a mean of 7.8 ±3.6 years. The most common histological type of nephrotic syndrome was minimal change nephrotic syndrome (MCNS) which occurred in 35(74.5%) children followed by membranoproliferative glomerulonephritis (MPGN) in 5(10.6%) and focal segmental glomerulosclerosis (FSGS) in 2(4.3%). Of the 35 MCNS patients, 31(88.6%) were steroid sensitive while 4(11.4%) were steroid resistant. CONCLUSION: The predominant histopathological characteristic of childhood nephrotic syndrome was minimal change nephrotic syndrome, which was mostly steroid-sensitive.

CONTEXTE: Au niveau mondial, la principale caractéristique histopathologique du syndrome néphrotique de l'enfant a été la néphropathie à lésions minimales (NLM). Cependant, certaines études en Afrique et au Nigeria ont montré des résultats différents. Il est essentiel de réévaluer ce modèle régulièrement en raison de l'évolution des maladies et de l'environnement d'un endroit à l'autre. OBJECTIF: Cette étude visait à déterminer les caractéristiques histopathologiques du syndrome néphrotique de l'enfant à Ilorin, dans le nord-centre du Nigeria. MÉTHODES: Une étude prospective de tous les nouveaux patients âgés de 2 à 14 ans présentant des signes cliniques de syndrome néphrotique entre janvier 2010 et décembre 2023 à l'hôpital universitaire d'Ilorin, à Ilorin, a été réalisée. Tous les patients éligibles ont subi une biopsie rénale. RÉSULTATS: Au total, 47 enfants atteints du syndrome néphrotique ont été biopsiés, dont 21 garçons et 26 filles, soit un ratio H/F de 1/1,2. La tranche d'âge des sujets était de 2 à 14 ans avec une moyenne de 7,8 ± 3,6 ans. Le type histologique le plus fréquent du syndrome néphrotique était la néphropathie à lésions minimales (NLM), obser vée chez 35 (74,5 %) enfants, suivie de la glomérulonéphrite membranoproliférative (GMPN) chez 5 (10,6 %) et du sclérose segmentaire et focale (SSF) chez 2 (4,3 %). Parmi les 35 patients atteints de NLM, 31 (88,6 %) étaient cortico-sensibles et 4 (11,4 %) cortico-résistants. CONCLUSION: La principale caractéristique histopathologique du syndrome néphrotique de l'enfant était la néphropathie à lésions minimales, qui était principalement cortico-sensible. MOTS-CLÉS: Syndrome néphrotique, Enfant, Histopathologie, Nigeria.

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

BACKGROUND: Membranoproliferative glomerulonephritis (MPGN) is a rare glomerular injury that causes nephrotic syndrome and end-stage kidney disease. The nationwide demographics and treatment of Japanese patients with primary MPGN have not yet been reported. METHODS: We collected clinical personal records of patients with primary MPGN between 2015 and 2018 from the national registry organized by the Japanese Ministry of Health, Labour, and Welfare and investigated the characteristics of primary MPGN throughout Japan. RESULTS: Of 258 patients with primary MPGN, 199 and 59 showed nephrotic and non-nephrotic syndrome, respectively. The median age at onset was higher in patients with nephrotic syndrome than in those with non-nephrotic syndrome (45 [24-63] vs. 35 [14-53] years, respectively; P = 0.010). The use of oral prednisolone was significantly higher in patients with nephrotic syndrome than in those with non-nephrotic syndrome (73.9% vs. 59.3%, respectively; P = 0.032). When patients were divided into three age groups: adolescent and young adult group (≤ 39 years; n = 80), middle adult group (40-64 years; n = 111), and older adult group (≥ 65 years; n = 67), the use of oral prednisolone, cyclosporine, and mizoribine was significantly higher in the adolescent and young adult group than in the middle adult group. The mean dosage of oral prednisolone and mizoribine showed no differences among the three age groups. CONCLUSION: The national registry of clinical personal records of primary MPGN could provide an informative insight into the characteristics, clinical features, and treatment approaches for patients with primary MPGN in Japan.

Clinical and histological features in pediatric and adolescent/young adult patients with renal disease: a cross-sectional analysis of the Japan Renal Biopsy Registry (J-RBR).

BACKGROUND: Only a few studies have investigated epidemiological and clinicopathological information regarding pediatric and adolescent and young adult (AYA) patients with renal disease. The purpose of this study was to clarify the differences and relationship of clinicopathological findings between pediatric and AYA patients using the Japan Renal Biopsy Registry (J-RBR). METHODS: This cross-sectional study analyzed data from patients registered in the J-RBR between 2007 and 2017. Clinicopathological findings at diagnosis were analyzed for 3,463 pediatric (age < 15 years) and 6,532 AYA (age 15-30 years) patients. RESULTS: Although chronic nephritic syndrome was the most common clinical diagnosis at age > 5 years, nephrotic syndrome was the most frequent diagnosis at age < 4 years. The most common pathological diagnosis as classified by pathogenesis in pediatric patients was primary glomerular disease (except IgA nephropathy), whereas IgA nephropathy was increased in AYA patients. Mesangial proliferative glomerulonephritis was the most common pathological diagnosis as classified by histopathology in both pediatric and AYA patients. Minor glomerular abnormalities were the most frequent histopathologic diagnoses of nephrotic syndrome in childhood, but their frequency decreased with age. CONCLUSION: To the best of our knowledge, this is the first report of clinicopathological features of pediatric and AYA patients in a large nationwide registry of renal biopsy. There were differences of clinical, pathological and histopathologic findings between pediatric and AYA patients.

Clinical and pathological analysis of renal biopsies of elderly patients in Northeast China: a single-center study.

PURPOSE: To identify the clinical characteristics, histopathological features, and prognosis of kidney disease in a large cohort of elderly patients from Northeast China. METHODS: We retrospectively analyzed the renal disease spectrum in 7,122 patients who underwent renal biopsies at the Second Hospital of Jilin University from 2006 to 2020. Patients were grouped according to age: below 60 years (non-elderly group, n = 5923) and at least 60 years (elderly group, n = 1199). The clinical and pathological characteristics of renal biopsy patients in the groups were analyzed using the t-test and chi-square test. RESULTS: Compared with the non-elderly group, the elderly group had significantly fewer patients with primary glomerulonephritis, but more patients with tubulointerstitial disorders (p < .05). The incidence of IgA nephropathy, mesangial proliferative glomerulonephritis, and lupus nephritis was significantly lower in elderly patients than in non-elderly patients. The incidence of membranous nephropathy, membranoproliferative glomerulonephritis, diabetic nephropathy, hypertensive nephropathy, systemic vasculitis-associated renal damage, and amyloid nephropathy was significantly higher in elderly patients than in non-elderly patients (p < .05). The incidence of perinephric hematoma (≥4 cm2) in elderly patients with renal biopsy was lower than that in non-elderly patients. We noted that 79.9% of primary glomerulonephritis patients who received immunosuppressive therapy showed a remission rate of 83.5%. CONCLUSION: The spectrum of kidney disease in the elderly is different from that in the younger population.

Outcomes of immunoglobulin-associated mesangiocapillary glomerulonephritis: A South African experience.

AIM: Immunoglobulin-associated mesangiocapillary glomerulonephritis is currently the most common biopsy-confirmed glomerulonephritis in Cape Town, South Africa. We aimed to determine the outcome of patients with a biopsy-confirmed diagnosis of immunoglobulin-associated mesangiocapillary glomerulonephritis at our centre. METHODS: A retrospective cohort study of adult patients was conducted from January 1, 2000 to December 31, 2016. The endpoint was a composite of doubling of creatinine and/or end-stage renal disease and/or death. Cox univariable and multivariable proportional hazards models were used to examine the association between the composite endpoint and predictor variables. Survival curves were made with the use of Kaplan-Meier estimates. RESULTS: A total of 70 patients were included in the study and their median duration of follow-up was 30.4 months. Forty-eight (68.6%) patients reached the composite endpoint. The proportion reaching this endpoint at 1, 3 and 5 years were 37.5%, 64.6% and 81.3%, respectively. Cox multivariable proportional hazards model identified a serum creatinine concentration > 200 µmol/L at the time of biopsy, moderate to severe interstitial fibrosis, ≥50% crescents and cyclophosphamide therapy as predictors of the composite endpoint. CONCLUSION: Immunoglobulin-associated mesangiocapillary glomerulonephritis remains a common glomerular pathological diagnosis in our setting and has poor outcomes. This may partially be explained by late presentation. Future research needs to focus on identifying the possible cause(s) of this common glomerular disease so that more targeted therapeutic approaches can be offered.

A Narrative Review on C3 Glomerulopathy: A Rare Renal Disease.

In April 2012, a group of nephrologists organized a consensus conference in Cambridge (UK) on type II membranoproliferative glomerulonephritis and decided to use a new terminology, "C3 glomerulopathy" (C3 GP). Further knowledge on the complement system and on kidney biopsy contributed toward distinguishing this disease into three subgroups: dense deposit disease (DDD), C3 glomerulonephritis (C3 GN), and the CFHR5 nephropathy. The persistent presence of microhematuria with or without light or heavy proteinuria after an infection episode suggests the potential onset of C3 GP. These nephritides are characterized by abnormal activation of the complement alternative pathway, abnormal deposition of C3 in the glomeruli, and progression of renal damage to end-stage kidney disease. The diagnosis is based on studying the complement system, relative genetics, and kidney biopsies. The treatment gap derives from the absence of a robust understanding of their natural outcome. Therefore, a specific treatment for the different types of C3 GP has not been established. Recommendations have been obtained from case series and observational studies because no randomized clinical trials have been conducted. Current treatment is based on corticosteroids and antiproliferative drugs (cyclophosphamide, mycophenolate mofetil), monoclonal antibodies (rituximab) or complement inhibitors (eculizumab). In some cases, it is suggested to include sessions of plasma exchange.

Changes in primary glomerulonephritis in Singapore over four decades
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This review of 3,289 native kidney biopsies over the past four decades in Singapore documents the changing pattern of biopsy-proven glomerulonephritis (GN)from that of a third world country to that of a developed nation. In the 1st decade, mesangial proliferative GN was the most common form of primary GN, similar to the Asian region. In the 2nd decade, the percentage of mesangial proliferative GN decreased, but membranous GN became more common, as was seen in China and Thailand. In the 3rd decade, focal segmental glomerulosclerosis (FSGS) and membranous nephropathy continued to rise, but it was only recently, in the 4th decade, that FSGS prevalence increased dramatically, although membranous nephropathy continues to increase in some Asian countries. In the last decade in Singapore, Malaysia, and Japan, prevalence of IgA nephritis has decreased but remains the most common GN. The percentage of FSGS continues to increase in many countries like in Italy, United States of America, United Kingdom, China, and Malaysia. We surmise that socioeconomic factors play significant roles in the evolution of the renal biopsy pattern.
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C3 glomerulopathy in children: Is there still a place for anti-cellular immunosuppression?

AIM: To contribute additional clinical experience to the paucity of reports on C3 glomerulopathy (C3GP) in children, we are reporting our cohort of 11 children with C3GP, emphasizing the therapeutic options in this peculiar entity. METHODS: We describe the incidence, manifestation, histopathology findings, follow-up, treatment and outcome of C3GP in 11 children with C3GP by retrospectively analyzing their clinical charts and renal biopsy reports. RESULTS: Eleven C3GP patients were identified among 240 children who had undergone renal biopsy, accounting for a 4.6% incidence of C3GP. A light microscopy examination showed a membranoproliferative pattern (n = 8), mesangial proliferation (n = 1), a mesangial/membranoproliferative pattern (n = 1) and endocapillary proliferation (n = 1). All children presented with proteinuria of varying degrees, the majority of them with additional hematuria, three with full-blown nephrotic-nephritic syndrome, and two with renal insufficiency at presentation. Very diverse treatments were applied in our cohort of patients, from no specific treatment to different mono or combined anti-cellular immunosuppression treatments, as well as a trial of plasma therapy or eculizumab. Our results are in to some extend in concordance with other studies revealing that an optimal therapy for C3GP is still unknown, but we believe that a trial of classical immunosuppression before eculizumab is still worth trying, while eculizumab can have a beneficial effect, but not in all patients. CONCLUSION: A diverse histological pattern and clinical picture and no known optimal therapy are a hallmark of C3GP.

Long-term outcomes of patients with end-stage kidney disease due to membranoproliferative glomerulonephritis: an ANZDATA registry study.

BACKGROUND: Membranoproliferative glomerulonephritis (MPGN) is an uncommon cause of end stage kidney disease (ESKD) and the clinical outcomes of patients with MPGN who commence kidney replacement therapy have not been comprehensively studied. METHODS: All adult patients with ESKD due to glomerulonephritis commencing kidney replacement therapy in Australia and New Zealand from January 1, 1996 to December 31, 2016 were reviewed. Patients with ESKD due to MPGN were compared to patients with other forms of glomerulonephritis. Patient survival on dialysis and following kidney transplantation, kidney recovery on dialysis, time to transplantation, allograft survival, death-censored allograft survival and disease recurrence post-transplant were compared between the two groups using Kaplan Meier survival curves and Cox proportional hazards regression. RESULTS: Of 56,481 patients included, 456 (0.8%) had MPGN and 12,660 (22.4%) had another form of glomerulonephritis. Five-year patient survival on dialysis and following kidney transplantation were similar between patients with ESKD from MPGN and other forms of glomerulonephritis (Dialysis: 59% vs. 62% p = 0.61; Transplant: 93% vs. 93%, p = 0.49). Compared to patients with other forms of glomerulonephritis, patients with MPGN had significantly poorer 5-year allograft survival (70% vs. 81% respectively, p = 0.02) and death censored allograft survival (74% vs. 87%, respectively; p < 0.01). The risk of disease recurrence was significantly higher in patients with MPGN compared to patients with other glomerulonephritidites (18% vs. 5%; p < 0.01). In patients with MPGN who had allograft loss, patients with MPGN recurrence had a significantly shorter time to allograft loss compared to patients with MPGN who had allograft loss due to any other cause (median time to allograft loss 3.2 years vs. 4.4 years, p < 0.01). CONCLUSIONS: Compared with other forms of glomerulonephritis, patients with MPGN experienced comparable rates of survival on dialysis and following kidney transplantation, but significantly higher rates of allograft loss due to disease recurrence.

C3 glomerulonephritis and dense deposit disease share a similar disease course in a large United States cohort of patients with C3 glomerulopathy.

C3 glomerulonephritis (C3GN) and dense deposit disease comprise the two classes of C3 glomerulopathy. Studies from Europe and Asia have aided our understanding of this recently defined disorder, but whether these data apply to a diverse United States patient population remains unclear. We, therefore, reviewed clinical and histopathological data, including generation of a C3 Glomerulopathy Histologic Index to score biopsy activity and chronicity, to determine predictors of progression to end-stage renal disease (ESRD) and advanced chronic kidney disease (CKD) in 111 patients (approximately 35% non-white) with C3 glomerulopathy: 87 with C3GN and 24 with dense deposit disease. Complement-associated gene variants and autoantibodies were detected in 24% and 35% of screened patients, respectively. Our C3 Glomerulopathy Histologic Index denoted higher activity in patients with C3GN and higher chronicity in patients with dense deposit disease. Over an average of 72 months of follow-up, remission occurred in 38% of patients with C3GN and 25% of patients with dense deposit disease. Progression to late-stage CKD and ESRD was common, with no differences between C3GN (39%) and dense deposit disease (42%). In multivariable models, the strongest predictors for progression were estimated glomerular filtration rate at diagnosis (clinical variables model) and tubular atrophy/interstitial fibrosis (histopathology variables model). Using our C3 Glomerulopathy Histologic Index, both total activity and total chronicity scores emerged as the strongest predictors of progression. Thus, in a large, diverse American cohort of patients with C3 glomerulopathy, there is a high rate of progression to CKD and ESRD with no differences between C3GN and dense deposit disease.

The Phenotypic Spectrum of Nephropathies Associated with Mutations in Diacylglycerol Kinase ε.

The recent discovery of mutations in the gene encoding diacylglycerol kinase ε (DGKE) identified a novel pathophysiologic mechanism leading to HUS and/or MPGN. We report ten new patients from eight unrelated kindreds with DGKE nephropathy. We combined these cases with all previously published cases to characterize the phenotypic spectrum and outcomes of this new disease entity. Most patients presented with HUS accompanied by proteinuria, whereas a subset of patients exhibited clinical and histologic patterns of MPGN without TMA. We also report the first two patients with clinical and histologic HUS/MPGN overlap. DGKE-HUS typically manifested in the first year of life but was not exclusively limited to infancy, and viral triggers frequently preceded HUS episodes. We observed signs of complement activation in some patients with DGKE-HUS, but the role of complement activation remains unclear. Most patients developed a slowly progressive proteinuric nephropathy: 80% of patients did not have ESRD within 10 years of diagnosis. Many patients experienced HUS remission without specific treatment, and a few patients experienced HUS recurrence despite complete suppression of the complement pathway. Five patients received renal allografts, with no post-transplant recurrence reported. In conclusion, we did not observe a clear genotype-phenotype correlation in patients with DGKE nephropathy, suggesting additional factors mediating phenotypic heterogeneity. Furthermore, the benefits of anti-complement therapy are questionable but renal transplant may be a feasible option in the treatment of patients with this condition.

Short-term outcome of clinical and histopathologic variants of mesangiocapillary glomerulonephritis in children: A retrospective analysis from a tertiary care center.

OBJECTIVE: To study the frequency, clinicopathological features and short-term outcome of mesangiocapillary glomerulonephritis (MCGN) in children at a tertiary care kidney center in Pakistan. METHODS: A descriptive, observational study was conducted at the Paediatric Nephrology Department, Sindh Institute of Urology and Transplantation, Karachi, from January 2011 till December 2015. A review of all paediatric (<18 years) renal biopsies during the study period was performed and cases of MCGN were enrolled. The clinical presentation, laboratory findings, histology and outcome were analyzed. RESULTS: During the study period, 890 paediatric renal biopsies were performed. Of these, 63(7%) were MCGN. Among these, 34(54%) were males and 29 (46%) females. Mean age was 9.9 ± 3.2years. Thirty four (54%) presented with nephrotic syndrome (NS), and29 (46%) with rapidly progressive glomerulonephritis (RPGN).Mean duration of follow-up was 1.66 ± 1.34 years. Outcome of patients with NS with renal failure (RF)was complete remission (CR) in 1(7.7%), persistent proteinuria with normal renal functions in 1(7.7%),chronic kidney disease (CKD) in 3 (23%), end-stage renal disease (ESRD) in 4 (30.8%), while 4 (30.8%) children died, while in children with NS and normal renal functions, CR was obtained in 3(14.2%), partial remission (PR) in 10(47.6%),CKD in 4(19%), and ESRD in 3 (14.3%).Outcome of cases presenting as RPGN was CR in 13 (44.8%), CKD in 2(6.9%) and ESRD in 7(24.1%) cases. Four children (13.8%) were lost to follow-up, while 3(10.3%) died. CONCLUSIONS: Children with MCGN presenting clinically with NS with impaired renal functions have worst outcome.

Patterns of renal disease in South Korea: a 20-year review of a single-center renal biopsy database.

BACKGROUND: Several registries and centers have reported the results of renal biopsies from different parts of the world. As there are few data regarding the epidemiology of glomerulonephritis (GN) in South Korea, we conducted this study on renal biopsy findings during the last 20 years from a single center. METHODS: Data for 818 patients who underwent renal biopsy at our center between 1992 and 2011 were collected retrospectively. All kidney specimens were examined with light microscopy (LM) and immunofluorescent microscopy (IF). RESULTS: There were 818 cases of native kidney biopsies. In cases of primary GN, the most frequent type of renal pathology in adults (18-59 years) was mesangial proliferative GN (MsPGN, 34.5%) followed by IgA nephropathy (IgAN, 33.3%) and membranous GN (MGN, 8.8%). Indications in adults (18-59 years) were asymptomatic urinary abnormalities (75.3%) followed by nephrotic syndrome (19.8%) and acute kidney injury (AKI, 3.4%). CONCLUSIONS: Among 818 renal biopsy specimens, MsPGN and IgAN were the most frequent biopsy-proven renal diseases. MGN was the third most common cause of primary GN and lupus nephritis (LN) was the most common secondary glomerular disease. Our data contribute to the epidemiology of renal disease in South Korea.

Differences in clinical findings, pathology, and outcomes between C3 glomerulonephritis and membranoproliferative glomerulonephritis.

BACKGROUND: To clarify the clinical manifestations of pediatric complement component C3 glomerulonephritis (C3GN), we retrospectively evaluated differences in the clinicopathological findings and prognosis between C3GN and immune-complex-mediated membranoproliferative glomerulonephritis (IC-MPGN). METHODS: Thirty-seven patients diagnosed with "idiopathic MPGN" were enrolled in this retrospective study. The patients were divided into two groups, with Group 1 consisting of 19 patients diagnosed with IC-MPGN and Group 2 consisting of 18 patients diagnosed with C3GN. The clinical findings and the prognosis were investigated for both groups. RESULTS: Thirteen patients in Group 2 were identified by mandatory annual school screening for urinary abnormalities. The incidence of macro-hematuria and the frequency of low serum C4 values were lower in Group 2 patients than in Group 1 patients. At the time of the second renal biopsy, urinary protein excretion, incidence of hematuria, frequency of low serum C3 values, and scores for mesangial proliferation, glomerular sclerosis, and interstitial fibrosis were higher in Group 2 patients than in Group 1 patients. At the most recent follow-up examination, the number of patients categorized as non-responding or with end-stage renal disease was higher in Group 2 patients than in Group 1 patients. CONCLUSIONS: Our results suggest that the treatment response and prognosis of patients with C3GN are worse than those of patients with IC-mediated MPGN. Therefore, in the clinical context regarding treatment options and prognosis, it may be useful to classify idiopathic MPGN as C3GN or IC-MPGN. In addition, long-term follow-up of C3GN is necessary.

The changing pattern of glomerular disease in HIV and hepatitis C co-infected patients in the era of HAART.

Previous reports have suggested a poor renal prognosis in patients with HIV and HCV co-infection with a preponderance of immune complex mediated glomerular disease on biopsy. Although the benefits of HAART on HIVAN are known, its impact on co-infected patients is unclear. We describe the renal biopsy findings and renal outcome in 29 co-infected patients in the HAART era and compare them to findings in 14 historical controls reported from our institution in the pre-HAART era. Our present cohort was predominantly male and Black with the majority reporting a history of intravenous (i.v.) drug use. Renal biopsy findings included 16 patients with immune complex mediated glomerular disease and 14 patients with FSGS, of which only 3 had collapsing features and/or tubular microcysts typical of HIVAN. Five patients had other biopsy diagnoses not directly related to viral infection. Median renal survival in our cohort was 15.6 months - significantly better than the 1.7 months seen our pre-HAART cohort. The modern cohort's improved renal outcome occurred despite older patients, longer HIV infection and similar levels of renal insufficiency. Our data indicate a changing epidemiology and natural history of renal disease in the HAART era with less immune complex mediated glomerular disease and more non-collapsing FSGS of the usual type. The marked improvement is likely to be multifactorial, including use of antiretroviral and anti-HCV therapies, RAAS antagonists, earlier nephrology referral and generally improved medical care.

Primary membranoproliferative glomerulonephritis on the decline: decreased rate from the 1970s to the 2000s in Japan.

BACKGROUND: A prolonged change in the rate of primary membranoproliferative glomerulonephritis (MPGN) was identified using a Japanese database of renal biopsies. METHODS: We retrospectively investigated 6,369 renal biopsies that were performed between 1976 and 2009. Primary MPGN patients were selected, and the clinical and pathological findings were examined. We also statistically analyzed the changing rate of the onset of primary MPGN according to each decade. RESULTS: Seventy-nine cases with primary MPGN (1.2 % of total biopsies) were diagnosed. The age of the patients ranged from 6-79 years (average 34.6 years). There were 24 children and 55 adults, including 37 male and 42 female patients. Thirty-six cases of primary MPGN (45.6 %) showed nephrotic syndrome-8 childhood and 28 adult cases. In the pathological classification of 44 samples using electron microscopy, 29 cases were MPGN type I, 1 case was MPGN type II, and 14 cases were MPGN type III. The secular change of the rate of primary MPGN onset showed a statistically significant reduction from the 1970s to the 2000s. The rate of primary MPGN onset in the child population also significantly decreased, but not in the adult population. Among the clinical parameters, disease severity and prognosis remained unchanged. Regarding treatment in recent years, steroid pulse therapy became more available but the administration of warfarin and anti-platelet drugs significantly decreased. CONCLUSION: We concluded that the rate of total primary MPGN and that of pediatric patients with primary MPGN decreased.

Acute presentation and persistent glomerulonephritis following streptococcal infection in a patient with heterozygous complement factor H-related protein 5 deficiency.

Acute poststreptococcal glomerulonephritis is a common cause of acute nephritis in children. Transient hypocomplementemia and complete recovery are typical, with only a minority developing chronic disease. We describe a young girl who developed persistent kidney disease and hypocomplementemia after a streptococcal throat infection. Kidney biopsy 1 year after presentation showed isolated glomerular complement C3 deposition, membranoproliferative changes, and subendothelial, intramembranous and occasional subepithelial electron-dense deposits consistent with C3 glomerulopathy. Complement gene screening revealed a heterozygous single nucleotide insertion in exon 4 of the complement factor H-related protein 5 gene (CFHR5), resulting in a premature stop codon. This variant was not detected in 198 controls. Serum CFHR5 levels were reduced. The mother and sister of the index patient were heterozygous for the sequence variant, with no overt evidence of kidney disease. We speculate that this heterozygous CFHR5 sequence variant is a risk factor for the development of chronic kidney disease after streptococcal infection.

Trends in pediatric primary membranoproliferative glomerulonephritis costs and complications.

BACKGROUND: Data on pediatric membranoproliferative glomerulonephritis (MPGN) epidemiology, complications, and healthcare costs are critical to our understanding of MPGN's economic burden and of how best to direct clinical care and research efforts in the future. METHODS: We analyzed 10-year trends in epidemiology, complications, and hospital charges for pediatric primary MPGN hospitalizations using the Healthcare Cost and Utilization Project (HCUP) Kids' Inpatient Database (KID) for 1997-2006. We identified approximately 320 primary MPGN admissions per year, corresponding to approximately 4.3 % of all glomerular disease admissions. RESULTS: Older children were at higher risk for admission (odds ratios for ages 6-10, 11-15, and 16-18 years were 7.5, 9.3, and 4.7, respectively compared to 0-5 years; p < 0.0001). Gender, race, income, hospital location, and admission season were not significant risk factors. The incidence of MPGN admission-associated acute renal failure (ARF) increased to >147 % (from <3 to 7.4 %) over time, while admission-associated renal biopsy (approx. 34.8 %), renal replacement therapy (approx. 18.4 %), and transplantation (approx. 5 %) remained constant. Hospital length of stay (LOS) increased by 68 % (from 5.0 to 8.4 days), whereas mean total hospital charges increased by 213 % (from $13,718 to $42,891), concomitant with a strong trend from private toward public health insurance. CONCLUSIONS: We conclude that while the incidence of pediatric primary MPGN hospitalizations has remained stable over the last 10 years, they have been associated with marked increases in the frequency of ARF, as well as dramatically increased hospital LOS and charges.

The increasing incidence of initial steroid resistance in childhood nephrotic syndrome.

BACKGROUND: Recently, a number of reports have highlighted changes in the histopathology and response to corticosteroid treatment in childhood nephrotic syndrome; however, these involved ethnically mixed populations. For comparison, the purpose of our research was to search for changes in the characteristics of nephrotic syndrome in a homogeneous population of Caucasian children over two consecutive decades. METHODS: Chart analysis was performed to identify children with new-onset nephrotic syndrome. The children were admitted to the Division of Pediatric Nephrology, Zabrze, during two periods: 1986-1995 (76 patients) and 1996-2005 (102 patients). Specifically, a comparison of clinical characteristics and morphology of nephrotic syndrome between the two groups was performed. Steroid resistance was defined as no remission within 8 weeks of corticosteroid treatment. Histopathology was available in 36.8% and 43.1% of patients respectively. RESULTS: There was a significant increase in primary steroid resistance in the latter decade: 15.8% vs 31.4% (P = 0.017). Changes in the histopathology did not reach the level of statistical significance: minimal change nephrotic syndrome 25% vs 9% (P = 0.095), mesangial proliferative glomerulonephritis 46.4% vs 61.3% (P = 0.21), focal segmental glomerulosclerosis 17.9% vs 20.4% (P = 0.78), membranoproliferative glomerulonephritis 7.1% vs 6.8% (P = 1.0), membranous glomerulonephritis 3.6% vs 0% (P = 0.39). CONCLUSIONS: Our results show the increasing incidence of primary steroid resistance in childhood nephrotic syndrome.

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.