Incidence and prognostic importance of glomerular crescents in renal diseases of childhood

Crescents in Kidney Biopsy - What Do They Imply? A Clinicopathologic Study of 40 Cases in a Tertiary Care Center

Introduction:

Crescents in glomeruli mean proliferation of parietal epithelium of Bowman's capsule with the presence of macrophages, lymphocytes, neutrophils, fibrin, and collagen. When crescents are present in >50% of nonfibrosed glomeruli, it is called crescentic glomerulonephritis (CGN). The presence of crescents is indicative of poorer prognosis. CGN can be pauci immune (PI), immune complex mediated (ICM), and anti-glomerular basement membrane (anti-GBM) disease.

Aim:

The aim was to study the clinicopathological spectrum of CGN over a period of 10 years in our center.

Materials and Methods:

Forty kidney biopsies with the presence of crescents over a period of 5 years were retrieved retrospectively from the histopathology records of the department of pathology. The clinical history, laboratory parameters, histopathology report, and the direct immunofluorescence (DIF) findings were analyzed.

Results:

Totally 40 cases had crescents on light microscopy. Out of these, 17 cases qualified for CGN. The mean age of the patients was 20 years. Nephritic syndrome was the most common presentation in these 17 cases. The mean creatinine level was 3.55 mg/dL. PI (7/17, 41.1%) was the most common category, followed by ICM (6/17, 35.2%) and anti-GBM (4/17, 23.5%). Out of the ICM, two cases were of IgA nephropathy with crescents and one of lupus with crescents.

Conclusion:

PI is the most common type of CGN. DIF examination is essential for exact categorization of CGN. Kidney biopsy in these cases can guide management and benefit patients with timely initiation of aggressive therapy.

Renal Survival in Children with Glomerulonephritis with Crescents: A Pediatric Nephrology Research Consortium Cohort Study

There is no evidence-based definition for diagnosing crescentic glomerulonephritis. The prognostic implications of crescentic lesions on kidney biopsy have not been quantified. Our objective was to determine risk factors for end-stage kidney disease (ESKD) in patients with glomerulonephritis and crescents on kidney biopsy. A query of the Pediatric Nephrology Research Consortium’s Pediatric Glomerulonephritis with Crescents registry identified 305 patients from 15 centers. A retrospective cohort study was performed with ESKD as the primary outcome. Median age at biopsy was 11 years (range 1–21). The percentage of crescents was 3–100% (median 20%). Etiologies included IgA nephropathy (23%), lupus (21%), IgA vasculitis (19%) and ANCA-associated GN (13%), post-infectious GN (5%), and anti-glomerular basement membrane disease (3%). The prevalence of ESKD was 12% at one year and 16% at last follow-up (median = 3 years, range 1–11). Median time to ESKD was 100 days. Risk factors for ESKD included %crescents, presence of fibrous crescents, estimated GFR, and hypertension at biopsy. For each 1% increase in %crescents, there was a 3% decrease in log odds of 1-year renal survival (p = 0.003) and a 2% decrease in log odds of renal survival at last follow-up (p < 0.001). These findings provide an evidence base for enrollment criteria for crescentic glomerulonephritis in future clinical trials.

Crescent lesions are not a predictive factor in adult-onset Henoch-Schönlein purpura nephritis

Henoch-Schönlein purpura nephritis (HSPN) is a common secondary glomerulonephritis, and its prognosis mainly depends on the severity of renal impairment. To date, the significance of crescent lesions in adult-onset HSPN is still unclear. Therefore, the purpose of this research was to assess whether crescents could predict the renal outcomes in adult HSPN patients. A total of 188 adult patients with HSPN proven by renal biopsy were enrolled in this prospective study. Patients were divided into three groups based on the proportion of crescents: non-crescent group (C0, n = 110), crescent ≤ 25% group (C1, n = 50) and crescent > 25% group (C2, n = 28). The composited endpoint was defined as eGFR decreased > 50% of baseline level, reached end-stage renal disease and/or death. Among three groups, clinical pathological features, treatment regimens and renal outcomes were compared. During a mean follow-up of 26 months, 78 (42.5%) patients had crescent lesions. A total of ten (9.1%) patients in C0 group and five (17.9%) patients in C2 group reached the combined endpoint, but no patients in C1 group reached endpoint. Renal survival analysis indicated patients in C1 group tended to have the best renal outcome, while patients in C2 group had the poorest renal survival. Moreover, Cox regression analysis revealed crescents were not a predictor of poor developing to renal outcome after adjusting potential confounders [hazard ratio (HR) = 0.28, 95% confidence interval (CI) 0.07-1.18, P = 0.083]. Crescent formation is not necessarily a predictive factor of poor renal survival in adult HSPN patients who had small proportions of crescents (crescent ≤ 25%).

Dense deposit disease and C3 glomerulopathy

C3 glomerulopathy refers to those renal lesions characterized histologically by predominant C3 accumulation within the glomerulus, and pathogenetically by aberrant regulation of the alternative pathway of complement. Dense deposit disease is distinguished from other forms of C3 glomerulopathy by its characteristic appearance on electron microscopy. The extent to which dense deposit disease also differs from other forms of C3 glomerulopathy in terms of clinical features, natural history, and outcomes of treatment including renal transplantation is less clear. We discuss the pathophysiology of C3 glomerulopathy, with evidence for alternative pathway dysregulation obtained from affected individuals and complement factor H (Cfh)-deficient animal models. Recent linkage studies in familial C3 glomerulopathy have shown genomic rearrangements in the Cfh-related genes, for which the novel pathophysiologic concept of Cfh deregulation has been proposed.

Ethylmalonic encephalopathy associated with crescentic glomerulonephritis

Ethylmalonic encephalopathy (EE) is a rare autosomal recessive disorder caused by mutations in the ETHE1 gene and characterized by chronic diarrhea, encephalopathy, relapsing petechiae and acrocyanosis. Nephrotic syndrome has been described in an infant with EE but the renal histology findings were not described in previous reports. We report a Palestinian girl with EE who presented with chronic diarrhea, encephalopathy, petechial rash and acrocyanosis. Subsequently, she developed progressive deterioration of renal function caused by rapidly progressive glomerulonephritis resulting in death within few days. This is, to our knowledge, the first reported occurrence of rapidly progressive glomerulonephritis in a child with ethylmalonic encephalopathy. Its presence is a serious complication associated with poor prognosis and may be explained by the diffuse vascular damage.

Etiology and outcome of crescentic glomerulonephritis

OBJECTIVE

To determine the etiology, course and predictors of outcome in children with crescentic glomerulonephritis (GN).

STUDY DESIGN

Retrospective, descriptive study.

SETTING

Pediatric Nephrology Clinic at a referral center in Northern India.

METHODS

Clinic records of patients aged <18 year with crescentic GN diagnosed from 2001 - 2010 and followed at least 12 months were reviewed. Crescentic GN, defined as crescents in ≥50% glomeruli, was classified based on immunofluorescence findings and serology. Risk factors for renal loss (chronic kidney disease stage 4-5) were determined.

RESULTS

Of 36 patients, (median age 10 yr) 17 had immune complex GN and 19 had pauci-immune crescentic GN. The etiologies of the former were lupus nephritis (n=4), postinfectious GN (3), and IgA nephropathy, Henoch Schonlein purpura and membranoproliferative GN type II (2 each). Three patients with pauciimmune GN showed antineutrophil cytoplasmic antibodies (ANCA). Rapidly progressive GN was present in 33 patients, and required dialysis in 12. At median 34 (19-72) months, 2 patients with immune complex GN and 8 with pauciimmune GN showed renal loss. Renal survival was 94.1% at 3 yr, and 75.3% at 8 yr in immune complex GN; in pauciimmune GN survival was 63.2% and 54.1%, respectively (P=0.054). Risk factors for renal loss were oliguria at presentation (hazards ratio, HR 10.50; P=0.037) and need for dialysis (HR 6.33; P=0.024); there was inverse association with proportion of normal glomeruli (HR 0.91; P=0.042).

CONCLUSIONS

Pauci-immune GN constitutes one-half of patients with crescentic GN at this center. Patients with pauciimmune GN, chiefly ANCA negative, show higher risk of disease progression. Renal loss is related to severity of initial presentation and extent of glomerular involvement.

Clinical spectrum and outcome of crescentic glomerulonephritis in children in developing countries

Crescentic glomerulonephritis (CsGN) is an uncommon entity in children. This prospective study was conducted to evaluate the aetiology, clinical spectrum and outcome in children with crescentic glomerulonephritis. The single-centre prospective study comprised of 22 children with biopsy proven CsGN who had been referred to our institute over the period January 2000 to December 2005. These patients were subjected to detailed clinical and biochemical examinations. The diagnosis of underlying renal disease was based on various criteria, including the clinical picture, serology and histopathology. The patients received intravenous methyl prednisolone, oral steroid treatment, and oral cyclophosphamide with or without plasmapheresis. All patients received supportive care, including control of hypertension and oedema and supportive management of renal insufficiency. During this 5-year period, CsGN accounted for 5.1% of all biopsies done in children. The mean age was 12.27 years (range 4 years to 18 years). There were eight girls and 14 boys. The mean duration of symptoms prior to referral was 2.47 months (range 5 days to 21 months). Aetiology was immune complex in 19 cases, anti-glomerular basement membrane (anti-GBM) antibody disease in two cases and pauci-immune (Wegener's granulomatosis) in one case. The percentage of crescents ranged from 50% to 100% (mean 70.6%). Twenty-one out of 22 (95.5%) children in our series had hypertension at presentation that required treatment with antihypertensive medications. The serum creatinine level at presentation ranged from 1.5 mg/dl to 11.4 mg/dl (mean 5.5 mg/dl). Of the 22 children, two were lost to follow-up, while the mean follow-up period of the rest of the 20 children was 8.13 months (range 1 month to 43 months). At the last follow-up of the 22 children, ten had stage 5 chronic kidney disease (CKD) and three had stage 4 CKD, while seven children had a calculated glomerular filtration rate (GFR) of >60 ml/min per 1.73 m(2) body surface area. Persistent proteinuria was seen on follow-up in the majority [13/20 (65%)] of patients. The outcome of CsGN in children continues to be poor, in our experience, due to delayed referral and delayed diagnosis. This was correlated histologically by the presence of fibrocellular crescents in the majority of our patient. Thus CsGN should be treated as a renal emergency. A greater awareness of this disease needs to be created amongst the referring paediatricians in developing countries to facilitate early diagnosis and prompt treatment.

Dense deposit disease is not a membranoproliferative glomerulonephritis

Dense deposit disease (first reported in 1962) was classified as subtype II of membranoproliferative glomerulonephritis in the early 1970s. Over the last 30 years, marked differences in etiology and pathogenesis between type I membranoproliferative glomerulonephritis and dense deposit disease have become apparent. The sporadic observation that dense deposit disease can be seen with markedly different light microscopy appearances prompted this study. The goal was to examine a large number of renal biopsies from around the world to characterize the histopathologic features of dense deposit disease. Eighty-one cases of dense deposit disease were received from centers across North America, Europe and Japan. Biopsy reports, light microscopy materials and electron photomicrographs were reviewed and histopathologic features scored. Sixty-nine cases were acceptable for review. Five patterns were seen: (1) membranoproliferative n=17; (2) mesangial proliferative n=30; (3) crescentic n=12; (4) acute proliferative and exudative n=8 and (5) unclassified n=2. The age range was 3-67 years, with 74% in the range of 3-20 years; 15% 21-30 years and 11% over 30 years. Males accounted for 54% and females 46%. All patients with either crescentic dense deposit disease or acute proliferative dense deposit disease were between the ages of 3 and 18 years. The essential diagnostic feature of dense deposit disease is not the membranoproliferative pattern but the presence of electron dense transformation of the glomerular basement membranes. Based upon this study and the extensive data developed over the past 30 years, dense deposit disease is clinically distinct from membranoproliferative glomerulonephritis and is morphologically heterogeneous with only a minority of cases having a membranoproliferative pattern. Therefore, dense deposit disease should no longer be regarded as a subtype of membranoproliferative glomerulonephritis.

Mesangiocapillary glomerulonephritis type II (dense-deposit disease): clinical features of progressive disease

Twenty-seven patients presenting to the Royal Melbourne Hospital between 1968 and 1988 with mesangiocapillary glomerulonephritis type II with intramembranous dense deposits (dense-deposit disease, DDD) are analyzed. Patients were divided into two groups on the basis of whether renal function deteriorated (14 patients) or remained stable (13 patients). At presentation or during the course of the disease, heavy proteinuria, macroscopic hematuria, and high quantitative urinary red cell or white cell counts characterized patients with progressive disease. Patients with crescents on their initial renal biopsy or with large numbers of polymorphs in glomerular capillaries corresponding with sterile pyuria were more likely to have deterioration of renal function. The average time from onset of symptoms to development of end-stage renal disease was over 16 years. The patient's clinical course could not be anticipated by serum complement profiles, the presence of C3 nephritic factor, or partial lipodystrophy. Pregnancy did not affect the course of the disease. Six patients underwent renal transplantation and the disease recurred on renal biopsy in four. However, only two individuals lost renal allografts due to recurrent DDD.

Glomerular diseases in children. "The Iranian experience"

A total of 411 children, aged from 0.3 to 18 years, suffering from glomerular diseases, were studied by renal biopsy between 1976 and 1985. The clinical presentation included nephrotic syndrome (79% of cases), renal failure (43%), and arterial hypertension (38%). In all, 177 cases presented with primary nephrotic syndrome; all had complicated courses and most were either corticosteroid-dependent or -resistant. Only 26.6% had minimal change disease on renal biopsy; 56.5% had focal-segmental sclerosis; and immunofluorescent deposits were observed in half of the group. Acute poststreptococcal (36 cases), mesangiocapillary (80 cases), and lupus (34 cases) glomerulonephritis occurred frequently; IgA glomerulopathy (10 cases) and haemolytic uraemic syndrome (6 cases) were uncommon. Glomerular crescents were observed in 71 cases. These observations illustrate the types of glomerular diseases seen in Iranian children.