Crescentic glomerulonephritis due to linear IgA anti-glomerular basement membrane disease: report of a rare case.

Anti-glomerular basement membrane (GBM) disease is a rare and severe vasculitis that affects the glomerular and pulmonary capillaries and has an incidence of less than 2 cases per million individuals per year. Anti-GBM disease is mediated by autoantibodies against the α3 chain of type IV collagen. In the majority of cases, the autoantibodies are of the immunoglobulin G (IgG) class, with rare cases being mediated by immunoglobulin M (IgM) or immunoglobulin A (IgA); there are less than 15 IgA-mediated cases reported in the literature worldwide. The classic form of this disease manifests with rapidly progressive glomerulonephritis (RPGN), with or without pulmonary hemorrhage, and the diagnosis consists of identifying high titers of autoantibodies in the serum and/or deposited in the tissues. IgA antibodies are not identified in routine immunoassay tests, and renal biopsy with immunofluorescence is essential for diagnosis. We present a case of RPGN due to anti-GBM disease with linear IgA deposition, whose diagnosis was made exclusively by renal biopsy and with an unfavorable prognosis.

Association of neutrophil extracellular trap levels with Raynaud's phenomenon, glomerulonephritis and disease index score in SLE patients from Brazil.

Neutrophil extracellular traps (NETs) are cell-extruded DNA strands coated with neutrophils' nuclear proteins and enzymes from cytotoxic granules, produced by NETosis, a cell death pathway. They perform an important defensive role in innate immunity, but their increased production and/or inefficient degradation expose new antigens, such as DNA or citrullinated histone peptides, triggering autoimmunity. This study aimed to access possible associations between serum NETs levels with epidemiological, clinical, and serological data from a well-characterized SLE Brazilian patients' cohort. NET levels were evaluated in one hundred seventy serum samples of patients with Systemic Lupus Erythematosus (SLE) using an Immunoassay. Univariate and multivariate binary logistic regression used clinical patients' data as independent variables. Parametric and non-parametric tests compared log10 base serum NET levels transformed between patients' groups. SLE patients were also dichotomized into "High serum NET levels" and "Low serum NET levels" groups. All analyses were performed in R language 4.1.2, and p < 0.05 were considered significant. Increased susceptibility for high serum NET levels was observed in SLE patients with Raynaud's phenomenon (OR = 2.30, 95 % CI = 1.06-5.21 and p = 0.039), independently of any other risk factor. Also, SLE patients with Raynaud's phenomenon presented higher mean NET serum levels (mean = -0.13 vs. -0.51, p = 0.01). In addition, higher mean NET serum levels were associated with glomerulonephritis (mean = -0.45 vs. -0.12, p = 0.03). Ultimately, the SLEDAI index scored higher in the high NETs serum levels group (median = 2.0 vs. 0.0, p = 6 × 10-3). The formation of NETs might be implicated in Raynaud's phenomenon, glomerulonephritis, and disease index score in SLE patients. Our results highlight the importance of serum NET levels as a possible therapeutical target to modulate the clinical course of SLE.

Angiotensin II and post-streptococcal glomerulonephritis.

BACKGROUND: Post-streptococcal glomerulonephritis (PSGN) is a consequence of the infection by group A beta-hemolytic streptococcus. During this infection, various immunological processes generated by streptococcal antigens are triggered, such as the induction of antibodies and immune complexes. This activation of the immune system involves both innate and acquired immunity. The immunological events that occur at the renal level lead to kidney damage with chronic renal failure as well as resolution of the pathological process (in most cases). Angiotensin II (Ang II) is a molecule with vasopressor and pro-inflammatory capacities, being an important factor in various inflammatory processes. During PSGN some events are defined that make Ang II conceivable as a molecule involved in the inflammatory processes during the disease. CONCLUSION: This review is focused on defining which reported events would be related to the presence of this hormone in PSGN.

Renal Morphology in Coronavirus Disease: A Literature Review.

Renal biopsy is useful to better understand the histological pattern of a lesion (glomerular, tubulointerstitial, and vascular) and the pathogenesis that leads to kidney failure. The potential impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on the kidneys is still undetermined, and a variety of lesions are seen in the kidney tissue of coronavirus disease patients. This review is based on the morphological findings of patients described in case reports and a series of published cases. A search was conducted on MEDLINE and PubMed of case reports and case series of lesions in the presence of non-critical infection by SARS-CoV-2 published until 15/09/2020. We highlight the potential of the virus directly influencing the damage or the innate and adaptive immune response activating cytokine and procoagulant cascades, in addition to the genetic component triggering glomerular diseases, mainly collapsing focal segmental glomerulosclerosis, tubulointerstitial, and even vascular diseases. Kidney lesions caused by SARS-CoV-2 are frequent and have an impact on morbidity and mortality; thus, studies are needed to assess the morphological kidney changes and their mechanisms and may help define their spectrum and immediate or long-term impact.

Autoimmunity in Acute Poststreptococcal GN: A Neglected Aspect of the Disease.

Acute poststreptococcal GN (APSGN) is the prototype of immune complex GN and is associated with manifestations of autoimmune reactivity that have been neglected as epiphenomena. Recently, studies have demonstrated transient antifactor B autoantibodies that activate the alternative complement pathway, bringing self-immunity to a central position in the pathogenesis of APSGN. Therefore, examining other manifestations of autoimmunity that have been reported in association with poststreptococcal GN is of interest. This article reviews the renal and extrarenal manifestations of autoimmune reactivity in APSGN and considers their potential relevance in modifying the usually benign clinical course of the disease. It also discusses related aspects of the nephritogenic antigens, complement activation, and genetic elements associated with immune reactivity and their potential relevance to the familial incidence of the disease.

Non-lupus full house nephropathy in pediatrics: Case reports / Nefropatía full house no lúpica en pediatría: reporte de dos casos.

Full house nephropathy is defined as the simultaneous detection of IgA, IgG, IgM, C3, and C1q deposits by immunofluorescence, usually indicating lupus nephritis. There are patients with this immunofluorescence pattern, but with negative autoantibody serology, which means they cannot be diagnosed with systemic lupus erythematosus. Patients presenting with full house nephropathy but no other criteria for lupus are diagnosed as having nonlupus full house nephropathy. Here, we describe two cases: A male patient who debuted with rapidly progressive glomerulonephritis and a female patient with nephrotic syndrome. Both had negative autoantibody serology, findings in the renal biopsy of class IV lupus nephritis and afull house immunofluorescence pattern. Histological findings in non-lupus full house nephropathy are similar to those in lupus nephritis and, probably, similar physiopathological bases. However, prospective studies are needed to determine risk factors and the renal prognosis and to make suggestions for specific treatments.

La nefropatía full house se refiere a la detección simultánea de depósitos de IgA, IgG, IgM, C3 y C1q en la inmunofluorescencia, lo que generalmente indica la presencia de nefritis lúpica. Hay pacientes con este patrón de inmunofluorescencia, pero con serología negativa para autoanticuerpos, por lo que no se les puede diagnosticar un lupus eritematoso sistémico. Este tipo de nefropatía, en la que no se presentan otros criterios para lupus, se denomina nefropatía full house no lúpica. En esta presentación, se describen dos casos: un paciente que ingresó con una glomerulonefritis rápidamente progresiva y una paciente con síndrome nefrótico, ambos con serología negativa para autoanticuerpos, hallazgos en la biopsia renal indicativos de nefritis lúpica de clase IV y un patrón full house en la inmunofluorescencia. La nefropatía full house no lúpica tiene rasgos histológicos similares a los de la nefritis lúpica y, probablemente, sus bases fisiopatológicas son parecidas. Sin embargo, se necesitan estudios prospectivos para conocer los factores de riesgo y el pronóstico renal, y poder hacer sugerencias sobre tratamientos específicos.

Anca negative pauci-immune crescentic glomerulonephritis and mixed connective tissue disease: a case study / Glomerulonefrite crescêntica pauci-imune ANCA-negativa e doença mista do tecido conjuntivo: relato de um caso

Abstract One of the most common causes of rapidly progressive glomerulonephritis (RPGN) is pauci-immune crescentic glomerulonephritis (CrGN). In the majority of cases, this condition has a positive serologic marker, the anti-neutrophil cytoplasmic antibodies (ANCAs), but in approximately 10% there are no circulating ANCAs, and this subgroup has been known as the ANCA-negative pauci-immune CrGN. RPGN can be associated with systemic diseases, but there are only few case reports describing the association with mixed connective tissue disease (MCTD). The authors report a case of ANCA-negative CrGN associated with a MCTD.

Resumo Uma das causas mais comuns da glomerulonefrite rapidamente progressiva (GNRP) é a glomerulonefrite crescêntica (GNC) pauci-imune. Na maioria dos casos, a patologia apresenta um marcador sorológico positivo, o anticorpo anticitoplasma de neutrófilos (ANCA), mas em cerca de 10% dos pacientes não há ANCAs circulantes, perfazendo um subgrupo da patologia conhecido como GNC pauci-imune ANCA-negativa. A GNRP pode estar associada a doenças sistêmicas, mas são poucos os relatos de caso que descrevem sua associação com doença mista do tecido conjuntivo (DMTC). O presente artigo relata um caso de GNC ANCA-negativa associada a DMTC.

Gremlin, A Potential Urinary Biomarker of Anca-Associated Crescentic Glomerulonephritis.

Gremlin renal overexpression has been reported in diabetic nephropathy, pauci-immune crescentic glomerulonephritis and chronic allograft nephropathy and has been implicated in the pathophysiology of the progression of renal damage. However, it is unknown whether urinary Gremlin can be associated with renal functional status, renal biopsy findings and outcome. To examine these associations we studied 20 patients with ANCA+ renal vasculitis and very high urinary Gremlin (354 ± 76 ug/gCr), 86 patients with other glomerular diseases and moderately elevated urinary Gremlin (83 ± 14 ug/gCr) and 11 healthy controls (urinary Gremlin 11.3 ± 2.4 ug/gCr). Urinary Gremlin was significantly correlated with renal expression of Gremlin (r = 0.64, p = 0.013) observed in cellular glomerular crescents, tubular epithelial cells and interstitial inflammatory cells. Moreover, urinary Gremlin levels were correlated with the number of glomerular crescents (r = 0.53; p < 0.001), renal CD68 positive cells (r = 0.71; p < 0.005), tubulointerstitial fibrosis (r = 0.50; p < 0.05), and serum creatinine levels (r = 0.60; p < 0.001). Interestingly, Gremlin expression was colocalized with CD68, CD163 (monocyte/macrophage markers) and CCL18 positive cells. ROC curve analysis showed that the cutoff value of urinary Gremlin in glomerular diseases as 43 ug/gCr with 72% of sensitivity and 100% of specificity [AUC: 0.96 (CI 95% 0.92-0.99] (p < 0.001). For ANCA+ renal vasculitis the value of urinary Gremlin of 241 ug/gCr had 55% of sensitivity and 100% of specificity [AUC: 0.81 (CI 95% 0.68-0.94) (p < 0.001]. Based on these results we propose that urinary Gremlin represents a non-invasive biomarker in ANCA+ renal vasculitis, and suggest a role of Gremlin in the formation of crescents.

Anca negative pauci-immune crescentic glomerulonephritis and mixed connective tissue disease: a case study.

One of the most common causes of rapidly progressive glomerulonephritis (RPGN) is pauci-immune crescentic glomerulonephritis (CrGN). In the majority of cases, this condition has a positive serologic marker, the anti-neutrophil cytoplasmic antibodies (ANCAs), but in approximately 10% there are no circulating ANCAs, and this subgroup has been known as the ANCA-negative pauci-immune CrGN. RPGN can be associated with systemic diseases, but there are only few case reports describing the association with mixed connective tissue disease (MCTD). The authors report a case of ANCA-negative CrGN associated with a MCTD.

Clinical Profile of Levamisole-Adulterated Cocaine-Induced Vasculitis/Vasculopathy: A 30-Case Series.

OBJECTIVES: The aims of this study were to describe clinical and laboratory manifestations of patients with levamisole-adulterated cocaine-induced vasculitis/vasculopathy and to propose a skin classification according to the distribution and severity of lesions. METHODS: We report the characteristics of 30 patients admitted with levamisole-adulterated cocaine-induced vasculitis/vasculopathy in 4 high-complexity institutions in Colombia, from December 2010 to May 2017. We compare our findings with the main published series. RESULTS: Median age was 31 years (interquartile range, 27-38 years) with a male-to-female ratio of 5:1. Eighty-three percent of the patients had retiform purpura affecting the limbs, buttocks, face, or abdomen; 73% had ear necrosis, 50% cutaneous ulcers, 17% genital necrosis, 13% oral ulcers, and 10% digital necrosis. Cutaneous involvement was classified according to the frequency of the compromised corporal area, and purpuric lesions were stratified in 4 grades of severity. Anti-neutrophil cytoplasmic autoantibodies were positive in 85% of the cases, lupus anticoagulant in 73%, and antinuclear autoantibodies in 57%; rheumatoid factor was negative in all cases. We found nephritis in 17 cases (57%). Prednisolone was used in most of the patients (70%), with other immunosuppressive agents being used in a lower percentage. Improvement was observed in 93% of the patients, but symptoms recurred in 40%, attributed to relapses in consumption. End-stage chronic renal disease developed in 10% of the cases, and 1 patient died. CONCLUSIONS: Because of rising cocaine consumption and levamisole adulteration frequency, levamisole-adulterated cocaine-induced vasculitis/vasculopathy is becoming more common. Detailed characterization of skin involvement coupled with multiple antibody positivity is essential for a diagnosis. Renal involvement is frequent, clinically and histologically heterogeneous, and potentially serious.

ANCA-Positive pauci-immune crescentic glomerulonephritis in a patient with systemic lupus erythematosus / Glomerulonefrite rapidamente progressiva ANCA-Positiva pauci-imune em paciente com lúpus eritematoso sistêmico

Abstract The pauci-immune crescentic glomerulonephritis (PICGN) is generally associated with small-vessel vasculitis with a few reported cases associated with other autoimmune diseases such as Systemic Lupus Erythematosus (SLE). We present the case of a female 34-year-old patient with acute kidney injury symptoms with indication for renal replacement therapy in the context of clinical SLE diagnosis. A kidney biopsy was conducted and it was found that most glomeruli showed some segmental sclerosis with synechia to the Bowman's capsule. 67% of the glomeruli had fibroepithelial crescents. Moreover, the interstitial space had a moderate lymphomononuclear infiltration and mild fibrosis. In the arterioles, there were walls thickened by subintimal sclerosis. Direct immunofluorescence detected limited IgM and C3 deposits in capillary loops and negative mensangium for IgG, IgA and C1q. A therapy using corticosteroids and intravenous cyclophosphamide was initiated with stable evolution. PICGN associated with SLE is a rare pathology with clinical presentation, varied evolution and without a standard medical treatment.

Resumo A glomerulonefrite rapidamente progressiva pauci-imune apresenta-se geralmente associada a vasculite de pequenos vasos, com poucos casos associados a outras doenças imunes como o lúpus eritematoso sistêmico (LES). Apresentamos no presente artigo o caso de uma mulher de 34 anos de idade com sintomas de insuficiência renal aguda e indicação de terapia renal substitutiva, no contexto de diagnóstico clínico de LES. A biópsia renal realizada revelou que a maioria dos glomérulos apresentavam um certo grau de esclerose segmentar e sinéquias com a cápsula de Bowman. Sessenta e sete por cento dos glomérulos apresentava crescentes fibroepiteliais. Além disso, o espaço intersticial exibia infiltrado linfomononuclear moderado e fibrose discreta. Nas arteríolas, as paredes encontravam-se espessadas por esclerose subintimal. A imunofluorescência direta detectou depósitos limitados de IgM e C3 nas alças capilares e mesângio negativo para IgG, IgA e C1q. Tratamento com corticosteroides e ciclofosfamida endovenosa foi iniciado com evolução estável. A glomerulonefrite rapidamente progressiva pauci-imune associada a LES é uma patologia rara com manifestação clínica e evolução variada, sem tratamento clínico padronizado.

ANCA-associated pauci-immune glomerulonephritis: always pauci-immune?

OBJECTIVES: Anti-neutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis (GN) is considered "pauci-immune" with absent or mild glomerular tuft staining for immunoglobulin (Ig) and/or complement. However, it is not unusual to see some immune deposits (ID) within glomeruli on immunofluorescence (IF). We determined to evaluate the prevalence and clinical significance of immune deposits in ANCA-associated GN. METHODS: We included all patients with ANCA associated vasculitis with renal biopsies between January 2002 and May 2014: granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis, microscopic polyangiitis and renal limited vasculitis. Patients were divided into Group A: biopsy without ID (≤2+ intensity of immunostaining) and Group B: biopsy with ID (>2+ intensity of immunostaining). Serum creatinine, estimated glomerular filtration rate (eGFR) at time of the biopsy, amount of proteinuria and hematuria, requirement of dialysis and extra renal involvement were recorded. RESULTS: Fifty-three patients (75.4% females) were included. Mean age at biopsy was 66.3 years. Typical pauci-immune GN was found in 39 patients (73.5%, group A). In 14 patients (26.4%, group B) examination revealed substantial deposition of Ig or complement in the mesangium and/or along the glomerular capillary wall. The only difference comparing both groups was significantly higher proteinuria in group B (mean 1.6/24 h (SD: 10.7) vs. 0.8/24 h (SD: 7.6), p=0.0036). CONCLUSIONS: In ANCA GN at least a quarter of patients were not "pauci-immune" (26.4%). In this subgroup, immune deposits were only associated with a significantly higher proteinuria. Further basic and clinical research is needed to elucidate the significance of immune deposition in ANCA GN.

ANCA-Positive pauci-immune crescentic glomerulonephritis in a patient with systemic lupus erythematosus.

The pauci-immune crescentic glomerulonephritis (PICGN) is generally associated with small-vessel vasculitis with a few reported cases associated with other autoimmune diseases such as Systemic Lupus Erythematosus (SLE). We present the case of a female 34-year-old patient with acute kidney injury symptoms with indication for renal replacement therapy in the context of clinical SLE diagnosis. A kidney biopsy was conducted and it was found that most glomeruli showed some segmental sclerosis with synechia to the Bowman's capsule. 67% of the glomeruli had fibroepithelial crescents. Moreover, the interstitial space had a moderate lymphomononuclear infiltration and mild fibrosis. In the arterioles, there were walls thickened by subintimal sclerosis. Direct immunofluorescence detected limited IgM and C3 deposits in capillary loops and negative mensangium for IgG, IgA and C1q. A therapy using corticosteroids and intravenous cyclophosphamide was initiated with stable evolution. PICGN associated with SLE is a rare pathology with clinical presentation, varied evolution and without a standard medical treatment.

Acute Antibody-Mediated Rejection in Kidney Transplant Based on the 2013 Banff Criteria: Single-Center Experience in Uruguay.

BACKGROUND: Acute antibody-mediated rejection (AMR) diagnosis criteria have changed in recent consensus of Banff, with current evidence of C4d-negative AMR. Our objective was to evaluate incidence of AMR in renal transplantation according to Banff 2013 criteria and to examine the histological features and outcome. METHODS: This retrospective study involved all kidney transplants with histological diagnosis of acute rejection (AR) at our center between 2000 and 2014. All the biopsies with AR were re-assessed by a nephro-pathologist and classified by use of the Banff 2013 criteria. RESULTS: Of 205 kidney transplants, biopsy-proven AR was diagnosed in 25 cases (12%). Re-assessing them according to Banff 2013 criteria, AMR was diagnosed in 17 (8.3%) and represented 68% of the confirmed rejections. AMR diagnosis was performed on day 23 ± 26, with median of 11 days. From the 17 cases, 7 had concomitant T-cell-mediated rejection. All cases presented endothelial edema and acute tubular necrosis. Glomerulitis was found in 12 cases and capillaritis in 14. In 3, associated thrombotic micro-angiopathy (TMA) was found. Intimal and transmural arteritis was evidenced in 5 and 1 patient. In 2, transplant glomerulopathy was present. Seven of the 10 biopsies with C4d staining in the peri-tubular capillaries were positive. Twelve cases received plasmapheresis, 6 received gamma-globulin, and 6 received rituximab. After administration of anti-AMR therapy, 16 cases recovered renal function, reaching a serum creatinine level of 1.5 ± 0.6 mg %. Graft survival at 1 year was lower in the AMR group versus patients without AMR (81.9% vs 98.9%, log-rank test, P < .001). Risk factors for AMR were re-transplant (30% vs 7%, P = .02), HLA-DR mismatch (1.06 ± 0.65 vs 0.7 ± 0.6, P = .03), panel-reactive antibody (28% ± 33 vs 6.2 ± 13, P = .00), and delayed graft function (82% vs 30%, P = .00). CONCLUSIONS: Adapting the new Banff 2013 criteria increased the sensitivity of the diagnosis of ARM. Regarding our data, despite an adequate response to the therapy, it resulted in a worse graft survival by the first year of renal transplant.

An Animal Model Using Metallic Ions to Produce Autoimmune Nephritis.

Autoimmune nephritis triggered by metallic ions was assessed in a Long-Evans rat model. The parameters evaluated included antinuclear autoantibody production, kidney damage mediated by immune complexes detected by immunofluorescence, and renal function tested by retention of nitrogen waste products and proteinuria. To accomplish our goal, the animals were treated with the following ionic metals: HgCl2, CuSO4, AgNO3, and Pb(NO3)2. A group without ionic metals was used as the control. The results of the present investigation demonstrated that metallic ions triggered antinuclear antibody production in 60% of animals, some of them with anti-DNA specificity. Furthermore, all animals treated with heavy metals developed toxic glomerulonephritis with immune complex deposition along the mesangium and membranes. These phenomena were accompanied by proteinuria and increased concentrations of urea. Based on these results, we conclude that metallic ions may induce experimental autoimmune nephritis.

Abatacept and Glomerular Diseases: The Open Road for the Second Signal as a New Target is Settled Down.

Glomerulopathy is the third most important cause of kidney disease. Proteinuria is the hallmark of glomerular damage, and a marker of progression of kidney disease, cardiovascular morbidity and mortality. Strategies to reduce proteinuria are partially successful, and despite proteinuria management, renal disease may still progress. Immunosuppression to treat glomerulopathies is nonspecific, partially effective and presents side-effects. It is critical to find safe drugs with specific podocyte molecular targets. Podocytes contain a complex array of proteins. Lymphocyte activation antigen B7-1 (CD80) is located on antigen presenting cells modulating CD4+ and CD8+ T cells by interacting with co-stimulator CD28, a glycoprotein located on T-cells, or with cytotoxic T-lymphocyte protein 4 (CTLA-4) co-inhibitor. Normally, podocytes do not express B7-1. However, certain glomerulopathies are associated with an increase on the surface of podocytes of B7-1, which reduces the ability of podocytes to attach to the surrounding glomerular basement membrane, favouring podocyturia and proteinuria. When the B7-1-CTLA-4 interaction takes place, the immune response is abrogated, while a B7-1-CD28 coupling leads to T cell activation. Abatacept binds to B7-1 by blocking the CD28 or potentiating the CTLA-4 signals. In B7-1 positive podocytes, abatacept may be a specific tool to decrease proteinuria. Selected patents are also briefly presented in this review.

IgM nephropathy in children: clinicopathologic analysis.

INTRODUCTION: IgM nephropathy (IgMN) is a glomerulonephritis characterised by diffuse mesangial immunoglobulin M (IgM) deposits. It usually presents with nephrotic range proteinuria and, according to some previous work, it occurs most often in patients who are resistant to or dependent on steroid treatment. OBJECTIVE: To perform a clinical, histological and immunopathological description and assess the response to steroid treatment of paediatric patients diagnosed with nephrotic syndrome and diffuse mesangial IgM deposits. METHOD: This is a descriptive, retrospective study carried out in two hospitals, where the clinical records of paediatric patients with IgMN were analysed and the histological sections were re-assessed. RESULTS: thirteen children were included in this study. IgMN corresponded to 5.17% of all paediatric renal biopsies. The age of patients ranged from 1 year to 12 years (median: 2 years), 46.7% were women. The most common morphological finding was diffuse mesangial hypercellularity (46.1%), followed by focal segmental glomerulosclerosis (30.8%) and minimal glomerular changes (23.1%). All patients received steroids; in 4 cases (30.7%) as the only immunosuppressant medication, 3 (23.1%) also received cyclophosphamide, 5 (38.4%) mycophenolate, and 1 (7.7%) cyclosporine. Seven patients (53.8%) had frequent relapses, 5 (38.5%) were cortico-resistant and 1 (7.7%) cortico-dependent. Two patients (15.38%) had chronic impairment of renal function. CONCLUSION: The presence of diffuse mesangial IgM in paediatric patients with nephrotic syndrome is not a very uncommon finding; its clinical presentation has been associated with lower response to steroids. However, the long-term prognosis of these patients is still unknown.

[Rapidly progressive crescentic glomerulonephritis in the elderly]. / Glomerulonefritis rápidamente progresiva en ancianos.

Rapidly progressive glomerulonephritis (RPGN) is a syndrome characterized by glomerular lesions giving rise to acute renal injury that develops within a brief period of time, usually days or a few months. It is classified according to the underlying mechanism of injury and the immunofluorescence findings into four main disorders. In the last decade, nephrologists have witnessed a steady rise in the mean age of the patients diagnosed with RPGN. This observation may reflect an increase in the incidence of this entity and also a more timely diagnosis. We present 3 cases of RPGN in elderly patients, diagnosed within a 3 month period at our institution which illustrates the spectrum of these conditions.

Glomerulonefritis rápidamente progresiva en ancianos / Rapidly progressive crescentic glomerulonephritis in the elderly

La glomerulonefritis rápidamente progresiva (GNRP) es un síndrome clínico que se caracteriza por la presencia de signos urinarios de enfermedad glomerular e insuficiencia renal de desarrollo en un lapso de días a pocos meses. La inmunofluorescencia permite clasificar a las GNRP en cuatro tipos según se identifiquen o no depósitos inmunes y, si están presentes, de acuerdo con su naturaleza. En la última década se ha demostrado un aumento constante en el promedio de edad de los pacientes con GNRP. Este fenómeno podría reflejar tanto una mayor incidencia de la enfermedad, como un incremento en la tasa de diagnóstico. Se presentan 3 casos de GNRP en adultos mayores de 65 años, diagnosticados en un periodo de 3 meses en nuestra institución.

Rapidly progressive glomerulonephritis (RPGN) is a syndrome characterized by glomerular lesions giving rise to acute renal injury that develops within a brief period of time, usually days or a few months. It is classified according to the underlying mechanism of injury and the immunofluorescence findings into four main disorders. In the last decade, nephrologists have witnessed a steady rise in the mean age of the patients diagnosed with RPGN. This observation may reflect an increase in the incidence of this entity and also a more timely diagnosis. We present 3 cases of RPGN in elderly patients, diagnosed within a 3-month period at our institution which illustrates the spectrum of these conditions.

Glomerulonefritis rápidamente progresiva en ancianos / Rapidly progressive crescentic glomerulonephritis in the elderly

La glomerulonefritis rápidamente progresiva (GNRP) es un síndrome clínico que se caracteriza por la presencia de signos urinarios de enfermedad glomerular e insuficiencia renal de desarrollo en un lapso de días a pocos meses. La inmunofluorescencia permite clasificar a las GNRP en cuatro tipos según se identifiquen o no depósitos inmunes y, si están presentes, de acuerdo con su naturaleza. En la última década se ha demostrado un aumento constante en el promedio de edad de los pacientes con GNRP. Este fenómeno podría reflejar tanto una mayor incidencia de la enfermedad, como un incremento en la tasa de diagnóstico. Se presentan 3 casos de GNRP en adultos mayores de 65 años, diagnosticados en un periodo de 3 meses en nuestra institución.(AU)

Rapidly progressive glomerulonephritis (RPGN) is a syndrome characterized by glomerular lesions giving rise to acute renal injury that develops within a brief period of time, usually days or a few months. It is classified according to the underlying mechanism of injury and the immunofluorescence findings into four main disorders. In the last decade, nephrologists have witnessed a steady rise in the mean age of the patients diagnosed with RPGN. This observation may reflect an increase in the incidence of this entity and also a more timely diagnosis. We present 3 cases of RPGN in elderly patients, diagnosed within a 3-month period at our institution which illustrates the spectrum of these conditions.(AU)