RESUMO
INTRODUCTION: Membranous nephropathy (MN) is the most common cause of primary nephrotic syndrome in adults (20-30%). Light microscopy shows thickening of glomerular basement membrane with appearance of spikes. These histological findings are not evident in early forms, in which case the granular deposition pattern of IgG and/or C3 in the basement membrane by immunofluorescence (IF) constitutes the diagnostic tool that allows to differentiate it from minimal change disease (MCD). Complement system plays a key role in the pathophysiology of MN. C4d is a degradation product and a marker of the complement system activation. C4d labelling by immunohistochemical (HI) technique can help in the differential diagnosis between both glomerulopathies NM and MCD when the material for IF is insufficient and light microscopy is normal. Our objective was to explore the discrimination power of C4d to differentiate between MN and MCD in renal biopsy material. METHODS: Paraffin-embedded samples were recovered from renal biopsies with a diagnosis of MN and MCD performed between 1/1/2008 and 4/1/2019. IH staining was performed by immunoperoxidase technique using a rabbit anti-human C4d polyclonal antibody. RESULTS: In all cases with MN (n = 27, 15 males) with a median age of 63 (range: 18-87) years, C4d deposits were detected. In 21 cases with MCD (12 males) with a median age of 51 (range: 18-87) years, the C4d marking was negative in every samples. CONCLUSION: The results indicate that the marking of the renal biopsy with C4d is a useful tool for the differential diagnosis between NM and MCD.
Introducción: La nefropatía membranosa (NM) es la causa más frecuente de síndrome nefrótico primario en adultos (20-30%). En la microscopia óptica se observa engrosamiento de membrana basal glomerular con aparición de espigas. Estos hallazgos histológicos no son evidentes en formas tempranas, en cuyo caso el patrón de depósito granular de IgG y/o C3 en la membrana basal por inmunofluorescencia (IF) permite diferenciarla de enfermedad por cambios mínimos (ECM). El sistema del complemento juega un papel central en la fisiopatología de la NM. C4d es producto de degradación y un marcador de la activación del complemento. La marcación con C4d en muestras de biopsias renales, por técnica de inmunohistoquímica (IH) puede colaborar en el diagnóstico diferencial entre ambas glomerulopatías. Nuestro objetivo fue explorar el poder de discriminación del C4d para diferenciar NM de ECM en material de biopsias renales. Métodos: Se recuperaron muestras en parafina de biopsias renales con diagnóstico de NM y ECM realizados entre 1/1/2008 y 1/4/2019. Se realizaron tinciones de IH por técnica de inmunoperoxidasa con C4d usando un anticuerpo policlonal antihumano de conejo. Resultados: En todos los casos con NM (n = 27, 15 hombres) con mediana de edad de 63 (rango: 18-86) años se detectaron depósitos de C4d. En los 21 casos con ECM (12 hombres) con mediana de edad de 51 (rango: 18-87) años la marcación de C4d fue negativa. Conclusión: Los resultados indican que la marcación de la biopsia renal con C4d es una herramienta útil para el diagnóstico diferencial entre NM y ECM.
Assuntos
Complemento C4b , Glomerulonefrite Membranosa , Glomerulonefrite Membranosa/diagnóstico , Glomerulonefrite Membranosa/patologia , Glomerulonefrite Membranosa/imunologia , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Feminino , Idoso , Complemento C4b/análise , Adulto Jovem , Diagnóstico Diferencial , Idoso de 80 Anos ou mais , Adolescente , Biópsia , Biomarcadores/análise , Nefrose Lipoide/patologia , Nefrose Lipoide/diagnóstico , Fragmentos de Peptídeos/análise , Estudos RetrospectivosRESUMO
INTRODUCTION: Percutaneous kidney biopsy (KB) is crucial to the diagnosis and management of several renal pathologies. National data on native KB in pediatric patients are scarce. We aimed to review the demographic and clinical characteristics and histopathological patterns in children who underwent native percutaneous KB over 24 years. METHODS: Retrospective observational study of patients undergoing native percutaneous KB in a pediatric nephrology unit between 1998 and 2021, comparing 3 periods: period 1 (1998-2005), period 2 (2006-2013), and period 3 (2014-2021). RESULTS: We found that 228 KB were performed, 78 (34.2%) in period 1, 91 (39.9%) in period 2, and 59 (25.9%) in period 3. The median age at KB was 11 (7-14) years. The main indications for KB were nephrotic syndrome (NS) (42.9%), hematuria and/or non-nephrotic proteinuria (35.5%), and acute kidney injury (13.2%). Primary glomerulopathies were more frequent (67.1%), particularly minimal change disease (MCD) (25.4%), IgA nephropathy (12.7%), and mesangioproliferative glomerulonephritis (GN) (8.8%). Of the secondary glomerulopathies, lupus nephritis (LN) was the most prevalent (11.8%). In group 1, hematuria and/or non-nephrotic proteinuria were the main reasons for KB, as opposed to NS in groups 2 and 3 (p < 0.01). LN showed an increasing trend (period 1-3: 2.6%-5.3%) and focal segmental glomerular sclerosis (FSGS) showed a slight decreasing trend (period 1-3: 3.1%-1.8%), without statistical significance. CONCLUSIONS: The main indication for KB was NS, which increased over time, justifying the finding of MCD as main histological diagnosis. LN showed an increase in incidence over time, while FSGS cases did not increase.
Assuntos
Glomerulonefrite por IGA , Glomerulosclerose Segmentar e Focal , Nefropatias , Nefrite Lúpica , Nefrose Lipoide , Síndrome Nefrótica , Criança , Humanos , Adolescente , Glomerulosclerose Segmentar e Focal/patologia , Hematúria/epidemiologia , Hematúria/etiologia , Hematúria/patologia , Portugal/epidemiologia , Rim/patologia , Nefropatias/epidemiologia , Nefropatias/patologia , Síndrome Nefrótica/diagnóstico , Nefrite Lúpica/patologia , Glomerulonefrite por IGA/patologia , Proteinúria , Estudos Retrospectivos , BiópsiaRESUMO
Minimal Change Disease (MCD) and Focal Segmental Glomerulosclerosis (FSGS) are the main causes of nephrotic syndrome in the world. The complement system appears to play an important role in the pathogenesis of these diseases. To evaluate the deposition of immunoglobulins and particles of the complement system in renal biopsies of patients with FSGS and MCD and relate to laboratory data, we selected 59 renal biopsies from patients with podocytopathies, 31 from patients with FSGS and 28 with MCD. Epidemiological, clinical, laboratory information and the prognosis of these patients were evaluated. Analysis of the deposition of IgM, IgG, C3, C1q and C4d in renal biopsies was performed. We related IgM and C3 deposition with laboratory parameters. Statistical analysis was performed using GraphPad Prism version 7.0. Glomerular deposition of IgM was significantly higher in the FSGS group, as was codeposition of IgM and C3. The clinical course of patients and laboratory data were also worse in cases of FSGS, with a higher percentage progressing to chronic kidney disease and death. Patients with C3 deposition had significantly higher mean serum creatinine and significantly lower eGFR, regardless of disease. Patients with FSGS had more IgM and C3 deposition in renal biopsies, worse laboratory data and prognosis than patients with MCD. C3 deposition, both in FSGS and MCD, appears to be related to worsening renal function.
Assuntos
Complemento C3 , Glomerulosclerose Segmentar e Focal , Imunoglobulina M , Glomérulos Renais , Nefrose Lipoide , Humanos , Imunoglobulina M/metabolismo , Complemento C3/metabolismo , Glomerulosclerose Segmentar e Focal/patologia , Glomerulosclerose Segmentar e Focal/metabolismo , Glomerulosclerose Segmentar e Focal/imunologia , Feminino , Masculino , Adulto , Glomérulos Renais/patologia , Glomérulos Renais/metabolismo , Pessoa de Meia-Idade , Nefrose Lipoide/patologia , Nefrose Lipoide/metabolismo , Podócitos/patologia , Podócitos/metabolismo , Adulto Jovem , Adolescente , Prognóstico , Biópsia , Síndrome Nefrótica/metabolismo , Síndrome Nefrótica/patologia , Síndrome Nefrótica/imunologia , IdosoRESUMO
Introducción: La enfermedad de cambios mínimos es una causa rara de síndrome nefrótico en el adulto, y su relación con el hipotiroidismo es más rara aún. Se considera que esta patología renal responde favorablemente al manejo con glucocorticoides y tiene una baja frecuencia de resistencia. Su abordaje hoy en día es objeto de investigación. Objetivo: Describir una rara etiología de síndrome nefrótico en el adulto con presentación, tratamiento y desenlace infrecuentes. Presentación del caso: Paciente femenino de 53 años quien inicia con síndrome nefrótico por enfermedad de cambios mínimos cortico-resistente y su asociación con un hipotiroidismo descontrolado, quien requiere manejo con rituximab y control de la enfermedad endocrinológica asociada, como enfermedad de base. Conclusiones: En este caso clínico se muestra como las enfermedades citadas pueden coexistir y el tratamiento en conjunto es necesario. El establecimiento de nuevas terapias en la población adulta como el rituximab podría mostrar beneficio, como en este caso. Sin embargo, aún existe la necesidad de estudios de mayor evidencia que validen firmemente la efectividad de los diferentes tratamientos en este tipo de pacientes.
Introduction: Minimal change disease is a rare cause of nephrotic syndrome in adults, and its association with hypothyroidism is even more exceptional. This renal pathology is considered to respond favorably to glucocorticoid management and has a low resistance frequency. How to approach this disease is currently under investigation. Objective: To describe a rare etiology of adult nephrotic syndrome with unusual presentation, treatment, and outcome. Case presentation: A 53 years-old female patient who initially experienced nephrotic syndrome due to steroid-resistant minimal change disease, which was also associated with uncontrolled hypothyroidism. She required management with rituximab and control of the associated endocrinological disease, which was considered as the underlying disease. Conclusions: This clinical case shows (i) how the two aforementioned diseases can coexist and (ii) that a joint treatment is necessary. Establishing new therapies may be beneficial for adult populations, such as the benefits seen in this case with the use of rituximab. However, further studies are needed to strongly validate the effectiveness of the different treatments for these types of patients.
Assuntos
Humanos , Pessoa de Meia-Idade , Doenças da Glândula Tireoide , Nefrose , Hipotireoidismo , Nefrose Lipoide , Síndrome NefróticaRESUMO
INTRODUCTION: Treatment of nephrotic syndrome with corticosteroid can cause several side- effects including behavioral abnormalities. The objectives of the study were to observe the proportion of non-relapsers having persistence of behavioral abnormalities after completion of treatment of initial episode and compare the abnormalities with relapsers, and to determine risk factors for persistence. METHODS: Seventy-five children with a first episode of idiopathic nephrotic syndrome and 60 normal children were rated by parents for behavioral problems using the Child Behavior Checklist. The Parenting Stress Index was also evaluated. The children were rated before treatment and 12 and 36 weeks after. RESULTS: Both relapsers and non-relapsers showed abnormalities in internalizing and externalizing domains at 12 weeks of steroid therapy. Non-relapsers had abnormal scores in the internalizing domain in 63.5 % and externalizing domain in 48.1% of cases at 36 weeks. Relapsers had abnormal scores in all the three behavior domains, but a significantly higher proportion of relapsers had abnormal scores regarding total behavior (65.2% vs 28.8%, p<0.01) and child domains (100% vs 57.7%, p<0.001) of Parenting Stress Index in comparison to non-relapsers at 36 weeks. Occurrence of relapse increased the risk (odds ratio 5.76, 95% CI 1.35-10.76, p< 0.001) for persistence of abnormal total behavior at 36 weeks follow-up. CONCLUSION: Persistence of abnormalities was observed not only in relapsers but also in non-relapsers. Relapse was found to be a significant risk factor for persistence of abnormal behaviors in these patients.
Assuntos
Nefrose Lipoide , Síndrome Nefrótica , Comportamento Problema , Criança , Glucocorticoides/efeitos adversos , Humanos , Síndrome Nefrótica/tratamento farmacológico , Estudos Prospectivos , RecidivaRESUMO
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.
Assuntos
Injúria Renal Aguda/patologia , COVID-19/patologia , Glomerulonefrite/patologia , Rim/patologia , Microangiopatias Trombóticas/patologia , Injúria Renal Aguda/sangue , Injúria Renal Aguda/imunologia , Imunidade Adaptativa/imunologia , Arteriosclerose/imunologia , Arteriosclerose/patologia , COVID-19/sangue , COVID-19/imunologia , Citocinas/imunologia , Glomerulonefrite/imunologia , Glomerulonefrite por IGA/imunologia , Glomerulonefrite por IGA/patologia , Glomerulosclerose Segmentar e Focal/imunologia , Glomerulosclerose Segmentar e Focal/patologia , Humanos , Imunidade Inata/imunologia , Infarto/imunologia , Infarto/patologia , Rim/irrigação sanguínea , Rim/imunologia , Necrose do Córtex Renal/imunologia , Necrose do Córtex Renal/patologia , Nefrite Intersticial/imunologia , Nefrite Intersticial/patologia , Nefrose Lipoide/imunologia , Nefrose Lipoide/patologia , Rabdomiólise , SARS-CoV-2 , Trombofilia/sangue , Microangiopatias Trombóticas/imunologiaRESUMO
ABSTRACT Minimal change disease accounts for up to 25% of the cases of nephrotic syndrome in adult population. The allergic mechanism has been associated with minimal change disease and allergens have been implied, namely insect stings. We present a case report of a woman with new onset of nephrotic syndrome after a non-hymenoptera insect sting, with biopsy-proven minimal change disease, that was accompanied by a pulmonary thromboembolism process. Complete remission with glucocorticoid therapy was observed, with sustained response for 6 months after discontinuation. A new exposure to insect sting in the same geographical region and season triggered a nephrotic syndrome relapse. Subsequent avoidance of the place resulted in a sustained remission for more than 4 years.
RESUMO A doença de lesões mínimas é responsável por até 25% dos casos de síndrome nefrótica na população adulta. O mecanismo alérgico tem sido associado à doença de lesão mínima a associada a alérgenos, como picadas de insetos. Apresentamos um caso de uma mulher com início recente de síndrome nefrótica após picada de inseto não himenóptero, com doença de lesões mínimas comprovada por biópsia, acompanhada por um processo de tromboembolismo pulmonar. A paciente teve remissão completa com glicocorticoides, com resposta sustentada por 6 meses após a interrupção do tratamento. Uma nova exposição à picada de inseto na mesma região geográfica e estação do ano provocou uma recaída da síndrome nefrótica. Evitar o local subsequentemente resultou em remissão sustentada por mais de 4 anos.
Assuntos
Humanos , Feminino , Adulto , Mordeduras e Picadas de Insetos/complicações , Nefrose Lipoide , Síndrome Nefrótica/etiologia , Biópsia , Indução de RemissãoRESUMO
Podocyte injury in focal segmental glomerulosclerosis (FSGS) and minimal change disease (MCD) results from the imbalance between adaptive responses that maintain homeostasis and cellular dysfunction that can culminate in cell death. Therefore, an in situ analysis was performed to detect morphological changes related to cell death and autophagy in renal biopsies from adult patients with podocytopathies. Forty-nine renal biopsies from patients with FSGS (n = 22) and MCD (n = 27) were selected. In situ expression of Wilms Tumor 1 protein (WT1), light chain microtubule 1-associated protein (LC3) and caspase-3 protein were evaluated by immunohistochemistry. The foot process effacement and morphological alterations related to podocyte cell death and autophagy were analyzed with transmission electronic microscopy. Reduction in the density of WT1-labeled podocytes was observed for FSGS and MCD cases as compared to controls. Foot process width (FPW) in control group was lower than in cases of podocytopathies. In FSGS group, FPW was significantly higher than in MCD group and correlated with proteinuria. A density of LC3-labeled podocytes and the number of autophagosomes in podocytes/ pedicels were higher in the MCD group than in the FSGS group. The number of autophagosomes correlated positively with the estimated glomerular filtration rate in cases of MCD. The density of caspase-3-labeled podocytes in FSGS and MCD was higher than control group, and a higher number of podocytes with an evidence of necrosis was detected in FSGS cases than in MCD and control cases. Podocytes from patients diagnosed with FSGS showed more morphological and functional alterations resulting from a larger number of lesions and reduced cell adaptation.
Assuntos
Glomerulosclerose Segmentar e Focal/patologia , Nefrose Lipoide/patologia , Podócitos/patologia , Adulto , Autofagossomos/metabolismo , Autofagia , Estudos de Casos e Controles , Caspase 3/metabolismo , Feminino , Taxa de Filtração Glomerular , Glomerulosclerose Segmentar e Focal/metabolismo , Humanos , Rim/metabolismo , Rim/patologia , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Pessoa de Meia-Idade , Necrose , Nefrose Lipoide/metabolismo , Podócitos/citologia , Podócitos/metabolismo , Proteinúria/complicações , Proteínas WT1/metabolismoRESUMO
Minimal change disease accounts for up to 25% of the cases of nephrotic syndrome in adult population. The allergic mechanism has been associated with minimal change disease and allergens have been implied, namely insect stings. We present a case report of a woman with new onset of nephrotic syndrome after a non-hymenoptera insect sting, with biopsy-proven minimal change disease, that was accompanied by a pulmonary thromboembolism process. Complete remission with glucocorticoid therapy was observed, with sustained response for 6 months after discontinuation. A new exposure to insect sting in the same geographical region and season triggered a nephrotic syndrome relapse. Subsequent avoidance of the place resulted in a sustained remission for more than 4 years.