Resumo Os anticorpos anticitoplasma de neutrófilos (ANCAs) estão associados à vasculite de pequenos vasos, no entanto, a sua prevalência não é rara em outras doenças imunológicas. Na nefrite lúpica (LN), o seu papel patológico e relevância clínica têm sido alvo de pontos de vista controversos. Apresentamos um caso de lesão renal aguda e síndrome nefrótica em uma jovem com nefrite proliferativa difusa e membranosa em sua biópsia renal, muito alusivo a NL classe IV + V, com um padrão full house na imunofluorescência, mas sem critérios clínicos e achados laboratoriais para corroborar o diagnóstico de lúpus eritematoso sistêmico (LES). Não obstante, a paciente apresentou títulos elevados de ANCA, que diminuiram progressivamente com a melhoria da função renal e da proteinúria, após tratamento com micofenolato de mofetil (MMF) e esteróide. Os autores acreditam que se trata de um caso de nefrite semelhante à nefrite lúpica, em que os ANCAs são marcadores imunológicos, embora não estejam diretamente envolvidos na patogênese.

Abstract Antineutrophil cytoplasmic antibodies (ANCAs) are associated with small vessel vasculitis but their prevalence is not rare in other immune diseases. In lupus nephritis (LN), their pathological role and clinical relevance have been the target of controversial views. We present a case of acute kidney injury and nephrotic syndrome in a young woman with diffuse global proliferative and membranous nephritis on her kidney biopsy, showing a full-house immunofluorescence pattern, very allusive of class IV + V LN, but lacking associated clinical criteria and laboratory findings to support the diagnosis of systemic lupus erythematosus (SLE). Furthermore, the patient presented with high titers of ANCA, steadily decreasing alongside the renal function and proteinuria improvements, with mycophenolate mofetil (MMF) and steroid treatment. The authors believe this is a case of lupus-like nephritis, in which ANCAs are immunological markers, although they are not directly involved in the pathogenesis.

ABSTRACT Peritoneal dialysis (PD) relies on adequate function of PD catheter. Mechanical complications are a major cause of dropout among PD patients. A prompt timing and an appropriate intervention may overcome these problems with catheter salvage, without interrupting PD treatment. Many Portuguese centers still lack a proper articulation between nephrology and surgical departments. We describe current available surgical approaches in the implantation of PD catheters, management of mechanical complications, exit‑site infections and other abdominal surgical procedures. Our aim is to reinforce the need for an established protocol of action between these departments as occurs with vascular access in hemodialysis.

ABSTRACT Background: There is an ongoing increasing focus on person‑centered individualized dialysis prescription. For this model, incremental peritoneal dialysis has been established as a strategy to start peritoneal dialysis, with an intention to increase the dose of peritoneal dialysis, as a consequence of renal clearance declines. In spite of being broadly accepted, the evidence of non‑inferiority of the incremental approach in comparison with full dose peritoneal dialysis is weak. To disclose the possibility and safety of an incremental approach in incident patients, we assessed patients and technique survival (main outcomes) between incremental and full dose peritoneal dialysis. We also compared the effects in the clinical parameters of adequacy, urinary output and peritonitis incidence in both approaches. Methods: Following a retrospective design, we undertook an observational study in our center over 20 years. We investigated 106 patients divided into two groups, according to initial peritoneal dialysis strategy (incremental or full dose). We used multivariate multinomial model to assess predictors of peritonitis. The main outcomes were studies using a competing risk model. Results: One year after peritoneal dialysis start, our data disclosed statistically significant differences of phosphatemia and solute removal between full dose and incremental approach, favoring the latter. In an incremental approach, two or more peritoneal infections and drop out to hemodialysis were less usual. Conclusions: Incremental peritoneal prescription seems to be a good choice to start peritoneal dialysis. Potential benefits and, above all, safety reinforce the adoption of incremental peritoneal dialysis in incident patients as a strategy of individualized care, in compliance with new guidelines.

Resumo As glomerulopatias figuram entre as principais causas de doença renal terminal. Nos últimos anos, a pesquisa clínica efetuou contribuições significativas para a compreensão desse grupo de patologias. Recentemente, o rituximabe (RTX) surgiu como um tratamento razoavelmente seguro. As diretrizes do Kidney Disease: Improving Global Outcomes (KDIGO) recomendam o RTX apenas como tratamento inicial na vasculite associada ao ANCA (VAA) e em pacientes não respondedores com nefrite lúpica (NL), embora não sejam atualizadas desde 2012. Atualmente, o RTX parece ser pelo menos tão eficaz quanto outros esquemas imunossupressores na nefropatia membranosa idiopática (NMI). Na doença por lesão mínima (DLM), o medicamento pode proporcionar um período de remissão duradouro em pacientes córtico-dependentes ou com recidivas frequentes. Resultados preliminares corroboram o uso de RTX em pacientes com NL membranosa pura e glomerulonefrite membranoproliferativa (GNMP) mediada por imunoglobulina, mas não em pacientes com NL classe III/IV ou GNMP mediada por complemento. Os achados a respeito de glomeruloesclerose segmentar e focal (GESF) idiopática e doença por anticorpo antimembrana basal glomerular (anti-MBG) não são conclusivos em função do pequeno número, porte e heterogeneidade dos estudos publicados até o presente momento. Por fim, a imunossupressão com RTX não é particularmente útil na nefropatia por IgA. A presente revisão apresenta o racional da prescrição de RTX nas diferentes glomerulopatias, desfechos e segurança. Nesse sentido, foram incluídos ensaios clínicos randomizados (ECRs) realizados em adultos, sempre que possível. Pesquisas bibliográficas foram realizadas nas bases de dados do clinictrials.gov e no PubMed.

Abstract Glomerulopathies are one of the leading causes of end-stage renal disease. In the last years, clinical research has made significant contributions to the understanding of such conditions. Recently, rituximab (RTX) has appeared as a reasonably safe treatment. The Kidney Disease: Improving Global Outcomes guidelines (KDIGO) recommended RTX only as initial treatment in antineutrophil cytoplasm antibody associated vasculitis (AAV) and in non-responders patients with lupus nephritis (LN), but these guidelines have not been updated since 2012. Nowadays, RTX seems to be at least as effective as other immunosuppressive regimens in idiopathic membranous nephropathy (IMN). In minimal-change disease, (MCD) this drug might allow a long-lasting remission period in steroid-dependent or frequently relapsing patients. Preliminary results support the use of RTX in patients with pure membranous LN and immunoglobulin-mediated membranoproliferative glomerulonephritis (MPGN), but not in patients with class III/IV LN or complement-mediated MPGN. No conclusion can be drawn in idiopathic focal segmental glomerulosclerosis (FSGS) and anti-glomerular basement membrane antibody glomerulonephritis (anti-GBM GN) because studies are small, heterogeneous, and scarce. Lastly, immunosuppression including RTX is not particularly useful in IgA nephropathy. This review presents the general background, outcomes, and safety for RTX treatment in different glomerulopathies. In this regard, we describe randomized controlled trials (RCTs) performed in adults, whenever possible. A literature search was performed using clinicaltrials.gov and PubMed.

Introduction: Peritonitis is a common complication in peritoneal dialysis patients and a major cause for dropout. Systematic report and frequent trend analysis are thought to be major drivers for improvement in this area. The authors analysed peritonitis outcomes dating back over 20 years in a peritoneal dialysis unit of a central hospital. Methods: Retrospective study from 1993 to 2018: assessment of demographic, clinical and microbiological profiles of patients with peritonitis. We performed univariate and multivariate analysis (multiple logistic regression) to predict peritonitis risk factors, and survival analysis (Cox proportional hazards model) to determine the impact on outcomes (mortality and technique survival). Results: We included 225 patients, average age of 48.3±14.7 years, average time of follow-up of 38±25 months, with a total of 221 episodes of peritonitis (0.31 peritonitis/patient.year), 76% resulting in cure. Most frequent agents were Staphylococci: Coagulase-Negative (23%) and Staphylococcus aureus (19%, of which 24% were methicillin-resistant). Gram-negative infections led to higher rate of catheter removal, transfer to hemodialysis or death (49% of cases vs. 17% in Gram-positive). Primary end-point was death or transfer to hemodialysis, with a median time of 94 (min 4, max 94) and 66 (min 3, max 105) months, respectively. The occurrence of at least one peritonitis was the major variable that influenced transfer to hemodialysis (OR 3.94 [2.12 - 7.58], p < 0.001*], whereas an event in the first year also negatively affected the time to dialysis technique switch (median time 38.7 [26.2 - 58.4] vs. 67.8 [59.5 - 80.3] months, log-rank = 0.02*), but without impact on mortality. Only the peritoneal dialysis modality (OR: automated peritoneal dialysis vs. continuous ambulatory peritoneal dialysis 0.38 [0.19-0.74]) was predictive of peritonitis in multivariate analysis. Conclusions: In this single-center long-term analysis, where the rate of peritonitis was within recommended values, automated peritoneal dialysis seemed to have a protective impact. The number of peritonitis and peritonitis occurrence during the first year worsened technique survival, emphasizing early peritonitis prevention.

A successful peritoneal dialysis program follows evidence-based practice guidelines. In this first article we review the current guidelines on catheter insertion and on prevention of catheter-related infections, both subjects of extreme importance not only to initiate and also to maintain patients on peritoneal dialysis. The treatment of catheter-related infections is not part of the purpose of this article.

C3 glomerulonephritis is a rare disease defined by deposits of C3 on immunofluorescence due to dysregulation of the alternative pathway of the complement cascade. We present a case of a female patient that presented with nephrotic syndrome at the age of 18 due to C3 glomerulonephritis and progressed to end-stage renal disease after 9 years. She lost the first kidney graft on the third day after transplantation due to vascular thrombosis. A second kidney transplant was performed when the patient was 30 years old. C3 glomerulonephritis recurred on the kidney graft and the patient returned to dialysis 10 years after the transplant. Study of the alternative complement pathway revealed anti-factor H antibodies. She is currently on evaluation for a third kidney transplant and there is no consensus on the best treatment strategy. We present the literature available for treatment of C3 glomerulonephritis and the therapeutic options for this patient

Introdução: Desde que foi identificado, o vírus da hepatite C tem sido implicado na fisiopatologia de diversas doenças linfoproliferativas do tipo B, nomeadamente na criogloblulinemia mista. Caso clínico: Descrevemos o cas crioglobulinemia mista com envolvimento renal, apesar de prévia erradicação do VHC. Discussão: Revemos casos similares descritos na literatura, assim como a fisiopatologia e tratamento desta entidade clínica.

Introduction: Since its identification, hepatitis C virus infection has been implicated in the pathogenesis of several B cell disorders, specifically mixed cryoglobulinemia. Case Report: The authors describe the case of a 41-year-old male, who developed a mixed cryoglobulinemia vasculitis with renal involvement, several years after successful eradication of HCV with interferon therapy. discussion: Similar cases described in the literature are reviewed in this report. Possible explanations for the physiopathology of the disease and its implications in therapy are commented.