Acute kidney injury associated with dengue virus infection: a review / Injúria renal aguda associada à infecção pelo vírus da dengue: uma revisão

Abstract Acute kidney injury (AKI) is one of the least studied complications of dengue, but it carries high mortality rates and prolonged hospital stay. Due to the severity of this complication, the risk of developing chronic kidney disease (CKD) and the increasing number of dengue cases reported worldwide, particularly in the tropical and subtropical regions of Africa, Southeast Asia and South America, including Brazil, we embarked on this narrative review, aimed to update the epidemiology of AKI associated with dengue, elucidate the main pathophysiological mechanisms of AKI caused by the dengue virus infection, as well as discuss useful information on the prevention and management of AKI in patients with dengue.

Resumo A injúria renal aguda (IRA) é uma das complicações da dengue menos estudadas, mas que acarreta altas taxas de mortalidade e prolongamento do tempo de internação. Devido à gravidade dessa complicação, ao risco de desenvolvimento de doença renal crônica (DRC) e ao número crescente de casos de dengue relatados no mundo, particularmente nas regiões tropicais e subtropicais da África, Sudeste Asiático e América do Sul, incluindo o Brasil, foi proposta esta revisão narrativa que objetivou atualizar a epidemiologia da IRA associada à dengue, elucidar os principais mecanismos fisiopatológicos da IRA causada pela infecção do vírus da dengue, assim como discutir informações úteis sobre a prevenção e o manejo da IRA em pacientes com dengue.

Helicobacter pylori eradication in renal transplant candidates / Erradicação do Helicobacter pylori em candidatos a transplante renal

Abstract Introduction: Treatment for Helicobacter pylori (H. pylori) infection is recommended in transplant candidates due to the association between this infection and gastrointestinal disorders, which could significantly increase morbidity after renal transplantation with the use of immunosuppression. The objective of this study was to analyze the rate of eradication of H. pylori after antimicrobial treatment in chronic kidney disease patients who are candidates for kidney transplantation. Methods: A multicenter prospective cohort study was conducted. All adult chronic kidney disease patients seen at our institution were included. In the pre-transplantation evaluation, 83 patients underwent an upper gastrointestinal endoscopy with 2 diagnostic methods to detect H. pylori: histology and the rapid urease test. In total, 33 patients with H. pylori infection received treatment with 20 mg omeprazole, 500 mg amoxicillin, and 500 mg clarithromycin once daily for 14 days. Another upper gastrointestinal endoscopy was performed 8 to 12 weeks after the end of treatment to check for healing. Results: The study showed a prevalence of H. pylori in 51 (61.4%) patients. Histology was positive in 50 (98%) patients and the rapid urease test was positive in 31 (60.8%). The infection eradication rate was 48.5% (16 patients). Conclusions: There was a high prevalence rate of H. pylori and a low eradication rate after the long-term antimicrobial triple scheme used. The association of the rapid urease test with gastric mucosa histology did not increase the detection rate of H. pylori.

Resumo Introdução: Recomenda-se o tratamento da infecção por Helicobacter pylori (H. pylori) nos candidatos a transplante devido à associação entre esta infecção e distúrbios gastrointestinais, que podem aumentar significativamente a morbidade após transplante renal com o uso de imunossupressão. O objetivo deste estudo foi analisar a taxa de erradicação do H. pylori após tratamento antimicrobiano em pacientes com doença renal crônica, candidatos a transplante renal. Métodos: Realizou-se um estudo de coorte prospectivo multicêntrico. Incluímos todos os pacientes adultos com doença renal crônica atendidos em nossa instituição. Na avaliação pré-transplante, 83 pacientes foram submetidos a uma endoscopia digestiva alta com 2 métodos diagnósticos para detecção do H. pylori: histologia e teste rápido de urease. No total, 33 pacientes com infecção por H. pylori receberam tratamento com 20 mg de omeprazol, 500 mg de amoxicilina e 500 mg de claritromicina uma vez ao dia durante 14 dias. Outra endoscopia digestiva alta foi realizada 8 a 12 semanas após o término do tratamento para verificação da resposta. Resultados: O estudo mostrou prevalência de H. pylori em 51 (61,4%) pacientes. A histologia foi positiva em 50 (98%) pacientes e o teste rápido de urease foi positivo em 31 (60,8%). A taxa de erradicação da infecção foi 48,5% (16 pacientes). Conclusões: Após o esquema triplo antimicrobiano de longo prazo utilizado, houve uma alta taxa de prevalência de H. pylori e baixa taxa de erradicação. A associação do teste rápido de urease com a histologia da mucosa gástrica não aumentou a taxa de detecção do H. pylori.

Acute kidney injury associated with dengue virus infection: a review.

Acute kidney injury (AKI) is one of the least studied complications of dengue, but it carries high mortality rates and prolonged hospital stay. Due to the severity of this complication, the risk of developing chronic kidney disease (CKD) and the increasing number of dengue cases reported worldwide, particularly in the tropical and subtropical regions of Africa, Southeast Asia and South America, including Brazil, we embarked on this narrative review, aimed to update the epidemiology of AKI associated with dengue, elucidate the main pathophysiological mechanisms of AKI caused by the dengue virus infection, as well as discuss useful information on the prevention and management of AKI in patients with dengue.

Helicobacter pylori eradication in renal transplant candidates.

INTRODUCTION: Treatment for Helicobacter pylori (H. pylori) infection is recommended in transplant candidates due to the association between this infection and gastrointestinal disorders, which could significantly increase morbidity after renal transplantation with the use of immunosuppression. The objective of this study was to analyze the rate of eradication of H. pylori after antimicrobial treatment in chronic kidney disease patients who are candidates for kidney transplantation. METHODS: A multicenter prospective cohort study was conducted. All adult chronic kidney disease patients seen at our institution were included. In the pre-transplantation evaluation, 83 patients underwent an upper gastrointestinal endoscopy with 2 diagnostic methods to detect H. pylori: histology and the rapid urease test. In total, 33 patients with H. pylori infection received treatment with 20 mg omeprazole, 500 mg amoxicillin, and 500 mg clarithromycin once daily for 14 days. Another upper gastrointestinal endoscopy was performed 8 to 12 weeks after the end of treatment to check for healing. RESULTS: The study showed a prevalence of H. pylori in 51 (61.4%) patients. Histology was positive in 50 (98%) patients and the rapid urease test was positive in 31 (60.8%). The infection eradication rate was 48.5% (16 patients). CONCLUSIONS: There was a high prevalence rate of H. pylori and a low eradication rate after the long-term antimicrobial triple scheme used. The association of the rapid urease test with gastric mucosa histology did not increase the detection rate of H. pylori.

Effect of Dialyzer Reuse on the Activity of Paraoxonase 1 in Patients on Hemodialysis.

Background: Cardiovascular disease is the major cause of mortality in patients undergoing chronic hemodialysis treatment. The oxidative modification of low-density lipoprotein is a crucial step in the pathogenesis of atherosclerosis. Paraoxonase 1 (PON1) is the protein responsible for most of the antioxidant activity of high-density lipoprotein, and its reduced levels are associated with more cardiovascular events in several populations. In hemodialysis patients, reduced PON1 activity has been shown to be associated with increased cardiovascular mortality. Studies have shown that after the hemodialysis session, the activity of PON1 increases. The influence of dialyzer reuse on the activity of PON1 is unknown. We aimed to evaluate the effect of the reuse of two types of dialyzers (polynephron and polyethersulfone) on the PON1 activity of hemodialysis patients. Subjects and Methods: A total of 30 patients on hemodialysis were included. Pre- and post-dialysis blood samples were collected to analyze the activity of PON1 in thefirst use of the dialyzer and in the hemodialysis session of its sixth reuse. This process was carried out with polynephron (bisphenol-free) and polyethersulfone dialyzers. Results: We found that post-dialysis PON1 activity was significantly higher than pre-dialysis activity in both thefirst use and sixth reuse (P < 0.001). Conclusion: The practice of reusing the dialyzer did not interfere with the improvement of PON1 activity after the hemodialysis session.

Increased oxidative stress in foam cells obtained from hemodialysis patients.

Premature atherosclerosis represents the main cause of mortality among end-stage renal disease patients (ESRD). Increased inflammation and oxidative stress are involved in initiation and progression of the atherosclerotic plaque. As foam cells are capable of producing significant amounts of inflammatory mediators and free radicals, we hypothesized that foam cells from uremic patients could produce more inflammation and oxidative stress than foam cells from normal people and be, somehow, involved in the accelerated atherosclerosis of uremia. To test this hypothesis, the levels of a few markers of inflammation and oxidative stress: Tumor necrosis factor-α, inducible nitric oxide synthase, malondialdehyde, nitric oxide by-products were measured in the supernatants of macrophage-derived foam cells cultures from 18 hemodialysis patients and 18 apparently healthy individuals controls. Malondialdehyde levels in the supernatant of cell cultures (macrophages stimulated or not with native and oxidized lipoprotein) were significantly increased in uremic patients; no statistically significant difference was found between the supernatant concentrations of nitric oxide by-products, inducible nitric oxide synthase activity, and tumor necrosis factor-α between patients and controls. Our results, obtained with human macrophages and macrophage-derived foam cells, are compatible with the theory that increased cellular oxidative stress and inflammatory activity in ESRD patients could accelerate the atherosclerotic process. The present culture protocol showed it is possible to use human mononuclear cells to evaluate the oxidative metabolism of foam cells, which are considered to be the initial step of atherosclerotic lesions.

[Effects of ramipril and simvastatin on the oxidative stress of diabetic rats]. / Efeito do ramipril e da sinvastatina sobre o estresse oxidativo de ratos diabéticos.

OBJECTIVE: To evaluate if ramipril, with or without simultaneous use of simvastatin, would be capable of reducing oxidative stress of streptozotocin (STZ) induced diabetic rats. METHODS: The drugs were given to the diabetic rats for 2 weeks; oxidative stress was measured by dosage of total plasma antioxidant capacity (TRAP) and malondialdehyde (MDA). RESULTS: Ramipril, used alone, was capable of significantly increasing the antioxidative defenses of the diabetic rat; simvastatin, given alone or combined with ramipril in separate administrations, did not produce any significant effect on the oxidative stress; concomitant administration of ramipril and simvastatin significantly reduced the antioxidative plasmatic defenses of rats with chemically induced diabetes mellitus CONCLUSIONS: Our data corroborate the positive effect of ramipril upon plasma antioxidative defenses but did not confirm a possible beneficial effect of simvastatin in the model. More research is needed to clarify the paradoxal TRAP reduction verified with simultaneous administration of the drugs.

Efeito do ramipril e da sinvastatina sobre o estresse oxidativo de ratos diabéticos / Effects of ramipril and simvastatin on the oxidative stress of diabetic rats

OBJETIVO: Avaliar se o ramipril, isoladamente ou em combinação com a sinvastatina, seria capaz de reduzir o estresse oxidativo de ratos diabéticos pela estreptozotocina (STZ). MÉTODOS: As drogas foram administradas a ratos diabéticos por duas semanas; o estresse oxidativo foi medido por dosagem de capacidade antioxidante total plasmática (TRAP) e malonaldeído (MDA). RESULTADOS: O ramipril usado isoladamente foi capaz de aumentar significativamente as defesas antioxidantes do rato diabético; a sinvastatina isoladamente ou combinada ao ramipril em tomadas separadas não produziu efeito significativo sobre o estresse oxidativo; a administração simultânea de ramipril e sinvastatina reduziu as defesas antioxidantes plasmáticas de ratos com diabetes melito químico. CONCLUSÕES: Os dados do presente estudo corroboram o efeito positivo do ramipril sobre a defesa antioxidante do plasma, mas não confirmam um possível efeito benéfico da sinvastatina no modelo. Pesquisas adicionais são necessárias para clarificar a paradoxal redução da TRAP verificada pela administração simultânea das drogas.

OBJECTIVE: To evaluate if ramipril, with or without simultaneous use of simvastatin, would be capable of reducing oxidative stress of streptozotocin (STZ) induced diabetic rats. METHODS: The drugs were given to the diabetic rats for 2 weeks; oxidative stress was measured by dosage of total plasma antioxidant capacity (TRAP) and malondialdehyde (MDA). RESULTS: Ramipril, used alone, was capable of significantly increasing the antioxidative defenses of the diabetic rat; simvastatin, given alone or combined with ramipril in separate administrations, did not produce any significant effect on the oxidative stress; concomitant administration of ramipril and simvastatin significantly reduced the antioxidative plasmatic defenses of rats with chemically induced diabetes mellitus CONCLUSIONS: Our data corroborate the positive effect of ramipril upon plasma antioxidative defenses but did not confirm a possible beneficial effect of simvastatin in the model. More research is needed to clarify the paradoxal TRAP reduction verified with simultaneous administration of the drugs.

[Increase in prevalence of diabetes mellitus as a cause of dialytic end-stage renal disease: analysis of 20 years in the west region of Paraná]. / Aumento na prevalência de diabete melito como causa de insuficiência renal crônica dialítica: Análise de 20 anos na região Oeste do Paraná.

UNLABELLED: Diabetic nephropathy (DN) is the main cause of chronic kidney disease (CKD) in developed countries. OBJECTIVE: To observe if there was an increase in the prevalence of diabetes mellitus (DM) of CKD in the last 20 years and to analyze comparatively the survival on dialysis of diabetic and non-diabetic patients. METHODS: Retrospective analysis of patients kept on dialysis in the west region of Paraná State in the period between 1985-2005. Survival analysis was performed using Kaplan-Meier Curves. RESULTS: In the period, 645 patients were admitted to dialysis. In 16.1% DM was the cause of the CKD. It was observed a progressive increase in the prevalence of DM as a cause of CKD. Patient survival was lower in diabetics. CONCLUSIONS: The prevalence of DM as a cause of CKD increased in the last 20 years in our region. The survival rates were lower in diabetic than in non-diabetic patients.

Aumento na prevalência de diabete melito como causa de insuficiência renal crônica dialítica: análise de 20 anos na região Oeste do Paraná / Increase in prevalence of diabetes mellitus as a cause of dialytic end-stage renal disease: analysis of 20 years in the west region of Paraná

A nefropatia diabética (ND) é a principal causa de insuficiência renal crônica terminal (IRCT) nos países desenvolvidos. OBJETIVOS: Observar se ocorreu aumento da prevalência de diabete melito (DM) como causa de IRCT nos últimos 20 anos e comparar a sobrevida em diálise dos diabéticos e não diabéticos. MÉTODOS: Análise retrospectiva dos pacientes mantidos em diálise na região Oeste do Paraná no período de 1985 a 2005. A estimativa de sobrevida foi realizada pela Curva de Sobrevida de Kaplan-Meier. RESULTADOS: Durante este período, foram admitidos em diálise 645 pacientes. Em 16,1 por cento deles o DM foi a causa da IRCT. Observou-se aumento na prevalência de DM como causa de IRCT. A sobrevida dos pacientes em diálise foi inferior nos diabéticos. CONCLUSÕES: A prevalência de DM como causa de IRCT aumentou progressivamente nos últimos 20 anos em nossa região. A sobrevida de pacientes diabéticos em diálise foi menor que a dos não-diabéticos.

Diabetic nephropathy (DN) is the main cause of chronic kidney disease (CKD) in developed countries. OBJECTIVE: To observe if there was an increase in the prevalence of diabetes mellitus (DM) of CKD in the last 20 years and to analyze comparatively the survival on dialysis of diabetic and non-diabetic patients. METHODS: Retrospective analysis of patients kept on dialysis in the west region of Paraná State in the period between 1985­2005. Survival analysis was performed using Kaplan-Meier Curves. RESULTS: In the period, 645 patients were admitted to dialysis. In 16.1 percent DM was the cause of the CKD. It was observed a progressive increase in the prevalence of DM as a cause of CKD. Patient survival was lower in diabetics. CONCLUSIONS: The prevalence of DM as a cause of CKD increased in the last 20 years in our region. The survival rates were lower in diabetic than in non-diabetic patients.

Transplante de pâncreas e de ilhotas pancreáticas: visäo de nefrologista / Pancreas and pancreatic islet cell transplantation: a Nephrologist's viewpoint

Os autores, após dimensionarem o problema do diabetes mellitus e da nefropatia diabética no Brasil e no mundo, fazem uma revisäo, sob a ótica do nefrologista, sobre transplante de pâncreas e de ilhotas pancreáticas, centrada nos riscos e benefícios do transplante combinado de pâncreas e rim (TCPR) para o diabético urêmico. No texto é ressaltada a importância da colaboraçäo entre o endocrinologista e o nefrologista para melhorar a sobrevida dos diabéticos com nefropatia e para uma definiçäo local sobre a viabilidade e validade do estabelecimento de um programa de TCPR.

Diabetes mellitus induzido por estreptozotocina: comparaçäo em longo prazo entre duas vias de administraçäo / Streptozotocin-induced diabetes mellitus: long-term comparison of two drug administration routes

O objetivo é avaliar em longo prazo, em ratos, a severidade e a duraçäo do diabetes mellitus induzido pela administraçäo de estreptozotocina (STZ) intraperitoneal e por dois sítios endovenosos (sublingual e caudal). Foram estudados quatro grupo de 10 ratos Wistar-Furth isogênicos. Um grupo de animais näo recebeu STZ (controle). STZ mg/kg foi injetada no peritônio, na veia sublingual e na veia da cauda, para a formaçäo dos outros três grupos de estudo. Pesos e glicemias foram documentados no dia da injeçäo da droga e em uma, duas, seis, oito, 20, 30 e 40 semanas após. Näo houve aparecimento de diabetes espontâneo no grupo-controle. Independentemente da via utilizada para administrtaçäo, a severidade e a duraçäo do diabetes induzido pela STZ foram semelhantes entre os grupos de estudo. Houve, no entanto, 30 porcento de falha da STZ quando ela foi dada intraperitonealmente; 10 porcento dos animais que receberam STZ em uma veia caudal e 30 porcento dos que a receberam em uma veia sublingual morreram precocemente por toxicidade. Na dose escolhida, e por qualquer uma das vias utilizadas, STZ promoveu diabetes mellitus severo e de longa duraçäo. Para alcançar a dose diabetogênica, sua injeçäo em uma das veias da cauda mostrou-se a mais conveniente.(au)

Relato de caso: nefropatia membranosa e psoríase vulgar - a propósito de dois casos / Relate the cases: membranous nephropathy and vulgar psoriasis

Embora näo freqüentemente, associaçäo entre psoríase vulgar e nefropatia membranosa tem sido relatada, sendo um mecanismo auto-imune comum sugerido como a origem desta associaçäo. Apresetam-se os casos de 2 pacientes portadores de psoríase vulgar que desenvolveram nefropatia membranosa durante o curso da dermatose e que, apesar das terapêuticas utilizadas, evoluiram para insuficiência renal crönica terminal. Estes säo, provavelmente, os primeiros casos descritos desta associçäo no país (au)

Nefropatia crônica do alotransplante renal: fatores co-mórbidos / Chronic nephropathies in renal allotransplantation

Foram revisados 372 casos de transplantes renais primários realizados entre junho de 1973 e dezembro de 1992 em dois hospitais de Londrina (Evangélico e Universitário), com o objetivo de verificar a influência de crises de rejeiçäo aguda e de outros fatores co-mórbidos na evoluçäo do processos de perda crônica do aloenxerto. A exclusäo englobou todos os casos com menos de 6 meses de evoluçäo, as perdas renais por rejeiçäo irreversível, aqueles casos de recorrência da doença original e os casos de documentada nefrotoxicidade por ciclosporina. Os transplantes foram analisados de acordo com o esquema de imunossupressäo utilizado em grupo azatioprina-prednisona ou grupo tríplice com azatioprina, prednisona e ciclosporina, recorrendo-se à regressäo logística multivariável para estimar o risco de desenvolvimento de nefropatia crônica do aloenxerto em relaçäo a episódios de rejeiçäo aguda, de ocorrência de insuficiência renal aguda (IRA) pós-operatória imediata, do sexo e da idade dos receptores, da compatibilidade HLA e do tipo de doador renal. Em ambos os protocolos verificamos nítida correlaçäo entre presença e severidade da rejeiçäo aguda e risco de evoluçäo desfavorável para disfunçäo crônica do enxerto; do mesmo modo, os receptores jovens com idade < de 20 anos, aqueles que tiveram seu curso inicial complicado por IRA e os que receberam rins näo idênticos pela tipagem HLA estiveram com maior associaçäo à evoluçäo para nefropatia crônica. A adiçäo de ciclosporina para constituir o esquema imunodepressor tríplice melhorou o resultado do grupo de indivíduos jovens, porém se mostrou adversa se prescrita em concomitância com a necessidade de diálise pós-operatória imediata.