A predictive model of progressive chronic kidney disease in idiopathic nephrotic syndrome.

BACKGROUND: There are limited data on the risk factors for chronic kidney disease (CKD) in children with idiopathic nephrotic syndrome (INS). This retrospective cohort study aimed to develop a predictive model for CKD progression in children with INS. METHODS: Between 1970 and 2012, a total of 294 patients with INS were followed up. The primary outcome was progression to CKD stage 3 or higher. A predictive model was developed using a Cox proportional hazards model. A score was calculated using b-coefficients and summing up points assigned to each significant variable. Prognostic score was grouped into categories: low risk, medium risk, and high risk. RESULTS: Median follow-up was 6.9 years. Median renal survival was 26.1 years and probability of CKD stage 3 or higher was 8% in 10 years. Multivariate analysis showed that the most accurate model included initial age, hematuria, and steroid resistance. Accuracy was high with a c-statistic of 0.95 (95% confidence interval [CI] 0.91-0.99), 0.92 (95% CI 0.88-0.96), and 0.92 (95% CI 0.87-0.97) at 2, 5, and 10 years of follow-up respectively. By survival analysis, 10-year renal survival was 100% for the low-risk and 95% for the medium-risk group, while 40% of high-risk patients would exhibit CKD stage 3 or higher (P < 0.001). CONCLUSIONS: Our predictive model of CKD may contribute to the early identification of a subgroup of INS patients at a high risk of renal dysfunction.

Preditores para desenvolvimento de arritmia ventricular maligna na cardiopatia chagásica: protocolo de estudo caso-controle / Predictors for development of malignant ventricular arrhythmia in Chagas heart disease: case-control study protocol

Introdução: A doença de Chagas acomete três a quatro milhões de brasileiros. O curso clínico da doença é extremamente variável e aproximadamente um terço dos pacientes infectados desenvolve doença cardíaca potencialmente letal, incluindo arritmias ventriculares malignas e insuficiência cardíaca. Os mecanismos eletrofisiológicos mais frequentemente envolvidos na morte súbita nos chagásicos são representados pela taquicardia ventricular e fibrilação ventricular. Objetivo: Descrever protocolo de estudo que busca preditores da evolução para a morte por arritmia na doença de Chagas. Metodologia: Está sendo estudada a associação de arritmias malignas com marcadores relacionados à repolarização ventricular (microalternância de onda T e intervalo Tpeak a Tend - TpTe) e aqueles relacionados ao parasitismoe à inflamação, além dos marcadores clássicos de risco na cardiopatia chagásica. Trata-se de estudo do tipo caso-controle e a amostra estimada foi de 240 pacientes chagásicos, sendo 120 casos (arritmia ventricular) e 120 controles (sem arritmia ventricular). Esses pacientes são submetidos a: entrevista médica e exame físico; eletrocardiograma, com medida do intervalo TpTe na derivação V5; ecocardiograma, holter de 24h e teste ergométrico; dosagem de TNF, sTNFR1, sTNFR2, IL-6, MCP-1 e RANTES, BDNF, NT-proBNP e de PCR para Trypanosoma cruzi. Resultados e conclusões: O presente estudo pretende fornecer informações acerca da fisiopatologia e mecanismos patogenéticos das arritmias malignas nadoença de Chagas. A identificação de marcadores não invasivos de risco para morte súbita tornará possível a identificação de subgrupos que se beneficiam do implante de CDI.

Introduction: Chagas disease affects three to four million Brazilians. The clinical course of the disease is extremely variable, and about one third of infected patients develop life-threatening heart disease, including malignant ventricular arrhythmias and heart failure. The electrophysiological mechanisms most frequently associated with sudden death in Chagasdisease are represented by ventricular tachycardia and ventricular fibrillation. Objective: To study predictors of progression to death from arrhythmia in Chagas disease. Methodology : It is being studied the association of markers of malignant arrhythmias related to ventricularrepolarization ( micro - alternation of the T wave interval and Tpeak to Tend - TpTe ) and those related to parasitism and inflammation, in addition to the classical risk markers in Chagas heart disease. This is a case-control study and the sample was estimated at 240 chagasic patients, 120 cases (ventricular arrhythmias ) and 120 controls (without ventricular arrhythmias) These patients are being subjected to: medical interview and physical examination; Electrocardiogram, with measurement TpTe interval in lead V5; echocardiogram, Holter 24-hour stress test; determination of TNF sTNFR1, sTNFR2, IL-6, MCP -1 and RANTES, BDNF, NT -proBNP and PCR for Trypanosoma cruzi. Results and Conclusions: The present study aims to provide information about the pathophysiology and pathogenetic mechanisms of malignant arrhythmias in Chagas disease. The identification of non-invasive markers of risk for arrhythmic death will make possible toidentify patients who benefit from ICD implantation.