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Dive into the research topics where Roberto José de Carvalho-Filho is active.

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Featured researches published by Roberto José de Carvalho-Filho.


Liver International | 2006

Efficacy and tolerance of interferon-alpha in the treatment of chronic Hepatitis C in end-stage renal disease patients on hemodialysis

Cristina M. Rocha; Renata M. Perez; Adalgisa P. Ferreira; Roberto José de Carvalho-Filho; Fábio Heleno de Lima Pace; I. Silva; José Osmar Medina Pestana; Valéria Pereira Lanzoni; Antonio Eduardo Benedito Silva; Maria Lucia G. Ferraz

Abstract: Background: Patients with end‐stage renal disease (ESRD) show a high prevalence of hepatitis C, with a negative impact on the survival on hemodialysis and after renal transplantation. We evaluated the efficacy and tolerance of interferon‐α (IFN‐α) in HCV‐infected ESRD patients on dialysis.


Liver International | 2008

Optimized cutoffs improve performance of the aspartate aminotransferase to platelet ratio index for predicting significant liver fibrosis in human immunodeficiency virus/hepatitis C virus co‐infection

Roberto José de Carvalho-Filho; Leonardo de Lucca Schiavon; Janaína Luz Narciso-Schiavon; Juliana P. Sampaio; Valéria Pereira Lanzoni; Maria Lucia G. Ferraz; Antonio Eduardo Benedito Silva

Aim: To assess the diagnostic value of modified cutoffs for aspartate aminotransferase to platelet ratio index (APRI) to predict significant liver fibrosis in human immunodeficiency virus (HIV)/hepatitis C virus (HCV) patients.


Journal of Viral Hepatitis | 2013

The presence of resistance mutations to protease and polymerase inhibitors in Hepatitis C virus sequences from the Los Alamos databank

Rayanne Santos Alves; Artur Trancoso Lopo de Queiroz; Mario G. Pessoa; E. F. da Silva; Daniel Ferraz de Campos Mazo; Flair José Carrilho; Roberto José de Carvalho-Filho; I. M. V. G. de Carvalho

Several new direct‐acting antiviral (DAA) drugs are in development for chronic hepatitis C viral (HCV) infection, and NS3‐NS4A serine protease and the NS5B RNA‐dependent RNA polymerase have been the major targets. HCV variants displaying drug‐resistant phenotypes have been observed both in vitro and during clinical trials. Our aim was to characterize amino acid changes at positions previously associated with resistance in protease (NS3) and polymerase (NS5B) regions from treatment‐naïve HCV patients infected with genotypes 1a, 1b and 3a. All 1383 NS3 protease sequences (genotype 1a = 680, 1b = 498 and 3a = 205) and 806 NS5B polymerase sequences (genotypes 1a = 471, 1b = 329, 3a = 6) were collected from Los Alamos databank. Genotype 3a protease sequences showed the typical low‐level resistance mutation V36L. NS3 sequences from other genotypes presented mutations on positions 36, 39, 41, 43, 54, 80, 109, 155 and 168 in a frequency lower than 2%, except for the mutation Q80R found in 35% of genotype 1a isolates. Polymerase sequences from genotype 3a patients showed five typical mutations: L419I, I424V, I482L, V499A and S556G. Two positions presented high polymorphism in the NS5B region from genotype 1a (V499A) and genotype 1b (C316N) subjects. Our results demonstrated a natural profile of genotype 3a that can be associated with the pre‐existence of HCV variants resistant to first‐generation protease inhibitors and to non‐nucleoside polymerase inhibitors. Likewise, genotype 1b isolates and genotype 1a sequences exhibited pre‐existing mutations associated with resistance to Palm II and Thumb I polymerase inhibitors, respectively.


World Journal of Gastroenterology | 2014

Non-invasive diagnosis of liver fibrosis in chronic hepatitis C

Leonardo de Lucca Schiavon; Janaína Luz Narciso-Schiavon; Roberto José de Carvalho-Filho

Assessment of liver fibrosis in chronic hepatitis C virus (HCV) infection is considered a relevant part of patient care and key for decision making. Although liver biopsy has been considered the gold standard for staging liver fibrosis, it is an invasive technique and subject to sampling errors and significant intra- and inter-observer variability. Over the last decade, several noninvasive markers were proposed for liver fibrosis diagnosis in chronic HCV infection, with variable performance. Besides the clear advantage of being noninvasive, a more objective interpretation of test results may overcome the mentioned intra- and inter-observer variability of liver biopsy. In addition, these tests can theoretically offer a more accurate view of fibrogenic events occurring in the entire liver with the advantage of providing frequent fibrosis evaluation without additional risk. However, in general, these tests show low accuracy in discriminating between intermediate stages of fibrosis and may be influenced by several hepatic and extra-hepatic conditions. These methods are either serum markers (usually combined in a mathematical model) or imaging modalities that can be used separately or combined in algorithms to improve accuracy. In this review we will discuss the different noninvasive methods that are currently available for the evaluation of liver fibrosis in chronic hepatitis C, their advantages, limitations and application in clinical practice.


Revista Da Sociedade Brasileira De Medicina Tropical | 2010

Gender influence on treatment of chronic hepatitis C genotype 1

Janaína Luz Narciso-Schiavon; Leonardo de Lucca Schiavon; Roberto José de Carvalho-Filho; Juliana P. Sampaio; Philipe Nicolas El Batah; Denize Vieira Barbosa; Maria Lucia Cardoso Gomes Ferraz; Antonio Eduardo Benedito Silva

INTRODUCTION Although various studies have been published regarding the treatment of chronic hepatitis C (CHC) with peginterferon (Peg-IFN) and ribavirin, little is known regarding the real impact of gender on the characteristics that influence the effectiveness and safety of antiviral treatment for CHC patients. The objective of this study was to evaluate the influence of gender on HCV treatment outcomes. METHODS A retrospective analytical study was conducted among selected carriers of CHC genotype 1, who were treated with Peg-IFN alpha-2b at a dose of 1.5 microg/kg or Peg-IFN alpha-2a at a dose of 180 microg/week plus a ribavirin dose of 1,000-1,250 mg/day, according to weight, between 2001 and 2007. RESULTS Among 181 patients undergoing treatment, the mean age was 46.4 +/- 11.0 years and 46% were women. At baseline, 32% of the patients had advanced fibrosis (F3-F4 Scheuer), and 83% of the subjects had viral load > 400,000 IU/ml, without significant difference between the genders (p = 0.428 and p = 0.452, respectively). When compared with men, women had higher incidence of many adverse events such as anemia (p < 0.001) and higher need for dose reduction, for both Peg-IFN (p = 0.004) and ribavirin (p = 0.006). However, the rate of sustained virological response (SVR) did not differ between the genders: 45% (female) vs 41% (male); p=0.464. CONCLUSIONS This study suggests that women and men react differently to combined therapy, especially in relation to the incidence of adverse events and the need for dose modification. Nevertheless, these differences do not influence the SVR rate.


World Journal of Gastroenterology | 2015

Management of hepatitis C in patients with chronic kidney disease

Roberto José de Carvalho-Filho; Ana Cristina Ca Feldner; Antonio Eduardo Benedito Silva; Maria Lucia G. Ferraz

Hepatitis C virus (HCV) infection is highly prevalent among chronic kidney disease (CKD) subjects under hemodialysis and in kidney transplantation (KT) recipients, being an important cause of morbidity and mortality in these patients. The vast majority of HCV chronic infections in the hemodialysis setting are currently attributable to nosocomial transmission. Acute and chronic hepatitis C exhibits distinct clinical and laboratorial features, which can impact on management and treatment decisions. In hemodialysis subjects, acute infections are usually asymptomatic and anicteric; since spontaneous viral clearance is very uncommon in this context, acute infections should be treated as soon as possible. In KT recipients, the occurrence of acute hepatitis C can have a more severe course, with a rapid progression of liver fibrosis. In these patients, it is recommended to use pegylated interferon (PEG-IFN) in combination with ribavirin, with doses adjusted according to estimated glomerular filtration rate. There is no evidence suggesting that chronic hepatitis C exhibits a more aggressive course in CKD subjects under conservative management. In these subjects, indication of treatment with PEG-IFN plus ribavirin relies on the CKD stage, rate of progression of renal dysfunction and the possibility of a preemptive transplant. HCV infection has been associated with both liver disease-related deaths and cardiovascular mortality in hemodialysis patients. Among those individuals, low HCV viral loads and the phenomenon of intermittent HCV viremia are often observed, and sequential HCV RNA monitoring is needed. Despite the poor tolerability and suboptimal efficacy of antiviral therapy in CKD patients, many patients can achieve sustained virological response, which improve patient and graft outcomes. Hepatitis C eradication before KT theoretically improves survival and reduces the occurrence of chronic graft nephropathy, de novo glomerulonephritis and post-transplant diabetes mellitus.


Gut | 2011

Transient elastography in chronic viral hepatitis: a critical appraisal

Ana-Carolina Cardoso; Roberto José de Carvalho-Filho; Patrick Marcellin

Even with all the heated discussion about the value of liver biopsy, it remains the gold standard method for the assessment of liver fibrosis and the severity of chronic liver diseases.1 Histological analysis of liver tissue still provides invaluable information about three key issues for the management of patients with liver diseases: diagnosis, prognosis and therapeutic decisions. In the context of chronic infection with hepatitis C virus (HCV) or hepatitis B virus (HBV), evaluation of the stage of liver fibrosis is of major importance. Additional information can also be provided, such as the pattern of liver fibrosis, grading of necroinflammatory activity and the presence of steatosis and hepatic iron overload. These and other histological findings are highly relevant in clinical practice, because they not only allow the clinician to infer on the dynamics of fibrogenesis (whether lesions are ancient or progressive), but also permit the identification of associated liver diseases that can potentially alter the natural history of chronic viral hepatitis and impair the efficacy of therapy. Nevertheless, liver biopsy is a costly and invasive technique with associated mortality and morbidity, well documented in both retrospective and prospective studies.2 3 A typical biopsy fragment represents only 1/50 000 of the organ and most chronic liver diseases exhibit a heterogeneous distribution of hepatic fibrosis. Therefore, histopathological analysis of liver tissue is susceptible to variability in interpretation, being significantly influenced by the quality of the fragment (adequate length and number of portal tracts) and by the expertise of the pathologist.4 5 In a world with an imperfect gold standard model, several non-invasive approaches have been proposed to estimate liver fibrosis in patients with liver diseases, …


Scandinavian Journal of Gastroenterology | 2010

YKL-40 and hyaluronic acid (HA) as noninvasive markers of liver fibrosis in kidney transplant patients with HCV chronic infection.

Leonardo de Lucca Schiavon; Roberto José de Carvalho-Filho; Janaína Luz Narciso-Schiavon; Jose O. Medina-Pestana; Valéria Pereira Lanzoni; Maria Lucia G. Ferraz; Antonio Eduardo Benedito Silva

Abstract Objective. Hepatitis C is highly prevalent among kidney transplant (KT) recipients. In this population, the natural history of hepatitis C virus (HCV) infection and its proper management remains controversial. The invasiveness of the procedure and the interpretation variability of liver biopsy limit its use in these patients. We sought to evaluate the performance of YKL-40 and HA as markers of liver fibrosis in KT patients with HCV infection. Material and methods. This cross-sectional study included HCV infected KT individuals. Univariate analysis was used to identify variables associated with significant fibrosis (METAVIR ≥ F2). The diagnostic values of the YKL-40 and HA were compared using receiver operating characteristic (ROC) curves. Results. Eighty-five patients were included (60% males, mean age 44.9 ± 9.4 years). Significant fibrosis was observed in 14 patients (17%). When compared to F0/F1 individuals, patients with significant fibrosis were older, showed a higher time since transplantation, and higher prevalence of diabetes. No difference was observed in YKL-40 levels between the groups. Significantly higher levels of HA were noted in METAVIR ≥ F2 subjects (108 vs. 37 ng/ml, p = 0.002). The AUROCs of YKL-40 and HA for predicting significant fibrosis were 0.615 and 0.765, respectively (p = 0.144). Levels of YKL-40 ≤ 105 ng/ml and of HA ≤ 27 ng/ml showed a NPV of 36% and 96%, respectively. YKL-40 ≥ 418 ng/ml and HA ≥ 120 ng/ml exhibited a PPV of 31% and 39%, respectively. Conclusions. Increased serum levels of HA but not of YKL-40 were associated with more advanced stages of liver fibrosis in KT HCV-infected patients.


World Journal of Gastroenterology | 2012

Central nervous system vasculitis and polyneuropathy as first manifestations of hepatitis C

Roberto José de Carvalho-Filho; Janaína Luz Narciso-Schiavon; Luciano Henrique Lenz Tolentino; Leonardo de Lucca Schiavon; Maria Lucia G. Ferraz; Antonio Eduardo Benedito Silva

Sensory or motor peripheral neuropathy may be observed in a significant proportion of hepatitis C virus (HCV)-infected patients. However, central nervous system (CNS) involvement is uncommon, especially in cryoglobulin-negative subjects. We describe a case of peripheral neuropathy combined with an ischemic CNS event as primary manifestations of chronic HCV infection without cryoglobulinemia. Significant improvement was observed after antiviral therapy. We discuss the spectrum of neurological manifestations of HCV infection and review the literature.


Liver International | 2009

Clinical and histological impact of previous hepatitis B virus infection in patients with chronic hepatitis C

Roberto José de Carvalho-Filho; Leonardo de Lucca Schiavon; Janaína Luz Narciso-Schiavon; Juliana P. Sampaio; Valéria Pereira Lanzoni; Maria Lucia G. Ferraz; Antonio Eduardo Benedito Silva

Background: Recent reports suggest that hepatitis C virus (HCV) carriers with serological markers of prior hepatitis B virus (HBV) infection have more advanced liver fibrosis, irrespective of HBV‐DNA detection.

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Maria Lucia G. Ferraz

Federal University of São Paulo

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Valéria Pereira Lanzoni

Federal University of São Paulo

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I. Silva

Federal University of São Paulo

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Juliana P. Sampaio

Federal University of São Paulo

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Christini Takemi Emori

Federal University of São Paulo

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Renata M. Perez

Federal University of São Paulo

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