Hepatitis: Brazil

Dias JC. · Centro de Pesquisas René Rachou, Fundação Oswaldo CruzBelo Horizonte, MG, Brasil. · Rev Soc Bras Med Trop. · Pubmed #17119753 links to  free full text

Abstract: Experimental evidence and field observations concerning the oral transmission of Trypanosoma cruzi to human beings and mammalian species are reviewed, confirming its unquestionable occurrence, mainly in the enzootic cycle of the parasite. Several types of foods and carriers of the flagellate have been involved in this transmission route, where the human cases are generally related to infected triatomines and/or natural reservoirs in the proximities of the event. The penetration points of the parasite (mouth, esophagus, stomach and intestinal mucosae) are reviewed, as well as the general anatomic and pathological processes, such as hemorrhagic phenomena, mesenteritis and interstitial hepatitis. In particular, different aspects of the biology and biochemistry of the parasite are analyzed, especially in terms of its epidemiology and the possibilities of the prevention of the oral transmission of Chagas' disease.

Silva AS, Santos LL, Passos AD, Sankarankutty AK, Martinelli Ade L, Silva Ode C. · Department of Social Medicine, FMRP, USP, Brazil. · Acta Cir Bras. · Pubmed #17013520 links to  free full text

Abstract: Chronic liver disease is a considerable burden on society, being one of the three main causes of death in certain regions of Africa and Asia. Liver transplant is the only treatment option for cirrhosis, which is the end stage of many chronic liver diseases. This article reviews the preventable causes of cirrhosis and the preventive strategies which could be implemented in order to avoid the catastrophic consequences of cirrhosis. With small variations around the world, 70 to 80% of the end stage liver diseases are caused by excessive alcohol consumption and by viral hepatitis, both of which are potentially preventable. Excessive alcohol consumption has important public health consequences because of its involvement not only with cirrhosis, but also with motor vehicle accidents, unemployment, domestic violence etc. Among the viral causes, Hepatitis Virus B and C have the greatest impact on public health. Effective vaccine is available for Hepatitis Virus B and must be put in use. While a vaccine for Hepatitis Virus C is awaited, effective preventive strategies should be undertaken to avoid the preventable cases of end stage liver disease.

Martinelli Ade L, Teixeira AC, Souza FF, Sankarankutty AK, Silva Ode C. · Department of Medicine, FMRP, USP, Brazil. · Acta Cir Bras. · Pubmed #17013506 links to  free full text

Abstract: Hepatitis C is the main cause of cirrhosis and hepatocellular carcinoma and the leading indication of liver transplantation. The aim of this article was to review specific epidemiological, clinical and therapeutic aspects of hepatitis C and their implication for the hepatologists belonging to liver transplantation services. These specific aspects were reviewed in the literature mainly using Medline. Data regarding the epidemiological, clinical and therapeutic aspects of hepatitis C are discussed, with emphasis on their consequences for the liver transplantation team. Hepatitis C is a challenge for hepatologists and for the liver transplantation team. The burden we observe today is the late consequence of infection that occurred in the past. Measures for early recognition of complications of liver disease are recommended. HCV treatment should always be performed before liver transplantation if possible, but if not, HCV recurrence should be recognized and treated early after transplantation.

Strauss E, Dias Teixeira MC. · Department of Pathology, School of Medicine, University of São Paulo, SP, Brazil. · Liver Int. · Pubmed #16911456 No free full text.

Abstract: A number of different studies have shown a clear reduction in the quality of life of hepatitis C virus (HCV)-related liver-disease patients. Quality of life can be assessed by means of both generic and specific instruments, depending on the aim of the study and the population being studied. The application of a specific instrument to patients with liver diseases provides a broader assessment of different parameters related to hepatic disorders. In hepatitis C, alterations such as the stigma of liver disease, concerns about the disease and symptoms of the disease could be demonstrated with this type of instrument. The impact of the diagnosis of hepatitis C, a potentially serious disease, and the presence of comorbidities such as alcohol and drugs may lead to lower quality of life. Longitudinal studies have proved that, following diagnosis, the stigma of liver disease becomes more apparent over time. Women report worse quality of life than men, supporting that gender differences in hepatitis are also important when assessing quality of life. Alterations in the quality of life of patients submitted to treatment are mainly related to the somatic side effects of Interferon and Ribavirin and are most noticeable in the first weeks of therapy. Early improvement in the quality of life of patients who become HCV-RNA negative suggests that the virus itself plays a biological role. There is no doubt that liver transplantation leads to an improvement in quality of life. Nevertheless, a major concern is the relapse of HCV, with the associated lower quality of life.

Schinoni MI, Paraná R, Cavalcante D. · Edgard Santos University Hospital, Salvador, BA, Brazil. · Braz J Infect Dis. · Pubmed #16878263 links to  free full text

Abstract: Hepatitis C is a worldwide endemic disease, affecting roughly 200 million people. It has a variable prognosis, depending on the progression to fibrosis. During the last five years, the importance of apoptosis for the pathogenesis of various diseases, including hepatitis, has been recognized. It has been suggested that an increase in T cell-apoptosis during a hepatitis C virus infection is the cause of impaired regulation of the immune cellular response, helping to maintain infection. Thus, the interest in discovering the probable mechanisms by which the hepatitis C virus perpetuates in the liver, and to determine the conditions that predispose for progression of this disease, makes investigation of apoptosis in hepatic injury of great interest. We have made an overview of the various mechanisms by which the cell, more specifically the hepatic cell, is affected by apoptosis, and how it interacts with the hepatitis C virus and the immune system.

Alves C, Vieira N, Toralles MB, Lyra A. · Faculdade de Medicina, Universidade Federal da Bahia. · Acta Gastroenterol Latinoam. · Pubmed #16859082 No free full text.

Abstract: Genetic, immunological and environmental factors are involved in the pathogenesis of the gastrointestinal diseases. Situated on the short arm of the chromosome 6, the HLA system is very polymorphic and has the capacity to confer susceptibility or resistance to different diseases. The relationship HLA vs. disease differs with the disease and, sometimes, with the ethnic-racial group studied. Histocompatibility molecules could determine the age of onset, the treatment response and the clinical course for some diseases. The recent discovery of new methods to typify HLA alleles and the changes in its nomenclature has contributed to a better understanding of this system. Nevertheless, has not thoroughly widespread. The aim of this review is to discuss the HLA structure and function, methods of detection, nomenclature and its association with celiac disease, Crohn's disease, autoimmune hepatitis, autoimmune pancreatitis and oral recurrent ulcers.

Vitral CL, Gaspar AM, Souto FJ. · Departamento de Virologia, Instituto Oswaldo Cruz-Fiocruz, Av. Brasil 4365, 21040-900 Rio de Janeiro, RJ, Brasil. · Mem Inst Oswaldo Cruz. · Pubmed #16830702 No free full text.

Abstract: The prevalence of hepatitis A virus (HAV) infection is high in developing countries, in which low standards of sanitation promote the transmission of the virus. In Latin America, which is considered an area of high HAV endemicity, most HAV-positive individuals are infected in early childhood However recent studies have shown that prevalence rates are decreasing. Herein, we review the data on HAV prevalence and outbreaks available in scientific databases. We also use official government data in order to evaluate mortality rates in Brazil over the last two decades. Studies conducted in the northernmost regions of Brazil have indicated that, although improved hygiene has led to a reduction in childhood exposure to HAV, the greatest exposure still occurs early in life. In the Southeastern region, the persistence of circulating HAV has generated outbreaks among individuals of low socioeconomic status, despite adequate sanitation. Nationwide, hepatitis A mortality rates declined progressively from 1980 to 2002. During that period, mortality rates in the Northern region consistently exceeded the mean national rate and those for other regions. Excluding the North, the rates in all regions were comparable. Nevertheless, the trend toward decline observed in the South was paralleled by a similar trend in the North.

Ferreira CT, da Silveira TR. · Hospital de Clinicas de Porto Alegre, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil. · J Pediatr (Rio J). · Pubmed #16826313 links to  free full text

Abstract: OBJECTIVE: To present an updated review and criticism of viral hepatitis A and B prevention by immunization. SOURCES OF DATA: Review of medical articles obtained from the MEDLINE database. The most recent and representative articles on the subject (2000-2006) were selected. The Centers for Disease Control and Prevention (CDC), American Academy of Pediatrics (AAP), Brazilian Society of Pediatrics and Brazilian Ministry of Health websites were also researched. SUMMARY OF THE FINDINGS: Viral hepatitis prevention is an enormous challenge to the public health systems of countries and the medical and scientific communities. Hepatitis viruses produce important morbidity and mortality in the world, causing acute and chronic hepatic disease. There are highly efficient vaccines available on the market to prevent new infections by the A and B viruses. However, A and B viruses continue to be among the most commonly notified diseases preventable by vaccines. In this article, we discuss the vaccines used to prevent these infections, with the aim of expanding knowledge and the practice of prevention of these infectious diseases. CONCLUSIONS: Although the vaccines against A and B hepatitis are recommended for various risk groups, estimated vaccine coverage is still modest and many vaccination opportunities are lost. In order to reduce the incidence of A and B hepatitis, which are preventable by vaccines, it is necessary for physicians to encourage their patients to be vaccinated.

Feijó RB, Cunha J, Krebs LS. · Faculdade de Medicina, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil. · J Pediatr (Rio J). · Pubmed #16826311 links to  free full text

Abstract: OBJECTIVES: To present the criteria used to define a vaccination schedule for childhood and adolescence, comparing the recommendations of national and international excellence institutions. SOURCES OF DATA: Review of publications by the Brazilian Society of Pediatrics, the Brazilian Ministry of Health, the Advisory Committee on Immunization Practices (ACIP), the American Academy of Pediatrics (AAP) and the Centers for Disease Control and Prevention (CDC) covering the period from 2000 to 2005. SUMMARY OF THE FINDINGS: Local epidemiological and socioeconomic factors and the available infrastructure often define the priorities of immunobiological recommendations. The publications reviewed, both national and international, differ in terms of the vaccination schedule for tuberculosis, poliomyelitis, rotavirus, pertussis, pneumococcus, meningococcus, varicella and hepatitis A. In Brazil, there are Special Immunobiology Referral Centers (CRIE--Centros de Referência de Imunobiológicos Especiais), which, according to specific criteria, offer the population immunobiologicals that are unavailable on the public health network. CONCLUSIONS: While the use of a universal schedule is impossible due to epidemiological and operational differences, there are similarities that can be incorporated with different populations, as long as technical and scientific criteria are respected.

Elgui de Oliveira D. · Department of Pathology, Botucatu School of Medicine, State University of Sao Paulo (UNESP), Brazil. · Cancer Lett. · Pubmed #16814460 No free full text.

Abstract: The first experimental data suggesting that neoplasm development in animals might be influenced by infectious agents were published in the early 1900s. However, conclusive evidence that DNA viruses play a role in the pathogenesis of some human cancers only emerged in the 1950s, when Epstein-Barr virus (EBV) was discovered within Burkitt lymphoma cells. Besides EBV, other DNA viruses consistently associated with human cancers are the hepatitis B virus (HBV), human papillomavirus (HPV), and Kaposi sarcoma herpesvirus (KSHV). Although each virus has unique features, it is becoming clearer that all these oncogenic agents target multiple cellular pathways to support malignant transformation and tumor development.

Tatsch FF, Sette H, Vianna D. · Gerente médico de Divisāo de Virologia/TX Roche, Brazil. · Braz J Infect Dis. · Pubmed #16767316 links to  free full text

Abstract: Life expectancy has increased over the last century as it had never been before. This is the result of a combination of many favorable variables such as level of education, improved socio-economic environment and development of medicine. However, new improvements demand heavy investment. Thus, the incorporation of medical technology became a health and economic issue. The pharmacoeconomic knowledge field is being developed to help in the analysis of medical costs and patient needs. The applies to hepatitic C, a common and chronic worldwide disease. In this article, the authors describe the rational behind this type of health economic analysis and review a hepatitis C model. Overall, in a non-Brazilian scenario, it was demonstrated that peginterferon alfa-2a (40KD) is cost effective in the treatment of HCV disease.

Rapparini C. · Infectious Diseases Service, Clementino Fraga Filho University Hospital, Federal University of Rio de Janeiro, and the STD/AIDS Department, Health Secretariat of Rio de Janeiro City, Rio de Janeiro, Brazil. · Am J Infect Control. · Pubmed #16679183 No free full text.

Abstract: BACKGROUND: Exposure to bloodborne pathogens poses a serious risk to health care workers (HCWs). Surveillance systems of occupationally acquired human immunodeficiency virus (HIV) infection have been developed in several countries, mainly in the developed world. The purpose of this study was to identify cases of occupationally acquired HIV infection among HCWs in Brazil. METHODS: A systematic literature review was conducted. The databases searched were MEDLINE and LILACS (1981 to 2004), academic dissertations and theses (1987 to 2004), abstracts from national and international meetings during the last 10 years, and local and national bulletins. Reference lists to identify other relevant articles were checked. RESULTS: The database searches generated a total of 60,770 titles. Two hundred and nineteen references were finally analyzed. Four documented cases of occupational HIV infection were identified. All of the cases involved nursing staff and were percutaneous exposures. Seventy-five percent occurred after a procedure involving a needle placed directly into a vein or artery. Most (75%) had source patients with probable high viral load and low CD4 count. Two cases represented HIV seroconversion despite initiation of postexposure prophylaxis. Only one case (1/4; 25%) presented acute retroviral illness. CONCLUSION: After an extensive literature search, 4 documented occupational HIV infection cases were identified, only 1 of which had been published in a scientific journal. Our findings were consistent with the majority of documented infections worldwide. Surveillance systems are indispensable to establish and formulate rational policies for minimizing the risk of occupational infection, not only from HIV but also from hepatitis B and C viruses and other bloodborne pathogens.

Leao JC, Teo CG, Porter SR. · Departamento de Clínica e Odontologia Preventiva, Universidade Federal de Pernambuco, Recife, Brazil. · Int J Oral Maxillofac Surg. · Pubmed #16487681 No free full text.

Abstract: Hepatitis C virus (HCV) infection is a common worldwide problem, giving rise to long-term viral carriage and risk of chronic hepatic disease, hepatic malignancy and a wide spectrum of immunologically mediated disorders. The present report describes relevant data suggesting that nosocomial transmission to oral health care workers is unlikely, but in view of medical and occupational consequences of such infection, and the absence of long-term effective treatment or vaccine, the oral surgery profession must continue to be vigilant and to maintain the highest standards of infection control procedures to minimize the possible acquisition of HCV during dental treatment.

Paraná R, Almeida D. · Castro-Hepatology Unit, Unioersity Hospital of Bahia, Federal Unioersity of Bahia, Brazil. · J Clin Virol. · Pubmed #16461213 No free full text.

Abstract: In Latin America, despite the paucity of population studies, hepatitis B is considered endemic. The western Amazonia is a highly endemic area where hepatitis D is also prevalent. In this area, outbreaks of fulminant hepatitis due to H13V and HDV are frequently reported. Non-safe sexual activity seems to be the most important transmission route, but intrafamilial transmission, during early childhood, is extremely significant in Amazonia. The H13V genotype distribution is heterogeneous with a high prevalence of genotype F in the Amazonian region and genotype A in all other areas. In the region where Asian and Italian immigration occurred, genotypes B, C and D are also described.

Vigani AG, Macedo-de-Oliveira A, Pavan MH, Pedro MN, Gonçales Jr FL. · Grupo de Estudo das Hepatites Virais, Faculdade de Ciências Médicas, Universidade Estadual de Campinas, 13083-970 Campinas, SP, Brazil. · Braz J Med Biol Res. · Pubmed #16302087 links to  free full text

Abstract: Hepatitis C virus (HCV) is essentially hepatotropic but its manifestations can extend beyond the liver. It can be associated with autoimmune diseases, such as mixed cryoglobulinemia, membranoproliferative glomerulonephritis, autoimmune thyroiditis, and lymphoproliferative disorders. The mechanisms that trigger these manifestations are not completely understood. We describe a 48-year-old man with chronic HCV infection (circulating HCV RNA and moderate hepatitis as indicated by liver biopsy), cryoglobulinemia, and sensory and motor peripheral neuropathy. The diagnosis of multineuropathy was confirmed by clinical examination and electromyographic tests. A nerve biopsy revealed an inflammatory infiltrate in the perineurial space and signs of demyelination and axonal degeneration. The patient had no improvement of neurological symptoms with the use of analgesics and neuro-modulators. He was then treated with interferon-alpha (3 million units subcutaneously, 3 times per week) and ribavirin (500 mg orally, twice a day) for 48 weeks. Six months after the end of therapy, the patient had sustained viral response (negative HCV RNA) and remission of neurological symptoms, but cryoglobulins remained positive. A review of the literature on the pathogenesis and treatment of neurological manifestations associated with HCV infection is presented. This report underscores the need for a thorough evaluation of HCV-infected patients because of the possibility of extrahepatic manifestations. Antiviral treatment with interferon and ribavirin can be effective and should be considered in patients with neurological complications associated with HCV infection.

Moreira RC, Lemos MF, Longui CA, Granato C. · Laboratory of Hepatitis, Virology Service, Adolfo Lutz Institute, São Paulo, Brazil. · Braz J Infect Dis. · Pubmed #16270117 links to  free full text

Abstract: Hepatitis C is a serious public health problem throughout the world; chronic renal patients are highly exposed to this infection. This could be due to a failure to identify carriers of this disease or because of a lack of truly effective biosafety measures implemented in the dialysis units. Molecular biology techniques have allowed for the understanding of this virus in detail, including its replication mechanisms. Epidemiological studies have been made throughout the world, with the goal of determining the dissemination dynamics of this agent, in addition to examining the predominance of the different genotypes, and the possible mutants that are involved. Many questions must still be answered concerning infection by Hepatitis C virus (HCV); this is especially important for immunosuppressed patients.

Maidana MT, Sabino EC, Kallas EG. · Pró-Sangue Foundation, São Paulo, SP, Brazil. · Braz J Infect Dis. · Pubmed #16127587 links to  free full text

Abstract: An interesting interaction pattern has been found between HIV-1 and GBV-C/HGV, resulting in protection against progression to AIDS. The mechanisms involved in this interaction remain to be clarified. We examined the current knowledge concerning this coinfection and developed hypotheses to explain its effects. A better understanding of this interaction could result in new concepts, which may lead to new strategies to control HIV-1 replication and progression to AIDS.

Mendes-Corrêa MC, Barone AA. · Casa da AIDS, Division of Infectious and Parasitic Diseases, Hospital das Clinicas, Medical School, University of São Paulo, SP, Brazil. · Rev Inst Med Trop Sao Paulo. · Pubmed #15880215 links to  free full text

Abstract: Hepatitis C virus (HCV) and human immunodeficiency virus (HIV) share the same transmission mechanisms. The prevalence of HCV in the HIV-infected population varies from region to region, throughout the world, depending on different exposure factors to both viruses. Co-infection with HIV accelerates the progression of the disease caused by HCV, appears to worsen the progression of the HIV infection and increases HCV transmission. Therefore, clinical management and treatment of HCV is a priority in medical facilities that receive HIV-infected patients. Clinical management of these patients involves specific diagnostic procedures and appropriately trained medical staff. The indication of treatment should meet specific clinical and laboratory criteria. There are a number of drugs currently available to treat hepatitis C in co-infected patients.

Carrilho FJ, Mendes Clemente C, Silva LC. · Department of Gastroenterology, University of São Paulo School of Medicine, São Paulo, Brazil. · Gastroenterol Hepatol. · Pubmed #15771857 No free full text.

Abstract: This review has the objective to discuss the epidemiological aspects of the enterically transmitted hepatitis A and E in Brazil. The prevalence of hepatitis A varies greatly in different Brazilian regions, from 56% in South and Southeast to 93% in North region (Manaus, Amazon). Such differences are also found in different socioeconomic levels among age groups. A significantly higher prevalence was seen in the low socioeconomic group between 1-30 years. This difference is most striking in the first 10 years of age (23.5% vs 60.0%, high/middle vs low, respectively). Despite the improvements in sanitary conditions, hepatitis A is still endemic and outbreaks may occur. As an increasing proportion of the population is becoming susceptible to hepatitis A virus infection and as adult individuals may present more severe forms of the disease, the authors conclude that the implement of hepatitis A vaccination should be considered. Some Brazilian data have shown that the genotype found in our country were IA and IB. Isolates from this study were closely related genetically (or even identical) to isolates originating in other South American countries and overseas, providing firm evidence for epidemiological links between persons who travel to endemic areas. In spite of favorable environmental conditions, outbreaks of hepatitis E have never been reported in Brazil. Nevertheless, reports have demonstrated the evidence of anti-hepatitis E virus antibodies in some Brazilian regions. The seroprevalence of IgG anti-hepatitis E virus among normal populations shows positivities of 6.1% in gold-miners, 3.3% in general population, 2.0-7.5% in blood donors, 1.0% in pregnant women, and 4.5% in children, with no differences among regions. In populations at risk the prevalence of anti-hepatits E virus varies greatly. Among patients with acute non-A, non-B, non-C hepatitis 2.1% was detected in the Southeast to 29% in the Northeast, in 10.6% of acute non-A, non-B, non-C hepatitis relatives in the Amazon basin, in 12% of acute sporadic non-A non-B hepatitis patients in the Northeast, a co-infection with acute hepatitis A in 25 to 38% in the Northeast, in 14 to 18% among prostitutes and women considered at risk for human immunodeficiency virus in the Southeast, and in 12% of the intravenous drug users in the Southeast.

da Fonseca JC. · Universidade Federal do Amazonas da Fundação de Medicina Tropical, Manaus, AM. · Rev Soc Bras Med Trop. · Pubmed #15586904 No free full text.

Abstract: The author makes a revision and an update on the results of the researches involving the Labrea hepatitis and others fulminant hepatitis in western Brazilian Amazon, with emphasis in the clinical, epidemiologic, histopatologic characteristics and viral etiology as hepatitis B and D viruses. Potential etiologic role of same anothers hepatotropic virus is considered.

Souto FJ. · Núcleo de Estudos de Doenças Infecciosas e Tropicais da Faculdade de Ciências Médicas da Universidade Federal de Mato Grosso, Cuiabá, MT. · Rev Soc Bras Med Trop. · Pubmed #15586899 No free full text.

Abstract: Hepatitis B is the main cause of hepatic disease in the Amazon and a biggest problem for its public health. Outbreaks and high prevalence of hepatitis B markers have been reported among immigrants recently arrived in northmost part of the Brazilian State of Mato Grosso. The hepatitis B surface antigen subtypes analysis suggests that the immigrants brought the virus themselves. Likely environmental and behavioral factors have facilitated the hepatitis B spread among these immigrant communities. Recent data show that surveillance and vaccination of immigrants have decreased the incidence of hepatitis B in this region. The increasing number of hepatitis delta cases among hepatitis B carriers from the Northmost part of Mato Grosso State has been detected as a consequence of a increasing contact with neighbor States that present high prevalence of this coinfection.

da Fonseca JC, Brasil LM. · Gerência de Virologia da Fundação de Medicina Tropical, Manaus, AM. · Rev Soc Bras Med Trop. · Pubmed #15586890 No free full text.

Abstract: The article evaluates available scientific information concerning the prevalence and clinical characteristics of hepatitis C virus infection in the Brazilian Amazon, a know endemic area for hepatitis A, B and D viruses infection. All the information was obtained through extensive analysis of original and review articles and abstracts published in distinguished journals or in scientific meetings. In the Amazon Region, HCV infection prevalence rate in the general population varies from 1.1 to 2.4%. Among blood donators the prevalence rate varies from 0.8 to 5.9%. Pard (Eastern Amazon) and Acre (Western Amazon) State present the highest rates, 2% and 5.9%, respectively. In respect to the HCV infection prevalence rate in the risk groups, one observates high prevalence. In the Brazilian Amazon, infection by HCV seems to cope in the same way of infection in other parts of the world among the hemodialized (48.1 - 51.9%), health professionals (3.2%), HCV carriers contactants (10%) and lichen plannus patients (7.5%). There is a significant predominance of genotype 1, being sub-type 1b the most frequent. The HCV infection is similar in men and women and most of the infected are above 39 years of age. The major route of infection is parenteral and the major risk factors are blood transfusion and surgical procedures. HCV is rarely responsable for acute severe hepatitis in this region. On the other hand, of all chronic hepatitis, 22.6% are attributed to HCV in the Western Amazon and 25% in the Eastern Amazon. In the Brazilian Amazon, infection by HCV seems to cope in the same way of infection in other parts of the world.

Andrade ZA. · Laboratório de Patologia Experimental, Centro de Pesquisas Gonçalo Moniz-Fiocruz, Rua Valdemar Falcão 121, 40295-001 Salvador, BA, Brazil. · Mem Inst Oswaldo Cruz. · Pubmed #15486635 links to  free full text

Abstract: Gross anatomical features and a complex set of vascular changes characterize schistosomal hepatopathy as a peculiar form of chronic liver disease, clinically known as "hepatosplenic schistosomiasis". It differs from hepatic cirrhosis, although clinical and pathological aspects may sometimes induce confusion between these two conditions. Intrahepatic portal vein obstruction and compensatory arterial hypertrophy render the hepatic parenchyma vulnerable to ischemic insult. This may lead to focal necrosis, which may give place to focal post-necrotic scars. These events are of paramount importance for the clinico-pathological evolution of schistosomal hepatopathy. Although portal fibrosis due to schistosomiasis sometimes reveals numerous myofibroblasts, it does not mean that such fibrosis belongs to a peculiar type. Damage to the muscular walls of the portal vein may be followed by dissociation of smooth muscle cells and their transition toward myofibroblasts, which appear only as transient cells in schistosomal portal fibrosis. Studies made with plastic vascular casts, especially those with the murine model of "pipestem" fibrosis have helped to reveal the mechanisms involved in systematized portal fibrosis formation. However, the factors involved in the pathogenesis of hepatosplenic disease remain poorly understood. A process of chronic hepatitis is a common accompaniment of portal fibrosis in schistosomiasis. Most of the times it is caused by concomitant viral infection. However, no special interaction seems to exist between schistosomal hepatopathy and viral hepatitis.

El Khouri M, dos Santos VA. · Immunology Section, Central Lab Division, Hospital das Clínicas, Faculty of Medicine, University of São Paulo, São Paulo, SP, Brazil. · Rev Hosp Clin Fac Med Sao Paulo. · Pubmed #15361988 links to  free full text

Abstract: The global prevalence of hepatitis B virus is estimated to be 350 million chronic carriers, varying widely from low (<2%, as in Western Europe, North America, New Zealand, Australia, and Japan) to high (>8% as in Africa, Southeast Asia, and China). The overall prevalence in Brazil is about 8%. There are currently 7 genotypic variations, from A to G, and also 4 main surface antigen subtypes: adw, ayw, adr, and ayr. There has been great interest in identifying the geographic distribution and prognosis associated with the various genotypes and subtypes. Although the serologic test is highly sensitive and specific, it does not detect cases of mutant hepatitis B, which is increasingly common worldwide due to resistance and vaccine escape, antiviral therapy, and immunosuppression, among other causes. Alterations in surface, polymerase, X region, core, and precore genes have been described. The main mutations occur in surface and in core/precore genes, also known as occult hepatitis, since its serologic markers of active infection (HBsAg) and viral replication (HBeAg) can be negative. Thus, mutation should be suspected when serologic tests to hepatitis B show control of immunity or replication coincident with worsened clinical status and exclusion of other causes of hepatitis.

de Andrade DR, de Andrade DR. · Laboratory of Medical Investigation/LIM-54, University of São Paulo, School of Medicine, Sao Paulo, SP, Brazil. · Rev Inst Med Trop Sao Paulo. · Pubmed #15286811 links to  free full text

Abstract: The mechanisms that determine viral clearance or viral persistence in chronic viral hepatitis have yet to be identified. Recent advances in molecular genetics have permitted the detection of variations in immune response, often associated with polymorphism in the human genome. Differences in host susceptibility to infectious disease and disease severity cannot be attributed solely to the virulence of microbial agents. Several recent advances concerning the influence of human genes in chronic viral hepatitis B and C are discussed in this article: a) the associations between human leukocyte antigen polymorphism and viral hepatic disease susceptibility or resistance; b) protective alleles influencing hepatitis B virus (HBV) and hepatitis C virus (HCV) evolution; c) prejudicial alleles influencing HBV and HCV; d) candidate genes associated with HBV and HCV evolution; d) other genetic factors that may contribute to chronic hepatitis C evolution (genes influencing hepatic stellate cells, TGF-beta 1 and TNF-alpha production, hepatic iron deposits and angiotensin II production, among others). Recent discoveries regarding genetic associations with chronic viral hepatitis may provide clues to understanding the development of end-stage complications such as cirrhosis or hepatocellular carcinoma. In the near future, analysis of the human genome will allow the elucidation of both the natural course of viral hepatitis and its response to therapy.