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1.
The list of hepatitis viruses is increasing over the years. Now the viruses range from A to G. Hepatitis A virus is a short incubation RNA virus which is transmitted oro-faecally. It does not cause chronic illness but may be fatal in a few cases especially in pregnancy. It can now be prevented by vaccination. Hepatitis B virus is a long incubation DNA virus which is transmitted mainly through blood and blood products. It causes chronic illness and can lead to liver cancer in some cases. It can be prevented by vaccination and WHO is now recommending global vaccination of all infants irrespective of endemicity of hepatitis B virus. Hepatitis C virus is an RNA virus which used to be known as parenterally transmitted non A non-B virus. It leads to chronic illness and can lead to liver cancer. It is now responsible for most cases of post transfusion hepatitis in Europe, North America and Asia. Hepatitis Delta virus is a defective virus which requires hepatitis B virus for its existence. Thus it affects only those who have hepatitis B virus. Hepatitis E virus used to be known as the enterically transmitted non-A non-B virus. It is transmitted oro-faecally and seems not to lead to chronic illness. It is endemic in some areas like Middle East and parts of Africa. Hepatitis G virus is just being described. More information about it will soon be available.  相似文献   

2.
The therapy of viral hepatitis has great medical and socioeconomic impact. Today chronic viral hepatitis is the most important cause for chronic liver disease, liver cirrhosis, and hepatocellular carcinoma. Hepatitis A and E cause acute courses exclusively whereas infection with the hepatitis B, C, and D virus might result in chronic hepatitis as well. The goal of therapy of chronic viral hepatitis has to be a reduction/normalisation of elevated transaminases, decrease of the serologic parameters of active viral replication, improvement of histology and prevention of complications of chronic hepatitis. The only drug with proven benefit in the treatment of chronic viral hepatitis is interferon alpha. This therapy results in a sustained response in 25 to 40% for hepatitis B and 10 to 25% for hepatitis C infection. New developments under clinical evaluation are Lamivudine and Famciclovir in the treatment of HBV-infection and Ribavirin in combination with INFa for chronic HCV-infection.  相似文献   

3.
The development of molecular biology techniques has enabled us to clone the genetic sequence of three new hepatitis viruses, namely, hepatitis C virus, hepatitis E virus and hepatitis G, or GBV-C virus in the last decade. Hepatitis C virus (HCV) is now known to account for the majority of the parenterally transmitted non-A, non-B hepatitis and hepatitis E virus (HEV) is the major cause of the epidemics of enterally transmitted non-A, non-B hepatitis in the less developed countries, mainly through contaminated water supplies. While 80% of those who were infected with HCV will become chronic carriers, there is no known chronic carrier state for HEV. To date, 6 major genotypes of HCV were identified, with various variants of genotype 6 described in Southeast Asia. In Singapore, the majority of our chronic hepatitis C patients are infected with genotype 1. The seroprevalence rate of HEV is 10% to 14% in Singapore. This probably reflects our suboptimal sanitary condition in the past rather than a reflection of a currently high HEV infection rate in our population. However, local cases of acute hepatitis E have been reported. As for the most recently cloned hepatitis G virus, its aetiologic role in the remaining cases of non-A, non-B hepatitis is still unclear. Some preliminary evidence suggests that it may be just an innocent bystander with limited pathogenicity and it certainly cannot account for all the remaining cases of non A-E hepatitis. Hence, the search for yet another hepatitis virus continues.  相似文献   

4.
BACKGROUND/AIMS: Chronic graft hepatitis occurs in 20-30% adults after liver transplantation but the prevalence and causes in children are not known. In adults, hepatitis C virus infection is prevalent prior to transplantation and recurrent infection is a frequent cause of graft dysfunction. The significance of the recently described hepatitis G virus infection remains unproven. The aim of this study was to examine the role of hepatitis C virus and hepatitis G virus infection in chronic graft hepatitis after paediatric liver transplantation. METHODS: The prevalence of graft hepatitis and the role of hepatitis C virus and hepatitis G virus infections in 80 children after liver transplantation have been studied, with a median follow up of 4.4 years (range 0.4 to 10.7), and the persistence of hepatitis G infection in the presence of immunosuppression has been determined. RESULTS: Chronic graft hepatitis was diagnosed in 19/80 (24%) children and was most frequently seen in children transplanted for cryptogenic cirrhosis (71%). There was no significant difference in the prevalence of chronic hepatitis in those transplanted before or after donor anti-HCV screening. Hepatitis C infection occurred in three children transplanted prior to donor screening but in only one was associated with chronic hepatitis. Hepatitis G infection was found in 22/79 (28%) transplant recipients but was not associated with graft hepatitis. In 17/21 children hepatitis G infection persisted for a median of 5.2 years after transplantation. CONCLUSION: Chronic hepatitis occurred in 24% of children after liver transplantation, a similar prevalence to that in adults. Cryptogenic liver disease predisposed to graft hepatitis, but neither hepatitis C nor hepatitis G infection was associated. Hepatitis G virus caused a frequent and usually persistent infection after transplantation.  相似文献   

5.
Hepatitis C, which is caused by the hepatitis C virus (HCV), is a major public health problem in the United States. HCV is most efficiently transmitted through large or repeated percutaneous exposures to blood. Most patients with acute HCV infection develop persistent infection, and 70 percent of patients develop chronic hepatitis. HCV-associated chronic liver disease results in 8,000 to 10,000 deaths per year, and the annual costs of acute and chronic hepatitis C exceed $600 million. An estimated 3.9 million Americans are currently infected with HCV, but most of these persons are asymptomatic and do not know they are infected. To identify them, primary health care professionals should obtain a history of high-risk practices associated with the transmission of HCV and other bloodborne pathogens from all patients. Routine testing is currently recommended only in patients who are most likely to be infected with HCV.  相似文献   

6.
7.
Hepatitis G virus (HGV) is a newly described RNA virus that is parenterally transmitted and has been found frequently in patients with chronic hepatitis C infection. To determine the impact of hepatitis G virus co-infection on morbidity and mortality following liver transplantation, we measured HGV RNA by polymerase chain reaction in pre and posttransplantation sera from a cohort of patients transplanted for chronic hepatitis C and a control group of patients transplanted for nonviral causes who were negative for hepatitis C virus (HCV) RNA in serum. The overall prevalence rate of HGV RNA in transplanted patients with chronic hepatitis C was 20.7%. HGV infection was present before transplantation in 13% while it appeared to have been acquired at the time of transplantation in 7.4%. Mean serum alanine aminotransferase activity, hepatic histological activity, and patient and graft survival were similar between HGV-positive and HGV-negative patients. The prevalence rate of HGV RNA in transplanted controls was 64% (P < .01) with a significantly higher rate of acquisition of HGV infection following transplantation (53%, P < .001) when compared with patients with chronic hepatitis C. Mean serum alanine aminotransferase activity was significantly lower in the control patients with HGV infection alone following transplantation than in patients co-infected with hepatitis C (37 +/- 9 vs. 70 +/- 33 U/L, P < .01). Thus, HGV is frequently found in transplantation patients co-infected with hepatitis C although it appears to have minimal clinical impact. In patients transplanted for nonviral causes of end-stage liver disease, a high rate of hepatitis G acquisition at the time of transplantation may occur but does not appear to predispose to chronic hepatitis.  相似文献   

8.
Acute viral hepatitis is the most usual cause of jaundice and acute liver failure, whereas chronic viral hepatitis is the major cause of liver cirrhosis and hepatocellular carcinoma. Taking into the consideration the morbidity and mortality of such lesions, their prophylaxis is a mandatory procedure. In this review we discuss the general measures and the active and passive immunoprophylaxis against hepatitis A. B and Yellow fever, and the general management of hepatitis C. D. and E virus infection.  相似文献   

9.
10.
Testing is now available for five recognised hepatitis viruses (A, B, C, D and E), and molecular technology is uncovering further hepatotropic viruses. An enteric agent isolated from human stool samples and transmitted experimentally to primates is a candidate hepatitis F virus. A provisionally designated blood-borne hepatitis G virus is associated with acute and chronic non-ABCDE hepatitis and has a worldwide distribution. A group of flavi-like viruses, the GB group, also blood borne, has also been reported. The role of two of these viruses, GBV-A and GBV-B, in human viral hepatitis has not been determined, but a third agent, GBV-C, is associated with acute and chronic hepatitis and appears to be a West African variant of hepatitis G. Our current knowledge suggests that the hepatitis alphabet may need to be extended even after inclusion of some of these new viruses.  相似文献   

11.
Hepatitis virus infections belong to the major etiological factors of both acute and chronic liver diseases. During the last years--apart from the passive immunoprophylaxis through the administration of immunoglobulin--safe and efficacious hepatitis vaccines (against hepatitis A and B viruses) has also became available in Hungary. In this review the authors focus on the practical considerations of the immunoprophylaxis of hepatitis viruses. General consensus concerning the clinical use of hepatitis A vaccine has not been accepted, and human immunoglobulin is the only acceptable measure to prevent postexposure hepatitis A virus infection. Hepatitis B immunoglobulin (HBIG) is administered to prevent hepatitis B infection after exposure of HBV-contaminated body fluids and in infants born to HbsAg-positive mothers. Recombinant hepatitis B vaccine has the crucial note in the WHO's program for eradication of hepatitis B. While in the areas of high endemicity the implementation of universal hepatitis B vaccination is recommended, in the countries with low HbsAg-carrier prevalence infants' and/or adolescents' vaccination can offer alternative choices. Prevention of health-care workers against hepatitis virus infection and the vaccination of patients with chronic liver disease are also of great importance. There is also an urgent need to establish multidisciplinary professional cooperation to be able to carry out effectively the WHO's recommendations for prevention of hepatitis B infection.  相似文献   

12.
BACKGROUND: Little is known about the relation of the newly discovered hepatitis G virus (HGV) to the cause and clinical course of acute and chronic viral hepatitis. METHODS: We selected patients from a surveillance study of acute viral hepatitis in four U.S. counties who had acute disease during 1985 to 1986 or 1991 to 1995. Serum samples were tested for HGV RNA by the polymerase chain reaction. RESULTS: HGV RNA was detected in 4 of 45 patients with a diagnosis of non-A-E hepatitis (9 percent), 23 of 116 patients with hepatitis C (20 percent), 25 of 100 patients with hepatitis A (25 percent), and 32 of 100 patients with hepatitis B (32 percent) (P<0.05 for the comparison of hepatitis B with hepatitis non-A-E or C). The clinical characteristics of the acute illness were similar for patients with HGV alone and those with hepatitis A, B, or C with or without HGV infection. During a follow-up period of one to nine years, chronic hepatitis did not develop in any of the patients with HGV alone, but 75 percent were persistently positive for HGV RNA, as were 87 percent of those with both hepatitis C and HGV infection. The rates of chronic hepatitis were similar in patients with hepatitis C alone (60 percent) and those with both hepatitis C and HGV infection (61 percent). CONCLUSIONS: The evidence from this surveillance study does not implicate HGV as an etiologic agent of non-A-E hepatitis. Persistent infection with HGV was common, but it did not lead to chronic disease and did not affect the clinical course in patients with hepatitis A, B, or C.  相似文献   

13.
Hepatitis A virus infection is major cause of acute hepatitis in the United States, accounting for approximately 75,000 cases of clinical illness each year. These infections occur among persons in every age group and are associated with a variety of exposures related to fecal-oral transmission. Recently, the U.S. Food and Drug Administration approved licensure of two inactivated hepatitis A vaccines. Both vaccines are highly immunogenic and have been licensed in pediatric and adult formulations. The prevention of hepatitis A virus infection is directly related to many aspects of family practice, and family physicians may see patients in a variety of settings that warrant administration of hepatitis A vaccine. Groups for whom vaccination is currently recommended include international travelers, children in communities with high rates of hepatitis A virus infection, men who have sex with men, Illicit drug users, patients with chronic liver disease and persons with clotting factor disorders.  相似文献   

14.
IM Alexander 《Canadian Metallurgical Quarterly》1998,23(10):13-4, 17-20, 25-6 passim; quiz 44-5
Many patients in primary care settings have hepatitis. This article discusses signs and symptoms of acute hepatitis and outlines differential diagnoses. The characteristics and methods of transmission of individual hepatotropic viruses, including hepatitis A, B, C, D, E, and G/GB-C are reviewed. Serologic diagnosis of the causative agent is explained. Patient care includes sign and symptom management, medication administration, prevention of transmission to friends and family members, follow-up serologic testing, and evaluation for chronic infection. Preventive measures include vaccination and the use of immune globulin agents for hepatitis A and B. Health care providers should be aware of recent developments in the treatment of chronic infection with hepatitis B and C.  相似文献   

15.
The practice of dermatology has always carried with it the risk of patient-acquired infection. This review covers health risks associated with the care of HIV-infected patients and patients who are chronic carriers of hepatitis B or C virus, protection options to reduce exposure, and protocols should exposure occur. Hepatitis B continues to be a major risk to health care workers, killing approximately 200 per year. In contrast, as of 1990, only 327 total health care personnel had acquired HIV, with no deaths reported. Data are lacking regarding hepatitis C, but it appears to be an increasing concern. Needlesticks are the most common form of occupational transmission, with an infectivity rate of 30% for hepatitis B, 3% for hepatitis C, and 0.3% for HIV. Universal precautions are the cornerstones of safety. Hepatitis B vaccination, zidovudine prophylaxis, and hepatitis C therapy are discussed as postexposure recommendations are reviewed.  相似文献   

16.
17.
Viral hepatitis belongs to the most important infectious diseases worldwide. More than 300 million chronic HBsAg carriers and chronic HCV carriers exist, respectively. High endemic areas of viral hepatitis are Asia, Africa, Latin America and the Near, Middle and Far East. Viral hepatitis is also very important in health care workers. Today viral hepatitis can be differentiated from type A to type E (G) based on immunological and molecular assays. While enterally transmitted hepatitis type A and type E only induce acute and rare fulminant disease, hepatitis type B, C and D often induce chronic progressive disease including liver cirrhosis with typical complications due to the portal hypertension and with a high rate of association with the development of primary liver cancer (HCC). This review focusses on viral hepatitis-related surgical problems, including liver transplantation.  相似文献   

18.
The hepatitis B virus (HBV) is the most prevalent chronic infectious disease in the world, and should be better understood by nurses caring for families. Perinatal acquisition is the major cause of infection in infants and children. Without vaccine during infancy, 90% of infants born to women positive for the virus will go on to become lifelong carriers. There are significant sequelae associated with HBV infection, ranging from fulminant HBV to chronic liver disease to an increased risk for carcinoma. A comprehensive prevention and treatment strategy has been developed by the Centers for Disease Control and Prevention, which includes screening of all pregnant women for the presence of HBV, the administration of hepatitis B immunoglobulin (HBIG) at birth, and the administration of hepatitis B vaccine at birth, at 1 month of age, and at 6 months of age. Nurses working in the perinatal and pediatric specialties must understand the implications of HBV to help prevent transmission and to assist in the coordination of care and advocacy for affected populations. The community health implications for the care of women and children with HBV are clear, giving nurses the opportunity to develop a closer linkage between hospital- and community-based nursing practice.  相似文献   

19.
Little is known about vertical transmission of hepatitis E virus from infected mothers to their infants. We studied eight babies born to mothers infected with hepatitis E in third trimester. One baby was icteric at birth with elevated transaminases and four babies had anicteric hepatitis. Two babies were born with hypothermia and hypoglycaemia and died within 24 h; one had massive hepatic necrosis. Hepatitis E virus RNA was detected by PCR in cord or birth blood samples of five infants. Six infants had evidence of hepatitis E infection. We conclude that hepatitis E virus is commonly transmitted from infected mothers to their babies with significant perinatal morbidity and mortality.  相似文献   

20.
Hepatitis B remains a significant risk to patients receiving chronic hemodialysis. Hepatitis B vaccines are effective in providing protection against this infection. However, the minimum antibody level necessary to guarantee an efficacious protection is not clear. Little is known about the effect of this vaccine in persons treated with erythropoietin (EPO) and in patients with hepatitis C virus (HCV) infection. We have studied 36 chronic hemodialysis patients; 17 of them receiving EPO and 9 were diagnosed as having HCV infection. Effective immunity (antibody titer higher than 100 mIU/ml) was observed in 61.1% of the participants and was not influenced by EPO administration, but the effective immunization rate was lower in HCV infected patients (33.3% vs. 70.3%, p < 0.05). These results suggest the possibility that HCV infection may modify the effectiveness of hepatitis B vaccine.  相似文献   

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