Current issues in the management of paediatric viral hepatitis

Role of microRNA 4717, its effects on programmed cell death protein-1 in hepatitis B infection, and interaction between PDCD1 and miR-4717

It is suggested that programmed cell death protein-1 (PD-1) is involved in hepatitis B virus (HBV) infection, the leading cause of hepatocellular carcinoma globally. This study was multi-aimed, that is, to investigate the role of microRNA (miR) 4717 and its target, PD-1 and to determine how the rs10204525 polymorphism in the 3′ untranslated region (3′UTR) of PD-1 affects its interaction with miR-4717. The expression levels of miR-4717 with various single-nucleotide polymorphisms were measured by reverse transcription–quantitative polymerase chain reaction (RT-qPCR). A total of 54 tissue samples from HBV-infected individuals were collected, genotyped, and categorized into three groups; AA (n = 32), AG (n = 18), and GG (n = 4). The expression levels of gene PDCD1 and its corresponding PD-1 protein were significantly declined in the AA group as compared to AG and GG groups. There was a negative linear association between PDCD1 and miR-4717 in the tissue samples. HEPG2 cells transfected with an miR-4717 mimic or PD-1 small interfering (si)RNA exhibited significantly reduced expression levels of PDCD1 and PD-1, whereas cells transfected with an inhibitor of miR-4717 demonstrated greater expression levels of PDCD1 and PD-1 compared with the scramble control. In addition, cell viability and apoptosis were assessed in cells transfected with an miR-4717 mimic, PD-1 siRNA, or an miR-4717 inhibitor. Results revealed that treatment with the miR-4717 mimic or PD-1 siRNA enhanced viability of cells and reduced apoptosis. The results of this study suggest that rs10204525 polymorphism interferes with the interaction between PD-1 and miR-4717 and therefore induces apoptosis in liver cancer cells.

Age-period-cohort analysis of hepatitis A incidence rates in Korea from 2002 to 2012

OBJECTIVES

This study aimed to evaluate the epidemiology of hepatitis A in Korea from 2002 to 2012 using age-period-cohort analyses.

METHODS

We used claims data from the Korean National Health Insurance Corporation for the entire population. Census data from 2010 were used as the standard population. The incidence of hepatitis A was assumed to have a Poisson distribution, and the models and effects were evaluated using the intrinsic estimator method, the likelihood ratio, and the Akaike information criterion.

RESULTS

The incidence of hepatitis A gradually increased until 2007 (from 17.55 to 35.72 per 100,000 population) and peaked in 2009 (177.47 per 100,000 population). The highest incidence was observed among 27-29-year-old individuals when we omitted data from 2005 to 2007. From 2005 to 2007, the peak incidence was observed among 24-26-year-old individuals, followed by 27-29-year-olds. The best model fits were observed when the age-period-cohort variables were all considered at the same time for males, females, and the whole population.

CONCLUSIONS

The incidence of hepatitis A exhibited significant age-period-cohort effects; its incidence peaked in 2009 and was especially high among Koreans 20-39 years of age. These epidemiological patterns may help predict when high incidence rates of hepatitis A may occur in developing countries during their socioeconomic development.

Hepatitis C Viral Infection in Children: Updated Review

Hepatitis C virus (HCV) infection is a major medical challenge affecting around 200 million people worldwide. The main site of HCV replication is the hepatocytes of the liver. HCV is a positive enveloped RNA virus from the flaviviridae family. Six major HCV genotypes are implicated in the human infection. In developed countries the children are infected mainly through vertical transmission during deliveries, while in developing countries it is still due to horizontal transmission from adults. Minimal nonspecific and brief symptoms are initially found in approximately 15% of children. Acute and chronic HCV infection is diagnosed through the recognition of HCV RNA. The main objective for treatment of chronic HCV is to convert detected HCV viremia to below the detection limit. Children with chronic HCV infection are usually asymptomatic and rarely develop severe liver damage. Therefore, the benefits from current therapies, pegylated-Interferon plus ribavirin, must be weighed against their adverse effects. This combined treatment offers a 50-90% chance of clearing HCV infection according to several studies and on different HCV genotype. Recent direct acting antiviral (DAA) drugs which are well established for adults have not yet been approved for children and young adults below 18 years. The most important field for the prevention of HCV infection in children would be the prevention of perinatal and parenteral transmission. There are areas of focus for new lines of research in pediatric HCV-related disease that can be addressed in the near future.

Single Clinical Practice's Report of Testing Initiation, Antibody Clearance, and Transmission of Hepatitis C Virus (HCV) in Infants of Chronically HCV-Infected Mothers

Low likelihood for detection of HCV infection, transient viremia, and maternal HCV antibody before 10 months of age limits the value of early initiation of HCV testing in infants born to HCV infected mothers.

Background. Perinatally acquired hepatitis C virus (HCV) is the main source of pediatric HCV infection. However, the best time for initiation of screening and follow up of these infants is still unknown. Analysis of the clinical data of infants born to HCV-infected mothers, transmission rates, and pathway of HCV testing could be important for optimization of their management.

Methods. Children of mothers with chronic HCV infection, who were observed between 1998 and 2013 at the pediatric infectious disease clinic for the first 18 months of their life, were eligible for enrollment. We analyzed the factors influencing initiation of HCV testing in these children and rate of HCV transmission as demonstrated by consecutive HCV antibody and HCV ribonucleic acid (RNA) amplification testing.

Results. One hundred and forty-two mother-infant pairs were enrolled. The majority of mothers were intravenous drug users, had carried to term, and delivered vaginally. A high proportion of infants had at least 1 positive anti-HCV antibody assay without viremia. True HCV infection and intermittent viremia were recorded in 3.5% and 1.4% of infants, respectively. Initiation of HCV testing after 10 months of age was associated with a significant decline in the probability of obtaining a positive HCV antibody of maternal origin.

Conclusions. The low likelihood for detection and confirmation of true HCV transmission before 10 months of age could challenge the early initiation of HCV screening of infants exposed to maternal HCV infection but may affect the parental need for early monitoring and counseling.

Hepatitis A Virus Infection, Vaccination and Iranian Healthcare Workers

CONTEXT

Hepatitis A virus (HAV) infection is an important public health problem. It is estimated that about 1.4 million cases of HAV infection occur every year worldwide. Non-immune healthcare workers (HCWs) can be at higher risk of HAV infection in comparison to general population and an appropriate preventive method should be considered for them.

EVIDENCE ACQUISITION

For finding related articles, a comprehensive search was performed in Scopus, PubMed and Google Scholar and all appropriate combinations of following keywords were considered; "healthcare provider", "healthcare personnel", "healthcare worker", "nurse" "medical students", "Iran", "Hepatitis A" and "vaccination". Also we did a search in Persian language in Google scholar and scientific information database (SID) to find related Persian literature.

RESULTS

A gradual shift in age of HAV infection has been seen from childhood toward adulthood. Data about HAV seropositivity among Iranian HCWs are very limited. However based on the recent studies, it seems that HAV seropositivity has been reduced among HCWs in comparison with the past. All recent studies have suggested HAV vaccination for HCWs.

CONCLUSIONS

Available limited studies show that Iranian healthcare personnel need HAV vaccination. However, for selecting an appropriate preventive method for this high risk group, more original studies are still needed.

Hepatitis C Virus Sensing by Human Trophoblasts Induces Innate Immune Responses and Recruitment of Maternal NK Cells: Potential Implications for Limiting Vertical Transmission

Hepatitis C virus (HCV) is the world's most common blood-borne viral infection for which there is no vaccine. The rates of vertical transmission range between 3 and 6% with odds 90% higher in the presence of HIV coinfection. Prevention of vertical transmission is not possible because of lack of an approved therapy for use in pregnancy or an effective vaccine. Recently, HCV has been identified as an independent risk factor for preterm delivery, perinatal mortality, and other complications. In this study, we characterized the immune responses that contribute to the control of viral infection at the maternal-fetal interface (MFI) in the early gestational stages. In this study, we show that primary human trophoblast cells and an extravillous trophoblast cell line (HTR8), from first and second trimester of pregnancy, express receptors relevant for HCV binding/entry and are permissive for HCV uptake. We found that HCV-RNA sensing by human trophoblast cells induces robust upregulation of type I/III IFNs and secretion of multiple chemokines that elicit recruitment and activation of decidual NK cells. Furthermore, we observed that HCV-RNA transfection induces a proapoptotic response within HTR8 that could affect the morphology of the placenta. To our knowledge, for the first time, we demonstrate that HCV-RNA sensing by human trophoblast cells elicits a strong antiviral response that alters the recruitment and activation of innate immune cells at the MFI. This work provides a paradigm shift in our understanding of HCV-specific immunity at the MFI as well as novel insights into mechanisms that limit vertical transmission but may paradoxically lead to virus-related pregnancy complications.

T-helper 17-related cytokines and IgE antibodies during hepatitis A virus infection in children

We determined the serum IgE levels and T-helper (Th)17-related cytokines during distinct hepatitis A virus (HAV)-induced clinical courses in children. A significantly higher concentration of macrophage inflammatory protein 3α, interleukin (IL)-17E and IL-17F in HAV-infected children with intermediate liver injury compared with those with minor liver damage was found. A reduction in the IgE levels in those patients who showed the highest levels of IL-17F in the group of intermediate liver injury was found. The data suggested that the Th17-related profile is associated with the severity of HAV infection and might play a role on the modulation achieved by HAV during allergies.

Hepatitis B virus infection in children

For two decades, hepatitis B vaccine has been integrated into national routine childhood vaccination programs in almost all countries. The prevalence of HBsAg has decreased in children worldwide. However, there are children who miss the benefit of hepatitis B vaccine in some regions and countries. Long-term follow-up studies have revealed the clinical outcomes of chronic hepatitis B virus infection in children. A small percentage of chronically infected children develop liver cirrhosis and hepatocellular carcinoma. However, it is controversial who should be treated and when antiviral treatment should be initiated in children. Compared with adult studies, the data are insufficient to evaluate the pathogenesis of hepatitis B infection and the efficacy of antiviral treatment in childhood. New antiviral drugs have been approved for children and adults. Also, oral antiviral drugs are administered to pregnant women to reduce the hepatitis B virus mother-to-child transmission rate.

Chronic hepatitis B virus infection in children and adolescents in Japan

BACKGROUND

Hepatitis B e antigen (HBeAg) seroconversion is an important event in patients with chronic hepatitis B virus (HBV) infection. This study aimed to clarify the outcome of long-term follow-up of chronic HBV infection and the factors affecting HBeAg seroconversion in children in Japan.

METHODS

Patients who were first examined at our institution between 1980 and 2012, who were <20 years of age at the time of this initial visit, and who were positive for hepatitis B surface antigen for at least 6 months were identified retrospectively. Sex, age at diagnosis, HBV genotype, maximum serum alanine aminotransferase (ALT) level, occurrence of hepatitis flare-ups (yes/no), and transmission route were evaluated to identify the predictors of HBeAg seroconversion.

RESULTS

A total of 205 children with chronic HBV were enrolled. Among them, 192 were positive for HBeAg upon diagnosis of chronic HBV infection. Out of this group, 95 (49%) achieved HBeAg seroconversion and 43 (21%) received treatment during the follow-up period. Only the maximum serum ALT level was significantly associated with the achievement of HBeAg seroconversion by multivariate analysis (P < 0.05). Kaplan-Meier analysis showed that the median times to HBeAg seroconversion (50% achievement of HBeAg seroconversion) of the treated and untreated children were 10.2 and 12.0 years, respectively. The cumulative proportion of HBeAg seroconversion was significantly higher in the treated children than in the untreated children (P = 0.02).

CONCLUSIONS

A higher serum ALT level was a predictor for HBeAg seroconversion. Antiviral treatment could accelerate the achievement of HBeAg seroconversion in HBV-infected children.

High prevalence of occult hepatitis B virus genotype H infection among children with clinical hepatitis in west Mexico

Studies on the prevalence of infection with hepatitis B virus (HBV) among children are scarce in Latin American countries, especially in Mexico. This study was aimed to investigate the prevalence of HBV infection, occult hepatitis B infection (OBI) and HBV genotypes among children with clinical hepatitis. In total, 215 children with clinical hepatitis were evaluated for HBV infection. HBV serological markers and HBV DNA were analysed. OBI diagnosis and HBV genotyping was performed. HBV infection was found in 11.2% of children with clinical hepatitis. Among these HBV DNA positive-infected children, OBI was identified in 87.5% (n = 21/24) of the cases and 12.5% (n = 3/24) were positive for both HBV DNA and hepatitis B surface antigen. OBI was more frequent among children who had not been vaccinated against hepatitis B (p < 0.05) than in those who had been vaccinated. HBV genotype H was prevalent in 71% of the children followed by genotype G (8%) and genotype A (4%). In conclusion, OBI is common among Mexican children with clinical hepatitis and is associated with HBV genotype H. The results show the importance of the molecular diagnosis of HBV infection in Mexican paediatric patients with clinical hepatitis and emphasise the necessity of reinforcing hepatitis B vaccination in children.

Hepatitis B virus infection and immunopathogenesis in a humanized mouse model: induction of human-specific liver fibrosis and M2-like macrophages

The mechanisms of chronic HBV infection and immunopathogenesis are poorly understood due to a lack of a robust small animal model. Here we report the development of a humanized mouse model with both human immune system and human liver cells by reconstituting the immunodeficient A2/NSG (NOD.Cg-Prkdc(scid) Il2rg(tm1Wjl)/SzJ mice with human HLA-A2 transgene) with human hematopoietic stem cells and liver progenitor cells (A2/NSG-hu HSC/Hep mice). The A2/NSG-hu HSC/Hep mouse supported HBV infection and approximately 75% of HBV infected mice established persistent infection for at least 4 months. We detected human immune responses, albeit impaired in the liver, chronic liver inflammation and liver fibrosis in infected animals. An HBV neutralizing antibody efficiently inhibited HBV infection and associated liver diseases in humanized mice. In addition, we found that the HBV mediated liver disease was associated with high level of infiltrated human macrophages with M2-like activation phenotype. Importantly, similar M2-like macrophage accumulation was confirmed in chronic hepatitis B patients with liver diseases. Furthermore, gene expression analysis showed that induction of M2-like macrophage in the liver is associated with accelerated liver fibrosis and necrosis in patients with acute HBV-induced liver failure. Lastly, we demonstrate that HBV promotes M2-like activation in both M1 and M2 macrophages in cell culture studies. Our study demonstrates that the A2/NSG-hu HSC/Hep mouse model is valuable in studying HBV infection, human immune responses and associated liver diseases. Furthermore, results from this study suggest a critical role for macrophage polarization in hepatitis B virus-induced immune impairment and liver pathology.

Impact of IL-28B polymorphisms on pegylated interferon plus ribavirin treatment response in children and adolescents infected with HCV genotypes 1 and 4

IL-28B polymorphisms are predictors of response to therapy in adults infected with hepatitis C. We do not know whether they are markers of response to therapy in children and adolescents. The aim of this study was to determine whether single-nucleotide polymorphisms (SNPs) in the IL-28B gene could influence the probability of response to therapy compared with other known baseline prognostic factors and correlate with clinical findings in pediatric patients infected with hepatitis C virus (HCV) genotypes 1 or 4. We determined three SNPs of IL-28B (rs12979860, rs12980275, and rs8099917) in 82 patients with chronic HCV infection treated with pegylated interferon alpha and ribavirin (peg-IFNα/RBV). Treatment response and clinical data were analyzed. Overall, sustained virological response (SVR) was achieved by 45 % of patients infected with difficult-to-treat HCV genotypes 1 and 4. Except for IL-28B polymorphisms, there was no association of SVR with any other clinical data. IL-28B rs12979860 CC [odds ratio (OR), 6.81; p = 0.001] and rs8099917 TT (OR, 3.14; p = 0.013) genotypes were associated with higher SVR rates. IL-28B rs12980275 was not significantly associated with SVR (p = 0.058). Only the distribution between CC and CT-TT genotypes of rs12979860 significantly differentiated patients achieving early virological response (EVR) (OR, 10.0; p = 0.011). Children with the rs12979860 CC genotype had significantly higher baseline viral load compared with CT-TT patients (p = 0.010). In children and adolescents chronically infected with HCV genotypes 1 and 4, IL-28B rs12979860 and rs8099917 polymorphisms were the only predictors of response to peg-IFN/RBV.

Chronic hepatitis B virus (HBV) infection in children: 25 years' experience

Whereas e-seroconversion represents the loss of hepatitis B e-antigen (HBeAg) followed by gain of antibody to HBeAg (anti-HBe), 'inactive chronic infection' extends this concept to include e-seroconversion with decreased serum viral load and biochemical remission. These events must be well-characterized before treatment outcomes can be evaluated. We examined the rates of e-seroconversion and achievement of inactive chronic infection among children with chronic HBV infection. Children who were HBsAg positive >6 months were identified retrospectively between 1983 and 2008 from the Hospital for Sick Children Liver Clinic. Inactive chronic infection was defined as loss of HBeAg, serum ALT ≤40 IU/mL, and HBV DNA <10(6 ) IU/mL. Both e-seroconversion and achievement of inactive chronic infection were characterized using survival analysis. The effect of transmission route, treatment, age at diagnosis, ethnicity, gender and baseline ALT on these rates was evaluated with univariate and multiple regression. Of 252 HBeAg-positive cases, 59.9% had HBV-infected mothers, 77% were Asian, and 33 received interferon-α. Untreated children were younger at last follow-up (mean 14.5 vs 17.6 years), had lower ALT (median 60 vs 116 IU/mL) and had shorter follow-up (6.6 vs 9.1 years, all P < 0.002) compared to treated children. Crude e-seroconversion rate was 41.7% over 0.5-19.1 years of follow-up, and this was not affected by transmission route (P = 0.93), gender (P = 0.62) nor treatment (P = 0.08). 49% achieved inactive chronic infection by age 19 years. Being non-Asian, age at diagnosis<3 years, and ALT ≥40 IU/mL were associated with a higher rate of e-seroconversion and achieving inactive chronic infection (P < 0.0001). Almost 50% of children achieved inactive chronic infection by early adulthood.

Hepatitis C virus infection of human cytotrophoblasts cultured in vitro

Hepatitis C virus (HCV) infection in the uterus is a significant path of vertical HCV transmission. Some studies consider vertical HCV transmission in the uterus as the result of maternal blood leakage into infant blood, whereas others theorize that HCV is transmitted by the mother to the infant through cells constituting the placenta barrier. Although trophoblasts play an important role in the placenta barrier, no definitive evidence has been presented to prove that cytotrophoblasts can be infected with HCV. The current study investigated whether or not these can be infected with HCV by conducting an experiment, in which cultured human cytotrophoblasts were infected with HCV in vitro. The results were analyzed using reverse transcription polymerase chain reaction (RT-PCR), ultrastructural characteristic changes under an electron microscope, and immunoelectron microscopy. HCV RNA in the supernatant of the cultured medium of the infected group was intermittently detected during the 16-day incubation period using RT-PCR. Under an electron microscope, the ultrastructures of infected human cytotrophoblasts were markedly different from normal cells, demonstrating lysosomal hyperplasia, rough endoplasmic reticulum, decreased lipid droplets, presence of vacuoles, and the appearance of HCV-like particles. Using immunoelectron microscopy, HCV-like particles conjoined with golden granules were also observed. Based on the data, the current study concludes that HCV infects a human cytotrophoblast cultured in vitro; moreover, its ultrastructure changes dramatically upon infection.

Treatment of chronic hepatitis B and C in children

HBV and HCV are the predominant causes of chronic viral hepatitis in children and adults. The main purposes of the present review are to provide the reader with a comprehensive overview of the currently available therapies for chronic hepatitis B and C in children and to critically review the current guidelines and indications for treatment provided by the major international societies and by the consensus of expert panels. Overall, a conservative approach is generally warranted in children with chronic hepatitis B. For HCV, the high effectiveness of pegylated interferon and ribavirin in children with genotype 2 or 3 chronic infection supports the decision to treat. For genotype 1 infection the encouraging results of the use of direct antiviral agents in adults suggest a more conservative approach.

Current treatment options and response rates in children with chronic hepatitis C

Vertical transmission has become the most common mode of transmission of hepatitis C virus (HCV) in children. The rate of perinatal transmission from an HCV-infected mother to her child ranges from 2% to 5% and the prevalence of HCV in children in developed countries ranges between 0.1% and 0.4%. Spontaneous viral clearance seems to be dependent on the genotype and has been reported between 2.4%-25%. For chronically infected patients, treatment with recombinant polyethylene glycol (PEG)-interferon α-2b and daily ribavirin has now been approved as standard treatment for children 2-17 years of age. In five large prospective studies, a total of 318 children and adolescents aged 3-17 years were treated either with subcutaneous PEG-interferon α-2b at a dose of 1-1.5 μg/kg or 60 μg/m² once a week in combination with oral ribavirin (15 mg/kg per day) or PEG-interferon α-2a with ribavirin. Subjects with genotype 1 and 4 received the medication for 48 wk and individuals with genotype 2 and 3 mainly for 24 wk. Overall sustained viral response (SVR) was achieved in 193/318 (60.7%) of treated patients. Stratified for genotype; 120/234 (51%) with genotype 1, 68/73 (93%) with genotype 2/3, and 6/11 (55%) with genotype 4 showed SVR. Relapse rate was between 7.7% and 17%. Overall, treatment was well tolerated; however, notable side effects were present in approximately 20%. According to recent experiences in the treatment of chronic hepatitis C in children and adolescents, a combination of PEG-interferon α with ribavirin has been found to be well tolerated and highly efficacious, particularly in individuals with genotype 2/3. Thus, this treatment can be recommended as standard of care until more effective treatment options will become available for genotype 1 patients.

Immunogenicity of hepatitis A vaccine in children with celiac disease

OBJECTIVES

The response to hepatitis A vaccine has not been studied in children with celiac disease (CD). The aim of the present study was to evaluate the immunogenicity of an inactivated hepatitis A virus (HAV) vaccine and the effect of the human leukocyte antigen (HLA) type on immunogenicity in children with CD.

PATIENTS AND METHODS

Thirty-three patients with CD and 62 healthy controls were enrolled in the study. Inactivated HAV vaccine (Havrix; GlaxoSmithKline Biologicals, Rixensart, Belgium) containing 720 enzyme-linked immunosorbent assay units of alum-adsorbed hepatitis A antigen was administered intramuscularly in a 2-dose schedule at 0 and 6 months. Seroconversion rates and antibody titers of HAV were measured at 1 and 7 months.

RESULTS

At 1 month, seroconversion rates were 78.8% and 77.4% and geometric mean titers were 50.7 and 49.9 mIU/mL in the CD and control groups, respectively (P > 0.05). At 7 months, seroconversion rates were 97% and 98.4% and geometric mean titers were 138.5 and 133 mIU/mL in the CD and control groups, respectively (P > 0.05). The most frequent HLA types were HLA-DQ2, -DR3, and -DR7 alleles in patients with CD and HLA-DQ3, -DQ6, -DR11, and -DR14 in the controls. There was no association between HLA alleles and antibody titers of hepatitis A vaccine.

CONCLUSION

Children with CD have a good immune response to hepatitis A vaccine, similar to healthy controls.

Transient elastography for assessment of fibrosis in paediatric liver disease

The prognosis and management of chronic liver diseases in children largely depend on the extent and progression of liver fibrosis, which is often the most important predictor of disease outcome, and thus influences the indication for potential therapy. Unfortunately, liver biopsy continues to be the gold standard for the staging and grading of fibrosis. Liver biopsy is an invasive and painful technique with several limitations. These limitations have led to the development of alternative noninvasive methods for the accurate assessment of fibrosis and for the maintenance of an acceptable risk/benefit ratio. In the last decades, transient elastography (TE) has received increasing consideration as a means of evaluating disease progression in paediatric chronic liver disease. TE is an accurate and reproducible methodology for identifying subjects without fibrosis or significant fibrosis, or with advanced fibrosis. In this review, we provide an outline of liver fibrosis in paediatric liver diseases, including fibrogenesis, and noninvasive techniques for the diagnosis and follow-up of fibrosis, and then focus on the characteristics of TE and on its strength in the assessment of liver fibrosis, paying particular attention to studies conducted in children.

Decline in HAV-associated fulminant hepatic failure and liver transplant in children in Argentina after the introduction of a universal hepatitis A vaccination program

INTRODUCTION

Hepatitis A virus (HAV) infection is a vaccine-preventable disease. The most severe complication in children is fulminant hepatic failure (FHF), estimated to occur in 0.4% of cases; patients with FHF often require a liver transplant (LT). Following another outbreak of HAV infection in Argentina during 2003-2004, a one-dose HAV universal immunization (UI) program was started in 2005, resulting in a reduction in the incidence of HAV infection. We have investigated the impact of HAV UI on the trends in the occurrence of FHF and LT in children.

METHODS

All pediatric cases of FHF admitted to four pediatric centers in Buenos Aires during March 1993-July 2005 were retrospectively reviewed, and data of cases during August 2005-December 2008 were collected. Information about demography, HAV infections and vaccination status, diagnostic data for FHF using the Pediatric Acute Liver Failure criteria, clinical laboratory results, encephalopathy, the severity of liver disease using the Pediatric End Stage Liver Disease score, assessment of patients on the LT waiting list using King's College Criteria for LT, treatment given for FHF (pre- and post-transplant), and clinical outcome were collected using a case report form. The frequency and outcomes of HAV-associated FHF and LT cases before and after UI were analyzed.

RESULTS

During the pre-immunization period, March 1993-July 2005, 54.6% (N = 165) of FHF cases were caused by HAV; HAV-associated FHF cases peaked during 2003-2004. During the post-immunization period, August 2005-December 2008, only 27.7% (N = 18) of FHF cases were caused by HAV infection; only one of these patients had received the HAV vaccine (one dose only). The number of HAV-associated FHF cases decreased from 2005, and no cases were reported from November 2006-December 2008. Multivariate analyses showed that the association of FHF with HAV infection rather than other etiologies decreased with increasing age (P = 0.03), UI against HAV (P = 0.002), and anti-actin antibodies (P = 0.002), and increased with increasing weight (P = 0.0004).

CONCLUSIONS

The number of children with HAV-associated FHF in Argentina has strongly decreased since the initiation of the UI program. Further monitoring is required to confirm the long-term health and economic benefits of UI against HAV infection.

Liver fibrosis in paediatric liver diseases

Numerous paediatric liver diseases from different origins may be complicated by development of liver fibrosis and progression to cirrhosis. Although fibrogenesis, which represents a major driving force for the development of liver fibrosis, has common tracts whatever the aetiology, liver fibrosis has different histopathological patterns in paediatric liver disease. In these diseases management choices may depend upon the stage of liver fibrosis. Thus, the accurate estimation of histological pattern of liver fibrosis is important for the prevention of the subsequent complications. Liver biopsy has long been considered as a gold standard diagnostic method for assessing liver fibrosis. However, due to its several disadvantages, in the last decades alternative and accurate non-invasive means to estimate fibrosis are developed. In this review, we characterised the most frequent histological patterns of liver fibrosis in paediatric liver diseases. Furthermore, we describe use of liver biopsy in diagnosis and staging of liver fibrosis, list the alternative non-invasive techniques that have an emerging role in the assessment of liver fibrosis, and propose a management algorithm.

Viral hepatitis: retrospective review in a canadian pediatric hospital

Introduction. Clinical presentation of viral hepatitis ranges from mild symptoms to fulminant hepatitis. Our aim is to describe clinical presentation and outcomes of children with viral hepatitis from the Eastern Ontario/Western Quebec regions of Canada. Methods. Retrospective chart review of children diagnosed with viral hepatitis at our institution from January 1, 1998, to December 31, 2007. Results. There were 261 charts reviewed, only 64 had a confirmed viral etiology: 34 (53%) hepatitis B (HBV), 16 (25%) hepatitis C (HCV), 4 (6.3%) hepatitis A (HAV), 7 (11%) cytomegalovirus (CMV), and 3 (4.7%) Epstein-Barr virus (EBV). Children with HBV presented at a mean age of 6.4 ± 4.6 years. Spontaneous seroconversion (appearance of HBVeAb and loss of HBVeAg) occurred in 21/34 (61.7%). Children with acute hepatitis (HAV, CMV, and EBV) presented with mild abdominal pain, jaundice, and fevers. Overall outcome was excellent. Conclusion. Acute and chronic hepatitis in children has a benign course; moreover, HBV spontaneous seroconversion is common in pediatric patients.