Perinatal hepatitis C virus infection: diagnosis and management

Clinical practice guidelines for the management of children with mother-to-child transmitted hepatitis C virus infection

BACKGROUND

The first guidelines for care of pregnant women carrying the hepatitis C virus (HCV) and their infants were published in 2005 in Japan. Since then, evidence has gradually accumulated worldwide regarding the natural course and treatment of this condition and, especially in recent years, treatment for chronic hepatitis C in adult patients has made great progress. However, the clinical practice policy for children has not been standardized, and new clinical practice guidelines for children with mother-to-child (MTC) transmitted HCV infection have become necessary.

METHODS

In the development of the current guideline, we requested cooperation from The Japanese Society for Pediatric Infectious Diseases, The Japan Society of Hepatology, and the Japan Society of Obstetrics and Gynecology. The committee members were recommended and approved by each society to participate in developing the guidelines. The guideline was also created in accordance with the Minds Guide for Practice Guideline Development. The statements were prepared by consensus-building using the Delphi method, based on the comprehensively searched academic papers and guidelines. These articles were retrieved through searching the PubMed, Cochrane Library, and the Igaku Chuo Zasshi databases.

RESULTS

Eight clinical questions (CQs) with clinical statements were developed regarding etiology (CQs 1-3), diagnosis (CQs 4 and 5), and treatment (two CQs 6 and 7). In each statement, the consensus rate, evidence level, and recommendation level were determined.

CONCLUSION

The guidelines will be helpful in the management of children with hepatitis C MTC transmission.

Low seroprevalence of hepatitis C among children at the Princess Marie Louis Children' s Hospital in Accra, Ghana

Hepatitis C is a leading cause of chronic hepatitis and causes severe health problems in areas where prevalence is high. Ghana is noted for a relatively high sero-prevalence of hepatitis C virus infection. However, there is very little data on prevalence of hepatitis C virus (HCV) among children in Ghana, and what data is available indicates very low prevalence rate. We conducted a cross-sectional study to determine the sero-prevalence and associated pre-disposing risk factor for HCV infection among children attending the Princes Marie Louis Children´s Hospital in Accra. Two hundred archived blood samples from a previous study were retrieved and tested for the presence of HCV antibodies using a dipstick test kit. Out of the 200 samples tested, one (1) tested positive for HCV antibodies giving a prevalence of 0.5% among the study group. The results show that there is potentially a very low prevalence of hepatitis C among Ghanaian children. Hence, the higher prevalence among adults usually seen is often due to infection later in life. Obtaining an appropriate vaccine early in life could thus help prevent people from getting infected in later life.

Aktuelle Therapie der chronischen Hepatitis C bei Kindern und Jugendlichen

Zur Behandlung der chronischen Hepatitis C wurden in den letzten Jahren direkt wirkende antivirale Medikamente (DAA) zugelassen und sind bei Erwachsenen etabliert. Sie machten die interferonbasierten Therapien obsolet. Auch für Kinder und Jugendliche stehen seit Kurzem einige DAA zur Verfügung, die überwiegend ab dem Alter von 3 Jahren eingesetzt werden können.

Die chronische Hepatitis C wird bei Kindern überwiegend vertikal übertragen und ist selten. Sie ist zwar zunächst eine wenig aktive und progrediente Erkrankung, kann aber im Erwachsenenalter in eine Leberzirrhose mit der Folge eines hepatozellulären Karzinoms übergehen. Die Diagnose ist mit der Bestimmung des Anti-HCV (IgM/IgG) und der HCV-RNA im Serum mit Genotypisierung leicht zu stellen. Die DAA werden oral appliziert und ausgesprochen gut toleriert. Drei Wirkstoffkombinationen stehen aktuell zur Verfügung, und 2021 wird eine weitere zugelassen. Die Heilungschancen sind mit über 95 % ausgesprochen gut und anhaltend.

Im eigenen Krankengut wurden 25 Jungen und Mädchen überwiegend mit Genotyp 1 im Alter von 4 bis 17 Jahren mit DAA behandelt. Unabhängig von der Höhe der HCV-RNA im Serum waren alle bereits nach 4 Wochen HCV-RNA negativ und erzielten einen dauerhaften Erfolg.

Die wesentliche Aufgabe ist nun, alle Kinder und Jugendlichen mit einer chronischen Hepatitis C zu identifizieren. Bei der äußerst guten Heilungschance kann davon ausgegangen werden, dass das Eradikationsziel in dieser Altersgruppe in absehbarer Zeit erreicht werden kann.

Cascade of care for children and adolescents with chronic hepatitis C. World J Gastroenterol 2021;27:1117-1131. [PMID: 33828389 PMCID: PMC8006101 DOI: 10.3748/wjg.v27.i12.1117]

Chronic hepatitis C virus (HCV) infection presents a significant global public health burden. In 2015, over 400000 deaths worldwide were attributed to HCV infection. This led the World Health Organization (WHO) in 2016 to set the ambitious goal of eliminating HCV by 2030. Adult-centered guidelines have been established in order to provide direction for healthcare professionals, allowing integration of the newest screening policies and therapeutic strategies into their practices. However, for children and adolescents, HCV is a significant, unrecognized public health problem. HCV infection rates in the United States in women of childbearing age and those who are pregnant have increased in parallel with the rising opioid epidemic. An estimated 29000 women with HCV infection gave birth each year from 2011 to 2014 in the United States, with approximately 1700 of their infants being infected with HCV. Newer HCV-specific therapeutics, namely direct acting antivirals (DAA), has brought a new and highly successful approach to treatment of hepatitis C. Recent studies have confirmed similar levels of effectiveness and safety of DAA therapies in the pediatric population. Thus, an enhanced cascade of care, which should include the population under 18 years of age, can help achieve the WHO goal by focusing on elimination in the youngest populations. This review will present an overview of the natural history, clinical features, and management of HCV in children and adolescents.

Mechanisms and evidence of vertical transmission of infections in pregnancy including SARS-CoV-2s

There remain unanswered questions concerning mother‐to‐child‐transmission of SARS‐CoV‐2. Despite reports of neonatal COVID‐19, SARS‐CoV‐2 has not been consistently isolated in perinatal samples, thus definitive proof of transplacental infection is still lacking. To address these questions, we assessed investigative tools used to confirm maternal‐fetal infection and known protective mechanisms of the placental barrier that prevent transplacental pathogen migration. Forty studies of COVID‐19 pregnancies reviewed suggest a lack of consensus on diagnostic strategy for congenital infection. Although real‐time polymerase chain reaction of neonatal swabs was universally performed, a wide range of clinical samples was screened including vaginal secretions (22.5%), amniotic fluid (35%), breast milk (22.5%) and umbilical cord blood. Neonatal COVID‐19 was reported in eight studies, two of which were based on the detection of SARS‐CoV‐2 IgM in neonatal blood. Histological examination demonstrated sparse viral particles, vascular malperfusion and inflammation in the placenta from pregnant women with COVID‐19. The paucity of placental co‐expression of ACE‐2 and TMPRSS2, two receptors involved in cytoplasmic entry of SARS‐CoV‐2, may explain its relative insensitivity to transplacental infection. Viral interactions may utilise membrane receptors other than ACE‐2 thus, tissue susceptibility may be broader than currently known. Further spatial‐temporal studies are needed to determine the true potential for transplacental migration.

Hepatitis C in 2020: A North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition Position Paper

In 1989, a collaboration between the Centers for Disease Control (CDC) and a California biotechnology company identified the hepatitis C virus (HCV, formerly known as non-A, non-B hepatitis virus) as the causative agent in the epidemic of silent posttransfusion hepatitis resulting in cirrhosis. We now know that, the HCV genome is a 9.6 kb positive, single-stranded RNA. A single open reading frame encodes a 3011 amino acid residue polyprotein that undergoes proteolysis to yield 10 individual gene products, consisting of 3 structural proteins (core and envelope glycoproteins E1 and E2) and 7 nonstructural (NS) proteins (p7, NS2, NS3, NS4A, NS4B, NS5A, and NS5B), which participate in posttranslational proteolytic processing and replication of HCV genetic material. Less than 25 years later, a new class of medications, known as direct-acting antivirals (DAAs) which target these proteins, were introduced to treat HCV infection. These highly effective antiviral agents are now approved for use in children as young as 3 years of age and have demonstrated sustained virologic responses exceeding 90% in most genotypes. Although tremendous scientific progress has been made, the incidence of acute HCV infections has increased by 4-fold since 2005, compounded in the last decade by a surge in opioid and intravenous drug use. Unfortunately, awareness of this deadly hepatotropic virus among members of the lay public remains limited. Patient education, advocacy, and counseling must, therefore, complement the availability of curative treatments against HCV infection if this virus is to be eradicated.

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.

The clinical effectiveness and cost-effectiveness of peginterferon alfa and ribavirin for the treatment of chronic hepatitis C in children and young people: a systematic review and economic evaluation

BACKGROUND

Optimal therapy for children with chronic hepatitis C is unclear. Two treatment regimens are currently licensed in children.

OBJECTIVES

To assess the clinical effectiveness and cost-effectiveness of peginterferon alfa-2a (Pegasys®, Roche) and peginterferon alfa-2b [ViraferonPeg®, Merck Sharp & Dohme (MSD)] in combination with ribavirin (RBV), within their licensed indications, for the treatment of chronic hepatitis C virus (HCV) in children and young people aged 3-17 years.

DATA SOURCES

Twelve electronic bibliographic databases, including The Cochrane Library, MEDLINE and EMBASE, were searched from inception to November 2012. Bibliographies of retrieved papers, key hepatitis C websites and symposia and manufacturers' submissions to the National Institute for Health and Care Excellence were also searched, and clinical experts were contacted.

REVIEW METHODS

Systematic reviews of clinical effectiveness and cost-effectiveness were conducted, including studies of health-related quality of life (HRQoL), following standard guidelines to ensure methodological rigour. Clinical effectiveness studies were included if they were in children and young people aged 3-17 years with chronic compensated HCV of any severity, including those with human immunodeficiency virus co-infection and those who were treatment naive or had been previously treated. Eligible interventions were peginterferon alfa-2a or peginterferon alfa-2b, each in combination with RBV, compared against best supportive care (BSC) or against each other, and study designs were randomised controlled trials (RCTs) or non-RCTs, or uncontrolled cohort studies. Outcomes included sustained virological response (SVR) and adverse events. Previously published Markov state-transition economic models of chronic HCV in adults were adapted to estimate the cost-effectiveness of peginterferon alfa-2a and -2b (in combination with RBV), compared with BSC and with one another in children. The model extrapolated the impact of SVR on life expectancy, quality-adjusted life expectancy and lifetime costs. Uncertainty was explored through probabilistic and deterministic sensitivity analyses.

RESULTS

Seven studies [two peginterferon alfa-2a and RBV (Copegus®, Roche), and five peginterferon alfa-2b and RBV (Rebetol®, MSD)] were included in the review of clinical effectiveness. Six were single-arm cohort studies and one was a RCT for which only those data for a single arm met the inclusion criteria. Overall, the studies were relatively small and of generally poor quality. SVR rates ranged from 53% to 66% (peginterferon alfa-2a) and 29% to 75% (peginterferon alfa-2b) (49% to 65% if excluding two studies with very small sample sizes). Rates of non-response and relapse were variable and adverse events were generally mild. No studies of cost-effectiveness or HRQoL in children and young people met the inclusion criteria. HRQoL, utilities and costs of treatment were therefore taken from studies of adults with chronic HCV. From this model, peginterferon alfa (-2a or -2b) in combination with RBV was more effective and had lower lifetime costs than BSC. Peginterferon alfa-2a had slightly lower lifetime costs and higher quality-adjusted life-years than peginterferon alfa-2b; therefore, peginterferon alfa-2b was dominated by peginterferon alfa-2a. Results were robust to changes in the sensitivity analyses.

LIMITATIONS

There were few good quality studies and parameter data had to be taken from adult studies, which is a limitation of the work.

CONCLUSIONS

Treatment of children and young people with peginterferon (alfa-2a or -2b) and RBV may be an effective therapy. Results from the independent Markov model suggest that peginterferon (alfa-2a or -2b) in combination with RBV is cost-effective compared with BSC. However, the available evidence is of poor quality. Future research into the impact of these treatments on growth and quality of life in children and young people is recommended.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42012002743.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Chronic Hepatitis C Infection in Children: Current Treatment and New Therapies

Viral hepatitis C is responsible for a large burden of disease worldwide. Treatment of hepatitis C infection is currently undergoing a revolution with the development of new direct acting antivirals that offer higher cure rates and fewer side effects than other medications currently available. Treatment options for children, although well-defined and evidence-based, are limited relative to adults as there are few trials regarding the use of these newly developed agents in children. With so much optimism in the development of novel therapeutic options for hepatitis C, it is timely to review and summarize the current standard of care treatment and indications for treatment of chronic hepatitis C in children. We provide here an overview of recent drug developments and their potential for use in children.

HCV transmission in industrialized countries and resource-constrained areas

HCV is a blood-borne virus transmitted by percutaneous exposure to infected blood or blood-derived body fluids. The main routes of transmission are blood transfusions, medical procedures and injection drug use. In industrialized countries, HCV transmission through blood transfusions has been virtually eliminated and iatrogenic transmission occurs only sporadically during local breaches of infection control procedures. As most new cases originate from injection drug use, harm-reduction programmes (including opiate substitution, needle exchange and health education) can greatly reduce HCV transmission. Currently, the main approach to reduce the HCV disease burden is by increasing awareness of both the public and health-care providers to hepatitis C, enhancing screening opportunities and treatment of the infected population. In resource-limited countries, the priority is reducing transmission through blood transfusions and invasive medical procedures. This approach requires training of health-care providers and also structural changes and financial investments in countries where antibody screening, disposable materials and effective sterilization procedures are not routinely available. In these countries, reducing the HCV burden has been hampered by limited access to treatment, largely owing to the cost of drugs. Access to treatment is moving up on the agenda of international and non-governmental organizations in conjunction with the future availability of highly efficacious oral drug regimens.

[Retrospective study of risk factors of vertical transmission of hepatitis C virus]

INTRODUCTION

Despite the low prevalence of paediatric HCV infection and its initial mild clinical expressiveness, chronic infection could progress into cirrhosis and/or hepatocarcinoma. It is essential to control vertical transmission. Recent studies show that up to 50% of transmissions occur within the uterus.

MATERIAL AND METHODS

[corrected] A retrospective study was conducted on 17 cases of (Hepatitis C virus) HCV infection registered over a period of 8 years. Vertical transmission risk factors were analysed, in order to introduce primary prevention.

RESULTS

Only parenteral drug addiction significantly increased the rate of HCV transmission; HIV co-infection was not a confounding factor. HCV viremia, HIV co-infection, liver dysfunction and/or duration of the infection did not appear to affect the rate of transmission. Caesarean section, amniocentesis and internal monitoring may be risk factors (not statistically significant), but not prolonged vaginal delivery after amniotic membrane rupture. Breastfeeding showed protection.

CONCLUSIONS

The effect of viremia on the risk of transmission is not clearly established, despite the importance usually attributed. Lack of viremia does not discount the risk of transmission, due to viral RNA detection can be intermittent, so it should be interpreted cautiously. Immunosuppression secondary to HIV co-infection implies a higher risk of transmission, but this effect decreases by improving immune competence by antiretroviral treatment. With regard to the birth characteristics, time after the rupture of membranes has not shown being a risk factor; being the caesarean not advisable as a good alternative to finish the pregnancy. Breastfeeding does not increase the risk, even it can be protective. This results would be justified by the low viral content of milk, its inactivation by gastric pH and its immunological benefits. Given that retrospective studies results are limited, prospective studies need to be carried out in order to improve the understanding of the role of possible risk factors and to provide a clear preventive guidelines. At the moment it is essential to control all the children born of mothers with HCV infection.

Perinatal transmission of hepatitis C virus in northern India

Data on transmission of HCV infection from mother to infant in India are limited. Between July 2006 to June 2007, women attending our hospital in the third trimester of pregnancy were screened for anti-HCV. Those testing positive for anti-HCV were tested for HCV RNA. Infants of mothers with HCV infection were followed for up to 24 months. Eight of 488 pregnant women (1.6%) tested positive for anti-HCV; of these, seven had detectable HCV RNA. Two of 7 (29%) children born to HCV-infected mothers had persistently positive HCV RNA, indicating perinatal transmission; one additional child had transient HCV positivity. Passive transfer of HCV antibodies was observed in five babies. HCV infection was detected in 1.4% of pregnant women, and perinatal transmission of HCV to newborns was detected in 29% of such cases.

Chronic hepatitis C virus infection in children

The importance of hepatitis C viral infection in the health care of children has grown in recent decades. More is now known about the epidemiology of this infection in children and the progression of disease in the pediatric age group, and the treatment options are increasing. In this review, we update readers on the state of our understanding of hepatitis C infection in children, provide the current recommendations for monitoring and treatment, and discuss emerging therapies.

Guidelines for the Prevention and Treatment of Opportunistic Infections among HIV-exposed and HIV-infected children: recommendations from CDC, the National Institutes of Health, the HIV Medicine Association of the Infectious Diseases Society of America, the Pediatric Infectious Diseases Society, and the American Academy of Pediatrics

This report updates and combines into one document earlier versions of guidelines for preventing and treating opportunistic infections (OIs) among HIV-exposed and HIV-infected children, last published in 2002 and 2004, respectively. These guidelines are intended for use by clinicians and other health-care workers providing medical care for HIV-exposed and HIV-infected children in the United States. The guidelines discuss opportunistic pathogens that occur in the United States and one that might be acquired during international travel (i.e., malaria). Topic areas covered for each OI include a brief description of the epidemiology, clinical presentation, and diagnosis of the OI in children; prevention of exposure; prevention of disease by chemoprophylaxis and/or vaccination; discontinuation of primary prophylaxis after immune reconstitution; treatment of disease; monitoring for adverse effects during treatment; management of treatment failure; prevention of disease recurrence; and discontinuation of secondary prophylaxis after immune reconstitution. A separate document about preventing and treating of OIs among HIV-infected adults and postpubertal adolescents (Guidelines for the Prevention and Treatment of Opportunistic Infections in HIV-Infected Adults and Adolescents) was prepared by a working group of adult HIV and infectious disease specialists. The guidelines were developed by a panel of specialists in pediatric HIV infection and infectious diseases (the Pediatric Opportunistic Infections Working Group) from the U.S. government and academic institutions. For each OI, a pediatric specialist with content-matter expertise reviewed the literature for new information since the last guidelines were published; they then proposed revised recommendations at a meeting at the National Institutes of Health (NIH) in June 2007. After these presentations and discussions, the guidelines underwent further revision, with review and approval by the Working Group, and final endorsement by NIH, CDC, the HIV Medicine Association (HIVMA) of the Infectious Diseases Society of America (IDSA), the Pediatric Infectious Disease Society (PIDS), and the American Academy of Pediatrics (AAP). The recommendations are rated by a letter that indicates the strength of the recommendation and a Roman numeral that indicates the quality of the evidence supporting the recommendation so readers can ascertain how best to apply the recommendations in their practice environments. An important mode of acquisition of OIs, as well as HIV infection among children, is from their infected mother; HIV-infected women coinfected with opportunistic pathogens might be more likely than women without HIV infection to transmit these infections to their infants. In addition, HIV-infected women or HIV-infected family members coinfected with certain opportunistic pathogens might be more likely to transmit these infections horizontally to their children, resulting in increased likelihood of primary acquisition of such infections in the young child. Therefore, infections with opportunistic pathogens might affect not just HIV-infected infants but also HIV-exposed but uninfected infants who become infected by the pathogen because of transmission from HIV-infected mothers or family members with coinfections. These guidelines for treating OIs in children therefore consider treatment of infections among all children, both HIV-infected and uninfected, born to HIV-infected women. Additionally, HIV infection is increasingly seen among adolescents with perinatal infection now surviving into their teens and among youth with behaviorally acquired HIV infection. Although guidelines for postpubertal adolescents can be found in the adult OI guidelines, drug pharmacokinetics and response to treatment may differ for younger prepubertal or pubertal adolescents. Therefore, these guidelines also apply to treatment of HIV-infected youth who have not yet completed pubertal development. Major changes in the guidelines include 1) greater emphasis on the importance of antiretroviral therapy for preventing and treating OIs, especially those OIs for which no specific therapy exists; 2) information about the diagnosis and management of immune reconstitution inflammatory syndromes; 3) information about managing antiretroviral therapy in children with OIs, including potential drug--drug interactions; 4) new guidance on diagnosing of HIV infection and presumptively excluding HIV infection in infants that affect the need for initiation of prophylaxis to prevent Pneumocystis jirovecii pneumonia (PCP) in neonates; 5) updated immunization recommendations for HIV-exposed and HIV-infected children, including hepatitis A, human papillomavirus, meningococcal, and rotavirus vaccines; 6) addition of sections on aspergillosis; bartonella; human herpes virus-6, -7, and -8; malaria; and progressive multifocal leukodystrophy (PML); and 7) new recommendations on discontinuation of OI prophylaxis after immune reconstitution in children. The report includes six tables pertinent to preventing and treating OIs in children and two figures describing immunization recommendations for children aged 0--6 years and 7--18 years. Because treatment of OIs is an evolving science, and availability of new agents or clinical data on existing agents might change therapeutic options and preferences, these recommendations will be periodically updated and will be available at http://AIDSInfo.nih.gov.

Age- and sex-related reference ranges of alanine aminotransferase levels in children: European paediatric HCV network

BACKGROUND

Serum alanine aminotransferase (ALT) levels are commonly used to indicate liver damage. Although elevated levels indicate possible liver injury, abnormalities, or disease, some patients with "normal" ALT levels have minimal to mild liver disease. Recently, ALT reference ranges for adults were queried and revised ranges proposed with lower upper limits of normality. The appropriateness of current paediatric ALT reference ranges is unclear.

MATERIAL AND METHODS

Hepatitis C virus (HCV)-uninfected children from the European Paediatric HCV Network represent a large population of healthy children born to HCV-infected mothers, with ALT observations collected prospectively from birth. Linear regression identified factors associated with ALT levels while accounting for within-child repeated measurements. ALT centiles stratified by sex were calculated using maximum penalized likelihood methods and LMS software.

RESULTS

A total of 1293 HCV-uninfected children had 5011 ALT measurements during follow-up. ALT levels significantly decreased with increasing age, whilst ALT levels were significantly lower in girls than boys. Reference cutoffs representing the 95th centiles before 18 months of age were 60 U/L for boys and 55 U/L for girls, decreasing to 40 U/L for boys and 35 U/L for girls after 18 months of age.

CONCLUSIONS

These reference ranges represent a unique investigation of ALT levels in a healthy child population. We show lower and more detailed age-related cutoffs of normality than available. Additionally, we demonstrate a significant effect of sex on ALT reference ranges, which has not previously been described in children younger than 5 years of age.

Perinatal transmission of hepatitis C virus infection

In industrialized countries, hepatitis C virus (HCV) is the most common cause of chronic liver disease in children. Perinatal transmission is the leading cause of infection. Perinatal transmission is confined almost always to women with detectable HCV ribonucleic acid (RNA) in the peripheral blood by the polymerase chain reaction but all children born to women with anti-HCV antibodies should be tested for HCV. Some but not all studies found that a high concentration of serum HCV RNA is associated with a higher risk of transmission. Maternal peripheral blood mononuclear cell infection by HCV, membrane rupture of longer than 6 hr before delivery, and procedures exposing the infant to maternal blood infected with HCV during vaginal delivery are associated with an increased risk of transmission. Maternal coinfection with HCV and human immunodeficiency virus, maternal history of intravenous drug use and of HCV infection of the sexual partner of the mother predict the risk of perinatal transmission and are dependent on the peripheral blood mononuclear cell infection by HCV. Delivery by Cesarean section is not recommended in pregnant women infected with HCV. Infected mothers can breast feed safely their infants if the nipples are not damaged. A previous delivery of a child infected perinatally with HCV does not increase the risk of transmission in subsequent pregnancies. Immunogenetic factors and HCV genotypes are not related to HCV perinatal transmission. Despite an increased understanding of the risk factors involved in perinatal transmission of HCV, to date little is known about the transmission mechanisms and timing.

Management strategies for hepatitis C virus infection in children

Chronic hepatitis C virus (HCV) infection is a major cause of morbidity and mortality worldwide. Progression to cirrhosis and hepatocellular carcinoma occurs in 20% of infected adults. The natural history following childhood infection is less well defined, although cirrhosis in children is described. Since blood product screening for HCV infection was introduced in 1990, most children who acquire HCV do so by vertical transmission from an infected mother. Transmission to offspring occurs in approximately 5%. Most children with HCV infection are asymptomatic. Diagnosis is made by testing those at risk for HCV RNA by polymerase chain reaction (PCR) and HCV antibody (anti-HCV) by enzyme immunoassay (EIA). The clinical impact of HCV infection is assessed by monitoring symptoms and signs, blood testing of liver enzymes, ultrasound imaging, and by liver biopsy. Improved efficacy and tolerability of treatment strategies in adults have had a significant impact on the management of children with HCV infection. The emphasis is now on promoting awareness, early diagnosis, and treatment. Treatment strategies have evolved from monotherapy with interferon alfa (IFNalpha), to combination therapy with ribavirin. Pegylated IFNalpha is superior to conventional IFNalpha, and forms the basis of current recommendations. The genotype of HCV influences treatment efficacy. Treatment is generally well tolerated in children, although adverse effects are common. Preparation and support throughout treatment for the whole family is needed. A proportion of children with HCV infection have co-morbidity, including viral co-infection or hematologic disease. Although treatment may be contraindicated, risks and benefits must be considered before denying treatment. Anemia is more common in those with HIV co-infection, renal insufficiency, thalassemia, or cirrhosis, and may be aggravated by treatment. Children with thalassemia may have iron overload, and transfusion requirements may increase during treatment. Further refinements of combination therapy and development of new drugs are in progress. Vaccine candidates are undergoing phase I and II treatment trials.

Hepatitis C in children: recent advances

PURPOSE OF REVIEW

Hepatitis C virus infection has recently been recognized as a viral infection with the potential to cause significant complications, including cirrhosis and hepatocellular carcinoma in adults. Changes in our understanding of its natural history in children and recent advances in therapy for acute and chronic hepatitis C are reviewed.

RECENT FINDINGS

Recent work has demonstrated that, although uncommon, vertical transmission is the most frequent mode of hepatitis C acquisition in children and is enhanced in the setting of maternal co-infection with HIV. Chronic hepatitis C during childhood leads in some cases to development of advanced hepatic fibrosis, with complications including liver failure and liver cancer, which has changed our general approach to this infection. Perhaps the most significant recent advance in this area is our improved understanding of the safety and efficacy of interferon-based antiviral therapies for children with hepatitis C.

SUMMARY

Hepatitis C virus infection has reached epidemic proportions worldwide; despite its being less prevalent in children than in adults, it poses a significant clinical problem in this age group. Emerging antiviral therapies are currently in clinical trials for adult patients with hepatitis C with encouraging preliminary results, which should be extended to children.