Children with hepatitis C

Vertically acquired hepatitis C virus infection: Correlates of transmission and disease progression

The worldwide prevalence of hepatitis C virus (HCV) infection in children is 0.05%-0.4% in developed countries and 2%-5% in resource-limited settings, where inadequately tested blood products or un-sterile medical injections still remain important routes of infection. After the screening of blood donors, mother-to-child transmission (MTCT) of HCV has become the leading cause of pediatric infection, at a rate of 5%. Maternal HIV co-infection is a significant risk factor for MTCT and anti-HIV therapy during pregnancy seemingly can reduce the transmission rate of both viruses. Conversely, a high maternal viral load is an important, but not preventable risk factor, because at present no anti-HCV treatment can be administered to pregnant women to block viral replication. Caution is needed in adopting obstetric procedures, such as amniocentesis or internal fetal monitoring, that can favor fetal exposure to HCV contaminated maternal blood, though evidence is lacking on the real risk of single obstetric practices. Mode of delivery and type of feeding do not represent significant risk factors for MTCT. Therefore, there is no reason to offer elective caesarean section or discourage breast-feeding to HCV infected parturients. Information on the natural history of vertical HCV infection is limited. The primary infection is asymptomatic in infants. At least one quarter of infected children shows a spontaneous viral clearance (SVC) that usually occurs within 6 years of life. IL-28B polymorphims and genotype 3 infection have been associated with greater chances of SVC. In general, HCV progression is mild or moderate in children with chronic infection who grow regularly, though cases with marked liver fibrosis or hepatic failure have been described. Non-organ specific autoantibodies and cryoglobulins are frequently found in children with chronic infection, but autoimmune diseases or HCV associated extrahepatic manifestations are rare.

Infectious Diseases and the Kidney in Children

The kidney is involved in a wide range of bacterial, viral, fungal, and parasitic diseases. In most systemic infections, renal involvement is a minor component of the illness, but in some, renal failure may be the presenting feature and the major problem in management. Although individual infectious processes may have a predilection to involve the renal vasculature, glomeruli, interstitium, or collecting systems, a purely anatomic approach to the classification of infectious diseases affecting the kidney is rarely helpful because most infections may involve several different aspects of renal function. In this chapter, a microbiological classification of the organisms affecting the kidney is adopted. Although they are important causes of renal dysfunction in infectious diseases, urinary tract infections and hemolytic uremic syndrome (HUS) are not discussed in detail because they are considered separately in chapters XX and XX, respectively.

Natural history of vertically acquired HCV infection and associated autoimmune phenomena

The natural history of vertically acquired HCV infection is ill defined. The aim of this study was to outline the natural course of vertical HCV infection in a cohort of untreated children, including rate of spontaneous viral clearance, frequency and features of HCV-related autoimmune disorders. Children with vertical HCV infection were prospectively followed from the first month of life with regular clinical and laboratory assessments. Statistical analysis was performed using Prism 5.0. Forty-five children (median age 12 years, interquartile range 6.9-15.5) were studied. Genotype 1 was predominant (53.3 %). Spontaneous viral clearance was achieved by 12 patients (26.7 %) and associated with genotype 3. Alanine-amino-transferase levels were increased in most children in the first 2 years of life with higher values in those who later cleared the infection. All children were asymptomatic for liver disease. Transient elastography (32 patients) showed mild or moderate fibrosis in nine and two cases, respectively. Non-organ-specific autoantibodies were detected in 24 children (53.3 %) independently of viremia; of these, one developed type-1 diabetes. Cryoglobulinemia was associated with genotype 1 infection and found in 15 subjects (33.3 %): two had low C4 levels and persistent proteinuria.

CONCLUSIONS

Vertically acquired HCV infection may result in spontaneous clearance in up to 27 % of children. Resolution of infection is higher with genotype 3, usually occurs in preschool age and persists over time. Chronic infection is generally asymptomatic, although hepatomegaly and mild fibrosis may develop. Autoantibodies and cryoglobulins are frequent, whereas the associated clinical manifestations are rare.

Treatment options for chronic hepatitis B and C infection in children

There has been a dramatic increase in treatment options for both chronic hepatitis B (CHB) and chronic hepatitis C (CHC) infection in adults over the past 5-10 years, resulting in standardized regimes for initial treatment, relapsers and even infection in the setting of recurrence post-liver transplantation. These regimes have resulted in the halting of the disease progression, reduction in the risk of hepatocellular carcinoma and removal of these infections as a contraindication for liver transplantation. However, treatment in children must be considered carefully in the context of the natural history of these infections and host factors, particularly the immunological mileu, which may affect response to therapy. The as yet unknown long-term effects of medications must also be balanced with the probability of significant life-long morbidity or mortality from chronic hepatitis and its complications. Furthermore, the development of drug resistance, particularly in the case of CHB, has significant implications for the pediatric patient who may exhaust effective therapeutic options at a relatively young age. For these reasons, initiation of therapy must be based on sound criteria. Based on the current data, we recommend that therapy should be offered to children with CHB who have an elevation in alanine aminotransferase (>2-3 x upper limit of normal) for more than 6 months. Therapy with interferon-alpha should be offered in the majority of cases with the aim of immune clearance as measured by early antigen seroconversion. By contrast, treatment indication for CHC in children remains controversial. If used, combination therapy with pegylated interferon and ribavirin is likely to produce the highest rates of sustained viral response.

Burden of pediatric hepatitis C

Hepatitis C virus (HCV) is a major health burden infecting 170-210 million people worldwide. Additional 3-4 millions are newly-infected annually. Prevalence of pediatric infection varies from 0.05%-0.36% in the United States and Europe; up to 1.8%-5.8% in some developing countries. The highest prevalence occurs in Egypt, sub-Saharan Africa, Amazon basin and Mongolia. HCV has been present in some populations for several centuries, notably genotypes 1 and 2 in West Africa. Parenteral anti-schistosomal therapy practiced in the 1960s until the early 1980s had spread HCV infection throughout Egypt. Parenteral acquisition of HCV remains a major route for infection among Egyptian children. Insufficient screening of transfusions, unsterilized injection equipment and re-used needles and syringes continue to be major routes of HCV transmission in developing countries, whereas vertical transmission and adolescent high-risk behaviors (e.g., injection drug abuse) are the major routes in developed countries. The risk of vertical transmission from an infected mother to her unborn/newborn infant is approximately 5%. Early stages of HCV infection in children do not lead to marked impairment in the quality of life nor to cognitive, behavioral or emotional dysfunction; however, caregiver stress and family system strain may occur. HCV slowly progresses to serious complications as cirrhosis (1%-2%) and hepatocellular carcinoma (HCC) especially in the presence of risk factors as hemolytic anemias, obesity, treated malignancy, and concomitant human immune deficiency and/or hepatitis B virus co-infection. HCV vaccine remains elusive to date. Understanding the immune mechanisms in patients who successfully cleared the infection is essential for vaccine development. The pediatric standard of care treatment consists of pegylated interferon-α 2a or b plus ribavirin for 24-48 wk. The new oral direct acting antivirals, approved for adults, need further evaluation in children. Sustained virologic response varies depending on the viral load, genotype, duration of infection, degree of aminotransferase elevation, adiposity and single nucleotide polymorphisms of interleukin (IL)-28B locus. The goals of treatment in individual patients are virus eradication, prevention of cirrhosis and HCC, and removing stigmatization; meanwhile the overall goal is decreasing the global burden of HCV. IL-28B polymorphisms have been also associated with spontaneous clearance of vertically acquired HCV infection. The worldwide economic burden of HCV for children, families and countries is estimated to be hundreds of millions of US dollars per year. The United States, alone, is estimated to spend 199-336 million dollars in screening, monitoring and treatment during one decade. The emotional burden of having an HCV infected child in a family is more difficult to estimate.

Dynamic changes in viral population structure and compartmentalization during chronic hepatitis C virus infection in children

Classic phylogenetic and modern population-based clustering methods were used to analyze hepatitis C virus (HCV) evolution in plasma and to assess viral compartmentalization within peripheral blood mononuclear cells (PBMCs) in 6 children during 3.2-9.6yr of follow-up. Population structure analysis of cloned amplicons encompassing hypervariable region 1 led to the distinction of two evolutionary patterns, one highly divergent and another one genetically homogeneous. Viral adaptability was reflected by co-evolution of viral communities switching rapidly from one to another in the context of divergence and stability associated with highly homogeneous communities which were replaced by new ones after long periods. Additionally, viral compartmentalization of HCV in PBMCs was statistically demonstrated, suggesting their role as a pool of genetic variability. Our results support the idea of a community-based structure of HCV viral populations during chronic infection and highlight a role of the PBMC compartment in the persistence of such structure.

Recruitment and retention strategies in a clinical trial for children with chronic hepatitis C infection

Successful strategies for recruitment and retention (R & R) in pediatric trials are needed. The purpose of our study was to analyze the effectiveness of R&R in a trial for children with hepatitis C. Recruitment strategies were (1) Initial (months 0-12) and (2) extra effort (months 13-18). Initial strategies enrolled 70/114 (61%) of patients. Extra effort strategies included: (1) radio broadcasts, (2) contact with adult hepatologists, (3) dissemination of study material and (4) modification of the exclusion criteria. The overall retention rate was 84% at 2 years. Lessons learned will be valuable in designing future pediatric trials.

Pathogenesis of hepatitis C during pregnancy and childhood

The worldwide prevalence of HCV infection is between 1% and 8% in pregnant women and between 0.05% and 5% in children. Yet the pathogenesis of hepatitis C during pregnancy and in the neonatal period remains poorly understood. Mother-to-child transmission (MTCT), a leading cause of pediatric HCV infection, takes place at a rate of <10%. Factors that increase the risk of MTCT include high maternal HCV viral load and coinfection with HIV-1 but, intriguingly, not breastfeeding and mode of delivery. Pharmacological prevention of MTCT is not possible at the present time because both pegylated interferon alfa and ribavirin are contraindicated for use in pregnancy and during the neonatal period. However, this may change with the recent introduction of direct acting antiviral agents. This review summarizes what is currently known about HCV infection during pregnancy and childhood. Particular emphasis is placed on how pregnancy-associated immune modulation may influence the progression of HCV disease and impact MTCT, and on the differential evolution of perinatally acquired HCV infection in children. Taken together, these developments provide insights into the pathogenesis of hepatitis C and may inform strategies to prevent the transmission of HCV from mother to child.

Treatment and follow up of children with chronic hepatitis C in Albania

BACKGROUND

Treatment of Hepatitis C in children has a better outcome than in adults, and for this reason the treatment had different views. However, in pediatric age hepatitis C is seen to have an evolution towards chronicity. Today is a normal option to treat chronic hepatitis C as early as possible according to certain criteria. The aim of this study is to show the results of treatment with interferon and ribavirin and the follow-up of children diagnosed with chronic hepatitis C in our service.

PATIENTS AND METHODS

This is a prospective study which has included children 3 up to 15 years old (13 boys and 4 girls) diagnosed with chronic hepatitis C. All patients underwent a certain protocol, including liver biopsy prior to treatment. Treatment consisted in use for 48 weeks of INF α-2b, 3 MIU/m2 three times a week s/c and ribavirin 15 mg/kg orally divided bid. Two patients were treated with PEGINF α-2b with dose 1.5 mcg/kg once a week s/c and ribavirin 15 mg/kg. After the treatment all patients have stayed under our control for an average period of 24 weeks.

RESULTS

At the end of the treatment we detected a patient with HCV-RNA positive. End Treatment Viral Response was 94%. Six months later we found three patients who showed relapse of disease. Sustained Viral Response was approximately 83%

CONCLUSION

The combination therapy of interferon with Ribavirin in treatment of children with chronic hepatitis C provides a higher SVR when treatment is initiated at the earliest stages of hepatic changes. Side effects of therapy are insignificant in comparison with results obtained.

Hepatitis C virus infection during pregnancy and the newborn period--are they opportunities for treatment?

The worldwide prevalence of hepatitis C virus (HCV) infection in pregnant women is estimated to be between 1 and 8% and in children between 0.05% and 5%. While parenteral transmission is still common in children living in developing countries, perinatal transmission is now the leading cause of HCV transmission in developed countries. The absence of an HCV vaccine or approved therapy during pregnancy means that prevention of vertical transmission is still not possible. However, a low vertical transmission rate of 3-5%, a high rate of spontaneous clearance (25-50%) and delayed morbidity have resulted in HCV being overlooked in pregnant women and their infants. Yet a study of the natural history in mothers and children demonstrates that the prognosis of HCV can vary greatly and should be taken seriously. Factors known to increase the risk of perinatal transmission include HIV coinfection and higher maternal viral loads, while elective C-section and withholding breastfeeding have not been demonstrated to reduce vertical transmission. Current guidelines for the diagnosis of persistent perinatal infection require a positive anti-HCV test in infants born to infected mothers after 12 months or two positive HCV RNA tests at least 6 months apart. Current HCV treatment options using pegylated interferon and ribavirin are both unsuitable for use in pregnancy and infancy. However, new agents currently in preclinical phases of development, along with the recently identified association between single-nucleotide polymorphisms within the IL28 gene and treatment response, may serve to create a therapeutic window for these patients.

Hepatitis C virus quasispecies in chronically infected children subjected to interferon-ribavirin therapy

Accumulating evidence suggests that certain features of hepatitis C virus (HCV), especially its high genetic variability, might be responsible for the low efficiency of anti-HCV treatment. Here, we present a bioinformatic analysis of HCV-1a populations isolated from 23 children with chronic hepatitis C (CHC) subjected to interferon-ribavirin therapy. The structures of the viral quasispecies were established based on a 132-amino-acid sequence derived from E1/E2 protein, including hypervariable region 1 (HVR1). Two types of HCV populations were identified. The first type, found in non-responders, contained a small number of closely related variants. The second type, characteristic for sustained responders, was composed of a large number of distantly associated equal-rank variants. Comparison of 445 HVR1 sequences showed that a significant number of variants present in non-responding patients are closely related, suggesting that certain, still unidentified properties of the pathogen may be key factors determining the result of CHC treatment.

Innate immune function in placenta and cord blood of hepatitis C--seropositive mother-infant dyads

Vertical transmission accounts for the majority of pediatric cases of hepatitis C viral (HCV) infection. In contrast to the adult population who develop persistent viremia in ∼80% of cases following exposure, the rate of mother-to-child transmission (2–6%) is strikingly low. Protection from vertical transmission likely requires the coordination of multiple components of the immune system. Placenta and decidua provide a direct connection between mother and infant. We hypothesized that innate immune responses would differ across the three compartments (decidua, placenta and cord blood) and that hepatitis C exposure would modify innate immunity in these tissues. The study was comprised of HCV-infected and healthy control mother and infant pairs from whom cord blood, placenta and decidua were collected with isolation of mononuclear cells. Multiparameter flow cytometry was performed to assess the phenotype, intracellular cytokine production and cytotoxicity of the cells. In keeping with a model where the maternal-fetal interface provides antiviral protection, we found a gradient in proportional frequencies of NKT and γδ-T cells being higher in placenta than cord blood. Cytotoxicity of NK and NKT cells was enhanced in placenta and placental NKT cytotoxicity was further increased by HCV infection. HCV exposure had multiple effects on innate cells including a decrease in activation markers (CD69, TRAIL and NKp44) on NK cells and a decrease in plasmacytoid dendritic cells in both placenta and cord blood of exposed infants. In summary, the placenta represents an active innate immunological organ that provides antiviral protection against HCV transmission in the majority of cases; the increased incidence in preterm labor previously described in HCV-seropositive mothers may be related to enhanced cytotoxicity of NKT cells.

SAFETY study: alanine aminotransferase cutoff values are set too high for reliable detection of pediatric chronic liver disease

BACKGROUND & AIMS

The appropriate alanine aminotransferase (ALT) threshold value to use for diagnosis of chronic liver disease in children is unknown. We sought to develop gender-specific, biology-based, pediatric ALT thresholds.

METHODS

The Screening ALT for Elevation in Today's Youth (SAFETY) study collected observational data from acute care children's hospitals, the National Health and Nutrition Examination Survey (NHANES, 1999-2006), overweight children with and without non-alcoholic fatty liver disease (NAFLD), and children with chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections. The study compared the sensitivity and specificity of ALT thresholds currently used by children's hospitals vs study-derived, gender-specific, biology-based, ALT thresholds for detecting children with NAFLD, HCV, or HBV.

RESULTS

The median upper limit of ALT at children's hospitals was 53 U/L (range, 30-90 U/L). The 95th percentile levels for ALT in healthy weight, metabolically normal, liver disease-free, NHANES pediatric participants were 25.8 U/L (boys) and 22.1 U/L (girls). The concordance statistics of these NHANES-derived thresholds for liver disease detection were 0.85 (95% confidence interval [CI]: 0.74-0.96) in boys and 0.91 (95% CI: 0.83-0.99) in girls for NAFLD, 0.80 (95% CI: 0.70-0.91) in boys and 0.79 (95% CI: 0.69-0.89) in girls for HBV, and 0.86 (95% CI: 0.77-0.95) in boys and 0.84 (95% CI: 0.75-0.93) in girls for HCV. Using current children's hospitals ALT thresholds, the median sensitivity for detection of NAFLD, HBV, and HCV ranged from 32% to 48%; median specificity was 92% (boys) and 96% (girls). Using NHANES-derived thresholds, the sensitivities were 72% (boys) and 82% (girls); specificities were 79% (boys) and 85% (girls).

CONCLUSIONS

The upper limit of ALT used in children's hospitals varies widely and is set too high to reliably detect chronic liver disease. Biology-based thresholds provide higher sensitivity and only slightly less specificity. Clinical guidelines for use of screening ALT and exclusion criteria for clinical trials should be modified.

Treatment of hepatitis C in children

Hepatitis C affects 4-10% of children born to infected mothers, and 80% of them develop chronic infection. Most patients with chronic hepatitis C virus infection are asymptomatic, with persistent or intermittent biochemical abnormalities. Severe liver disease may develop 10 years after onset of infection, with a less than 2% overall risk during the pediatric age. Available therapies have no contraindication in children if otherwise healthy. The US FDA and EMEA have recently approved combined pegylated-IFN-alpha 2b plus ribavirin treatment for children, who should be over 3 years of age in order to avoid severe side effects. Experiences in pilot trials and international studies indicate a response rate of 50% in genotype 1 patients, and more than 90% in genotype 2 or 3 patients, indicating resolution of chronic disease.

[Indication of determination of antibodies against hepatitis C and A viruses in the protocol for the care of young immigrants]

OBJECTIVES

To evaluate systematic determination of antibodies against hepatitis C virus (HCV) and hepatitis A virus (HAV) within the protocols for the care of young immigrants (PCYI).

METHODS

We performed a descriptive, cross-sectional, multicenter study. Antibodies against HCV and HAV were determined in children aged from 6 months to 15 years from low-income countries who had immigrated to Spain less than 12 months previously. Age, sex and country of origin were registered. The cost of vaccinating all immigrant children (with the HA vaccine and HA-HB vaccine, public health price and retail price) without screening was compared with that of vaccinating non-immune children only.

RESULTS

HCV antibodies were determined in 1055 children and only one was positive [0.09% (95% CI: 0-0.53%)]. HAV antibodies were determined in 992 children and, overall, 38% were positive (95% CI: 35.0-41.1). Distribution by country of origin was as follows: Central and South America (n=352) 34.9%, Maghreb (n=246) 44.7%, and India, Pakistan and Bangladesh (n=162) 58.6%. According to the children's age, country of origin, and the price of the vaccine used, HAV antibody determination in young immigrants before HAV vaccination is efficient.

CONCLUSIONS

Because of the low prevalence of HCV antibodies in the pediatric immigrant population, systematic determination is not warranted. Evaluating HAV antibodies in each immigrant child could increase the efficiency of PCYI.

Evaluation of FibroTest-ActiTest in children with chronic hepatitis C virus infection

FibroTest-ActiTest (FT-AT) has been validated in adults with chronic hepatitis C virus (HCV) infection as a noninvasive alternative to liver biopsy (LB), but there are few data of its use in children. The objective of the present study was to evaluate FT-AT in children with HCV infection and to compare FT-AT analysis with liver histology. A total of 43 serum samples from 38 children with chronic HCV infection were analyzed retrospectively. Histological evaluation was performed according to the METAVIR scoring system. In 16 of the children, 21 serum samples were tested with FT-AT and compared to 21 LB (serum/LB pairs) in nontransplanted and liver-transplanted children. FT-AT was also measured in 22 infected children without LB and in 50 healthy controls. FT-AT values in controls were comparable to those of healthy adults, validating the adult FT-AT parameters in children. In most infected children (74%), the FT-AT score was <or = A1-F1. Concordance between FT-AT and METAVIR scores was found in 10 pairs and discordance in 11. FT-AT/METAVIR concordance was better in non-transplanted (8/13 pairs, 62%) than in transplanted (2/8 pairs, 25%) children. A prospective evaluation of FT-AT in non-transplanted children with chronic HCV infection would be worthwhile in future.

Acute hepatitis C: prevention and treatment

HCV can cause acute or chronic hepatitis and is a health problem all over the world. It is one of the leading causes of cirrhosis and hepatocellular carcinoma, and is a common indication for liver transplantation. Unrecognized patients with HCV infection may transmit the virus to uninfected people. The acute form of the disease leads to chronic hepatitis in the majority of cases. Since the success rate of treatment given in the chronic phase is much lower than that given in the acute phase, recognizing acute hepatitis is critical. Although HCV is less prevalent since 1990s in the Western world after improved blood-donor screening programs, needle-exchange facilities and education among intravenous drug users, it is still endemic in some regions, including African countries, Egypt, Taiwan, China and Japan. Acute HCV infection may be a challenge for the clinician; since it is often asymptomatic, detection and diagnosis are usually difficult. After an incubation period of 7 weeks (2-12 weeks), only a minority of patients (10-15%) report symptoms. The spontaneous clearance of the virus is more frequent primarily during the first 3 months of clinical onset of the disease, but may occur anytime during the 6 months of acute infection. This spontaneous resolution seems to be more frequent in symptomatic cases. Viremia persisting more than 6 months is accepted as chronic infection. The virus is transmitted more frequently through infected blood or body fluids. Detection of antibodies against HCV is not a reliable method of diagnosing acute HCV infection since the appearance of antibodies against HCV can be delayed in up to 30% of patients at the onset of symptoms. Thus, the diagnosis of acute hepatitis C relies on the qualitative detection of HCV RNA, which may appear as early as 1-2 weeks after exposure quickly followed by highly elevated alanine aminotransferase. After a follow-up period of 8-12 weeks for allowing spontaneous resolution, treatment should be initiated. Pegylated interferon monotherapy for 24 weeks seems effective, and the therapy can be individualized according to the characteristics of the patient.

Prevention of viral hepatitis (B and C) reassessed

As hepatitis B and C share modes of transmission, their combined occurrence is not uncommon, particularly in areas where both viruses are endemic and in individuals at high-risk of parenteral infection. Both viral hepatitis infections form an important global public health problem, responsible for over half a billion chronic infections worldwide. Their distinctive characteristics impact upon their epidemiology, transmission, and the success of the different prevention strategies. Since several decades a safe and effective vaccine has been available to prevent hepatitis B virus (HBV) infection. Universal vaccination is the cornerstone of global HBV control. Despite major success, vaccine uptake is hampered, and increasing efforts are required to eliminate acute and chronic hepatitis B. Unlike hepatitis C and HIV, HBV has not captured sufficient attention from policymakers, advocacy groups, or the general public: a major challenge for the future. Although progress has been made in the development of an hepatitis C vaccine, short-term successes are not expected. Even without a vaccine, successes can be reported in the field of hepatitis C due to e.g. implementation of universal precautionary measures in health-care settings, screening of blood and blood products, and identification and counselling of infected people. Despite important efforts, transmission in injecting drug users is increasing.

Hepatitis C virus infection among children in aboriginal areas in Taiwan

The prevalence of hepatitis C virus (HCV) infection among adults in aboriginal areas has been shown to be higher than in urban areas in Taiwan. Whether the prevalence of HCV infection is also higher among children in aboriginal areas remains unclear. In total, 1176 schoolchildren in four aboriginal areas were invited to participate in the study. All children were tested for serum antibodies to HCV (anti-HCV) and liver enzymes. The age range of children was 6-13 years. Another 606 sex- and age-matched schoolchildren from an urban area served as controls. There was no statistically significant difference in prevalence of anti-HCV between aboriginal and Han Chinese students in aboriginal areas. The prevalence of anti-HCV was 0.3% (4/1176) in aboriginal areas, which was similar to the prevalence of 0% (0/606) in the urban area. The four anti-HCV seropositive aboriginal children were all negative for HCV RNA. Our data suggest that the high prevalence of anti-HCV among aboriginal adults might be due to subsequent exposure to risk factors after school age.

Changing prevalence of hepatitis C virus infection among teenagers in an endemic area in Taiwan

Tzukuan Township in Taiwan has been reported to be an endemic area for hepatitis C virus (HCV) infection both in adults and adolescents. The maritime part of the township carries a higher prevalence than the non-maritime part and, as a consequence, several public education strategies have been introduced during the past decade. The current follow-up study aimed to clarify the changing prevalence of HCV infection among teenagers in the endemic maritime part of Tzukuan. In addition to viral hepatitis markers and biochemical profiles, we compared the epidemiological characteristics of 887 and 394 teenagers (aged 13-16 years) from the maritime part enrolled in 1995 and 2005, respectively. Compared with the results of surveillance in 1995, the prevalence of anti-HCV seropositivity (1.0% vs. 2.8%; P=0.045) and HCV RNA (0.5% vs. 2.3%; P=0.026) had decreased significantly by 2005. Transfusions and anti-HCV-positive families were the main risk factors amongst the 25 anti-HCV-positive teenagers in 1995, and became non-significant amongst the four anti-HCV-positive teenagers in 2005. In conclusion, the seroprevalence of HCV infection has significantly decreased after one decade of intervention among the teenage population in this endemic area.

Chronic hepatitis C infection in a patient with bone marrow hypoplasia

Chronic hepatitis C virus (HCV) infection is associated with multifarious extra-hepatic manifestations; the most described and discussed being mixed cryoglobulinemia which is strongly related to B-cell lymphoproliferative disorders (LPDs). We present a case of chronic HCV infection and mixed cryoglobulinemia, with minimal liver involvement. The case is a 53-year-old patient who was diagnosed as having bone marrow hypoplasia at the age of three. She received several blood transfusions to normalize her haemoglobin. At the age of 31, she was diagnosed with rheumatoid arthritis on account of her diffuse joint pain and inflammation, elevated rheumatoid factor (RF) and Raynaud’s phenomenon. Twenty years later, monoclonal gammopathy of IgG Lambda (one year later, changed to IgM Kappa) was detected during a routine examination. A bone marrow biopsy showed hypoplasia, Kappa positive B-lymphocytes and low-grade malignant lymphoma cells. PCR of the bone marrow aspirate was not contributory. No treatment was initiated owing to her poor bone marrow function and she is under regular follow-up.

Long-term course of chronic hepatitis C in children: from viral clearance to end-stage liver disease

BACKGROUND & AIMS

The natural course of chronic hepatitis C (CHC) in children is not well understood. The aim of this study was to assess the long-term course of CHC in a large sample of otherwise healthy children.

METHODS

From 1990 to 2005, 504 consecutive antihepatitis C virus (HCV)-positive children were enrolled at 12 centers of a national observatory and were followed up retrospectively/prospectively.

RESULTS

Putative exposure was perinatal in 283 (56.2%) cases, parenteral in 158 (31.3%), and unknown in 63 (12.5%). At baseline, 477 (94.6%) cases were HCV RNA seropositive, 118 (24.7%) of which were treated with standard interferon alpha. Ten years after putative exposure, the outcome in 359 HCV RNA-positive, untreated patients was (1) undetectable viremia in 27 (7.5%) (by Cox regression analysis, spontaneous viral clearance was independently predicted by genotype 3 [hazard ratio 6.44; 95% confidence interval: 2.7-15.5]) and (2) persistent viremia in 332 (92%) cases. Six of these 332 cases (1.8%) progressed to decompensated cirrhosis (mean age, 9.6 years). This latter group included 5 Italian children perinatally infected with genotype 1a (4 of the mothers were drug users). Thirty-three (27.9%) treated patients achieved a sustained virologic response.

CONCLUSIONS

Over the course of a decade, few children with chronic HCV infection cleared viremia spontaneously, and those who did were more likely to have genotype 3. Persistent viral replication led to end-stage liver disease in a small subgroup characterized by perinatal exposure, maternal drug use, and infection with HCV genotype 1a. Children with such features should be considered for early treatment.

The epidemiology of transfusion-associated hepatitis C in a children's hospital

BACKGROUND

Children transfused with blood and blood products before 1992 are at risk for chronic hepatitis C virus (HCV) infection. To determine the prevalence of HCV infection and risks associated with acquisition of HCV, a single-institution lookback study was performed.

STUDY DESIGN AND METHODS

A total of 5473 infants and children who received transfusions between 1982 and 1992 were identified. A control population of 600 age-, sex-, race- and zip code-matched children who did not receive transfusions with the same exclusions provided background seroprevalence data. Patients were tested for antibodies to HCV, confirmed with second generation recombinant immunoblot assay (RIBA) and when appropriate quantitative and qualitative HCV RNA by reverse transcription polymerase chain reaction (PCR). Viral persistence was assessed by serial PCR determinations for HCV RNA.

RESULTS

Of the 5473 eligible patients, 4726 were locatable and 2758 were tested. Forty-three children (1.6%) were persistently anti-HCV enzyme immunoassay (EIA)-positive, confirmed by RIBA; 39 were positive for the presence of HCV RNA. Four cleared their virus as assessed by two negative HCV PCRs 6 months apart. There was a borderline higher number of children with HCV who received fresh whole blood than those who tested HCV-negative.

CONCLUSION

Because HCV infection is generally asymptomatic, children are not identified unless they are specifically tested. We identified, enrolled, tested, and confirmed a new diagnosis of HCV infection in 43 patients. As HCV treatments become increasingly effective, it is important to identify silently infected individuals, particularly when the infection was iatrogenically induced.

Treatment of hepatitis C virus infection

Acute and chronic hepatitis C virus (HCV) infection remains a serious health problem worldwide, however, there has been advancement in the treatment of HCV infection due to standard treatment using pegylated interferon and ribavirin. The literature indicates that therapy for HCV is becoming more individualized. In addition to considering genotype and viral RNA levels before treatment, achievement of an early virologic response (EVR) and a rapid virologic response (RVR) is now possible during therapy. Moreover, problem patients, such as non-responders, relapsers, HIV or HBV co-infected patients, patients with liver cirrhosis, and pre- or post-liver transplantation patients are an increasing fraction of the patients requiring treatment. This article reviews the literature regarding standard treatments and problem patients with acute and chronic HCV infection. It also includes discussion on contraindications and side effects of treatment with interferon and ribavirin, as well as new drug development.

Treatment of hepatitis C infection

HCV infection is one of the leading causes of chronic liver disease worldwide,and it results in cirrhosis, liver failure, and HCC. As a result, hepatitis C cirrhosis has become the principal indication for liver transplantation. Ironically,HCV infection can be cured with available antiviral therapies, but only a minority of infected persons has ever been treated. The current standard of therapy isa combination of PEG-IFNalpha and ribavirin, which produces high rates of SVRs(absence of detectable HCV RNA at least 24 weeks after cessation of therapy):42% to 56% in genotype 1 and 75% to 84% in genotypes 2 and 3. Recent reports indicate that the less frequent genotypes 4, 5, and 6 also are responsive to combination therapy. Recommendations for treatment of conventional and special patient populations were reviewed in detail. Newer therapeutics that are entering clinical trials provide hope that SVRs may be possible in patients who are difficult to treat and in nonresponders to current therapy.

Evolution of hepatitis C viral quasispecies and hepatic injury in perinatally infected children followed prospectively

Perinatal infection with hepatitis C virus (HCV) is characterized by a wide range of alanine aminotransferase (ALT) levels. The mechanisms responsible for this variability are unknown. We examined whether the evolution of the HCV quasispecies was associated with different ALT profiles in perinatally infected children. Sequences within HCV envelope 1 and 2 genes, inclusive of the hypervariable region 1, the viral load, and the nascent humoral immunity were analyzed in serial serum samples from 12 perinatally infected children prospectively followed for a median of 53 months. These patients were selected to represent two different ALT patterns during the first year of life: 6 had high levels (maximum values ranging from 4.2 to 30 times the normal upper limit), and 6 had normal or slightly elevated levels (< 2 times the normal upper limit). Two patterns of viral evolution were identified according to the ALT profiles. Biochemical evidence of hepatic injury was invariably associated with a mono- or oligoclonal viral population, whereas mild or no liver damage correlated with the early emergence of a heterogeneous viral quasispecies. Consistent with selective immune pressure, amino acid changes occurred almost exclusively within the hypervariable region 1 and were temporally associated with antibody seroconversion; at this time, the difference in genetic diversity between the two groups was highly significant (P = 0.002). The two patterns of viral evolution persisted over time and did not correlate with viral load or genotype. Our study demonstrates that, in perinatally infected children, the evolution of HCV quasispecies correlates with hepatic injury. The sequences reported in this paper have been deposited in the GenBank database (accession nos. DQ 504441-DQ 507112).

The burden of hepatitis C virus infection in children: estimated direct medical costs over a 10-year period

OBJECTIVE

To quantify the burden of pediatric hepatitis C virus (HCV) disease over the coming decade.

STUDY DESIGN

Using national Census results and published and unpublished data, we constructed estimates of HCV prevalence, incidence, rate of vertical transmission, sustained viral response (SVR), and severe complications of infection. Using these figures, we generated a projection model for pediatric HCV outcomes, and we then performed a sensitivity analysis by altering the rates of fibrosis development and SVR.

RESULTS

A prevalence of 23,048 to 42,296 pediatric patients with chronic HCV combined with 7200 new cases from vertical transmission was used for further calculations. Over the next decade, estimated screening costs were 26 million US dollars, monitoring costs ranged from 117 million US dollars to 206 million US dollars, and treatment costs ranged from 56 million US dollars to 104 million US dollars.

CONCLUSIONS

To date, pediatric HCV has received relatively little attention, but it will have a significant economic impact over the next 10 years if changes in practice are not made.

Hepatitis B and C viruses in infants and young children

Advances during the past 20 years have led to a better understanding of the prevention, diagnosis, and treatment of acute and chronic hepatitis B (HBV) and hepatitis C (HCV) infections in the pediatric population. Universal vaccination and prenatal testing for HBV have decreased the incidence rate of acute HBV infections from more than 3/100,000 to 0.34/100,000 in all children. Diagnosis of chronic HBV is confirmed with positive serologic testing on two occasions at least 6 months apart. Current approved therapies with interferon alpha and lamivudine for children with chronic HBV infection have shown some efficacy, but results have been variable. In contrast, the lack of an effective HCV vaccine and the risk of mother-to-child transmission may increase the number of children with vertically acquired HCV that ultimately go on to develop liver fibrosis or cirrhosis. Diagnosis of HCV in the neonate should be postponed until after the child reaches 1 year of age because infants may have transient viremia. Treatment for HCV infected children has not been studied extensively. Peginterferon alpha-2a and Ribavirin are not currently approved for pediatric use; however, recent studies in children have shown potential benefit. More effective and less toxic therapies for young patients with HBV and HCV are needed, as are methods to interrupt perinatal transmission of HBV and HCV.

Management of hepatitis C virus in special populations: patient and treatment considerations

The most common chronic blood-borne infection in the United States is caused by hepatitis C virus. An estimated 3.9 million people (1.8%) in the United States have been infected with the hepatitis C virus, excluding certain subpopulations who are at high risk for hepatitis C virus infection. Among these subpopulations are an estimated 255,000 (15%) of prison inmates and 175,000 (22%) of homeless people. Prevalence of hepatitis C virus infection is also high among veterans (6.6% overall and even higher among homeless veterans). The single most important risk factor for hepatitis C virus infection is injection drug use; up to 90% of illicit injection drug users are infected with hepatitis C virus. This review describes the prevalence of hepatitis C virus in special populations and discusses the treatment options for patients with severe disease, transplant recipients, and patients at high risk for infection. Close monitoring and management of therapeutic side effects are required to assist these patients in adhering to therapy.

Novel insights into hepatitis C virus replication and persistence

Hepatitis C virus (HCV) is a small enveloped RNA virus that belongs to the family Flaviviridae. A hallmark of HCV is its high propensity to establish a persistent infection that in many cases leads to chronic liver disease. Molecular studies of the virus became possible with the first successful cloning of its genome in 1989. Since then, the genomic organization has been delineated, and viral proteins have been studied in some detail. In 1999, an efficient cell culture system became available that recapitulates the intracellular part of the HCV life cycle, thereby allowing detailed molecular studies of various aspects of viral RNA replication and persistence. This chapter attempts to summarize the current state of knowledge in these most actively worked on fields of HCV research.

Mother to child transmission of hepatitis C virus: rate of infection and risk factors

To determine the rate of mother-to-child transmission of hepatitis C virus (HCV) and identify risk factors associated with HCV transmission we prospectively studied 86 infants born to anti-HCV positive mothers. HCV infection was verified in all mothers before delivery and their HCV viral load was measured at or near delivery using reverse transcription polymerase reaction. For HCV genotyping the INNO-LiPA II probe assay was used. All mothers were tested for HIV infection. Possible risk factors for vertical transmission were recorded. The children were followed up for a minimum of 18 months for evidence of HCV infection, as determined by persistent HCV antibodies, or detection of HCV-RNA. Vertical transmission was restricted to infants born to viraemic mothers and the rate was 3.6% (95% CI 0.004-0.123). The HIV-infected mothers and those using drugs intravenously were more likely to transmit HCV to their children. The infected children had the same genotype as their mothers. Although the HCV RNA titre was higher in mothers who transmitted the virus than in those who did not, the viral load had borderline significance (p=0.08). Viral transmission was not influenced by mother's age, mode of delivery, genotype or type of feeding. Mother-to-child transmission of hepatitis C virus is uncommon and restricted to infants born to HCV viraemic mothers. Active drug use and HIV coinfection increase the risk for HCV vertical transmission.

Treatment options for hepatitis C infection in children

Multiple factors support treatment of hepatitis C virus (HCV) infection in children. These factors include the anticipated long duration of infection after early acquisition, relatively good tolerance of antiviral medications, and avoidance of social stigmatization. Nevertheless, careful selection of appropriate candidates for therapy is important. If a contraindication to current therapeutic agents is present, treatment should be withheld until this has resolved or until new agents are available. Children without contraindications to the medications used for HCV should undergo liver biopsy to determine the presence and degree of fibrosis. In the absence of fibrosis, treatment may be deferred. If any degree of hepatic fibrosis is present, antiviral therapy for HCV should be considered. At present, in the United States, the only therapy approved for children by the Food and Drug Administration (FDA) is a combination of interferon (IFN) alfa-2b and ribavirin. No safe therapies have been established for children younger than 3 years of age. Pegylated interferon in combination with ribavirin may be considered in adolescents older than 16 years of age who are post-pubertal, or in younger children in the context of clinical trials. Multicenter trials are currently underway to determine the safety and effectiveness of other forms of therapy for HCV infection in children.

The cost-effectiveness of elective Cesarean delivery to prevent hepatitis C transmission in HIV-coinfected women

OBJECTIVES

To determine the net health consequences, costs, and cost-effectiveness of elective Cesarean delivery (C-section) to prevent perinatal transmission of hepatitis C virus (HCV) in HIV/HCV-coinfected women with suppressed HIV RNA but detectable HCV RNA.

DESIGN

Cost-effectiveness analysis using a probabilistic decision model.

METHODS

The model compared two strategies: (i) C-section for all coinfected women with suppressed HIV RNA but detectable HCV RNA; (ii) C-section only when indicated based on fetal status. Outcomes included vertical transmission of HCV, maternal mortality, quality-adjusted life expectancy, delivery and HCV treatment costs, and incremental cost-effectiveness ratios. Data were obtained from the literature and national databases. Delivery cost data were from a hospital consortium database. Probability distributions were derived from published confidence intervals or estimated ranges, or calculated using reported sample sizes.

RESULTS

Elective C-section in coinfected women with suppressed HIV RNA but detectable HCV RNA would avoid 45 vertical HCV transmissions per 1000 deliveries and increase maternal mortality by one death per 100 000 deliveries. The incremental cost-effectiveness ratio of a recommendation for C-section versus current practice was 3900-6100 dollars per quality-adjusted life year for the mother-child pair. Results are sensitive to the efficacy of C-section in preventing transmission, the probability of vaginal delivery without a recommendation, and rates of maternal acceptance of the recommendation.

CONCLUSIONS

Assuming 2000 births/year among HIV/HCV-coinfected women in the United States, a recommendation for elective C-section in these women could avoid an additional 90 perinatal HCV transmissions per year with a risk of one maternal death in 50 years.

Chronic hepatitis C in Israeli children

Natural history, epidemiology, and histopathological features of chronic hepatis C (CHC) are well established in adults. Data on histopathological findings of CHC in children are still limited and controversial. We aimed to evaluate the histopathological features of CHC in children in Israel. We reviewed, retrospectively, 20 liver specimens from 20 children with CHC for inflammation and fibrosis, hepatocyte necrosis, fatty changes, cholestasis, bile duct damage, sinusoidal lymphocytosis, and glycogen storage. The most common histological feature was portal inflammation (95%) and lobular inflammation (70%). Sinusoidal lymphocytosis was present in 85% and glycogen storage vacuoles in 40%. Most of the children (80%) had no fibrosis, 15% had mild fibrosis and 5% moderate fibrosis. Advanced fibrosis or cirrhosis was not found. No correlation was found between the age at biopsy and any of the histological parameters. Our study shows that children with CHC have a different phenotype of liver disease with slowly progressive natural history irrespective of duration of the disease.