Huey-Ling Chen

Hepatitis B Virus Infection in Children and Adolescents in a Hyperendemic Area: 15 Years after Mass Hepatitis B Vaccination

Hepatitis B virus (HBV) infection is an important cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma in many parts of the world, including Taiwan (1, 2). Up to 15% to 20% of the general population in Taiwan are chronic carriers of hepatitis B surface antigen (HBsAg) (3, 4). Most chronic carriage of HBV results from infection in early childhood, especially before 2 years of age (57). Taiwan launched the worlds first nationwide universal vaccination program in 1984 to prevent infection in the early years of life (8). In addition to decreasing the proportion of carriers and the prevalence of HBV infection in the current young generation (9), the universal vaccination program has also resulted in a decreased incidence of childhood hepatocellular carcinoma (10). To study the effect of this universal vaccination program, we conducted a series of prospective seroepidemiologic surveys in Chung-Cheng District, Taipei City, Taiwan. The first survey was conducted shortly before the mass vaccination program began in 1984 (6), followed by similar surveys in 1989 (11) and 1994 (12). We report findings that extend our follow-up observations to 199915 years after the start of the program. Methods National Vaccination Program The national program of universal HBV vaccination in Taiwan began on 1 July 1984 (8). At that time, only the newborn infants of mothers who were HBsAg carriers were vaccinated. The vaccination program was extended in June 1987 to include all newborn infants and in July 1987 to cover all children of preschool age. The program was further extended to school children, teenagers, and then adults from 1988 to 1990. Since 1991, the vaccination records of first-grade children have been checked, and children without a complete set of previous vaccinations have been given catch-up HBV vaccinations. Before July 1992, four doses of plasma-derived vaccine were administered in children before 1 week of age and again at 1, 2, and 12 months of age; after July 1992, three doses of recombinant (yeast-derived) vaccine were administered before 1 week and at 1 month and 6 months of age. Since 1984, newborns whose mothers test positive for hepatitis B e antigen (HBeAg) have also received hepatitis B immunoglobulin, 0.5 mL (100 IU), within 24 hours after birth. The vaccination program has been described in greater detail elsewhere (8, 12). We defined the vaccination coverage rate as the percentage of children receiving at least three doses of HBV vaccine. We assessed the vaccination histories of the studied population by examining their vaccination cards and by taking a history from their parents. We classified the vaccination status as unknown for persons with a missing vaccination card or a vague vaccination history. Participants From March 1999 to October 1999, serum samples were collected from 1916 children and adolescents from two groups: 1) 1357 apparently healthy persons younger than 15 years of age [721 male participants and 636 female participants], who were born after the launch of the universal vaccination program, and 2) 559 persons (297 male participants and 262 female participants) 15 to 20 years of age, who were born before universal vaccination. We recruited participants for the baseline and follow-up seroepidemiologic studies in Chung-Cheng District, Taipei City. In 1999, Chung-Cheng had a population of 165 388 citizens; 35 005 of the citizens were younger than 15 years of age, and 47 565 were younger than 20 years of age. From 1994 to 1999, the population was stable, with an average annual migration rate of less than 4.8%. The annual family income,

Universal screening for biliary atresia using an infant stool color card in Taiwan

39 963 (in U.S. dollars), was the third highest among the 12 districts in Taipei (13). From 1985 through 1990, the HBsAg carrier rate among pregnant women14% (14)was similar to the national average (3, 4). The 1916 participants in our 1999 study consisted of 1) 157 children younger than 3 years of age enrolled from the Well-Baby Clinic of the National Taiwan University Hospital Department of Pediatrics and from two day care centers; 2) 232 children 3 to 6 years of age recruited from two kindergarten classes; 3) 763 children 7 to 12 years of age enrolled from one public elementary school; 4) 205 children and adolescents 12 to 15 years of age enrolled from one public junior high school; 5) 219 adolescents 15 to 18 years of age enrolled from one high school; and 6) 340 first-year undergraduate students at the National Taiwan University, 19 to 20 years of age. We recruited the child and adolescent participants through poster advertisements and by invitation from the health staff of the Department of Pediatrics, National Taiwan University Hospital. The university student participants and the parents of enrolled children gave written, informed consent and provided the vaccination history of the participant, according to his or her personal health booklet. (The booklet, which is used to record a persons vaccination history, is provided to the parents of all newborns by the Health Bureau of City Hall.) Serologic and Statistical Analyses We analyzed serum samples for HBsAg, HBsAg antibody (anti-HBs), and hepatitis B core antibody (anti-HBc) by using enzyme immunoassay (Abbott Laboratories, North Chicago, Illinois). We examined between-group differences in frequency by using the chi-square test with Yates correction or the Fisher exact test, where appropriate. A P value less than 0.05 was considered significant. Data analyses were performed by using GraphPad Prism, version 3.00 (GraphPad Software, Inc., San Diego, California). Role of the Funding Source The funding source had no role in the collection, analysis, and interpretation of the data or in the decision to submit the paper for publication. Results In 1999, the vaccination coverage rate was greater than 90% among children younger than 8 years of age and 80% to 86% among children 8 to 15 years of age (Table). These figures might be underestimates because some of the participants, particularly in the older age group, had missing vaccination cards; in other cases (for 23 of the 541 children younger than 8 years of age and 63 of the 766 participants 8 to 15 years of age), the parents could not recall the vaccination history. Infants had a lower coverage rate than other age groups because some of them had not yet finished their vaccination schedule (Appendix Table). Table. Seroprevalence of Hepatitis B Surface Antigen and Its Antibody in Chung-Cheng District, Taipei City, Taiwan, in 1984, 1989, 1994, and 1999 The prevalence of HBsAg in children younger than 15 years of age, 0.7% (9 of 1357), was considerably lower than the rate of 7% (39 of 559) observed in participants older than 15 years of age, who were born before the universal vaccination program (P < 0.001). Of the 9 children who were born after the vaccination program was instituted and tested positive for HBsAg, only 1 had not received the scheduled vaccinations, and the mother of this child was also HBsAg positive. According to their vaccination cards, the 8 other participants had received at least three doses of the HBV vaccine, and the first dose had been given within 1 week of birth. Seven of these 8 participants had mothers who were HBsAg carriers, and the remaining participant was living with two grandparents who were HBsAg positive. All 9 participants tested positive for anti-HBc. Eight of these 9 HBsAg carriers had received the plasma-derived vaccine, and 1 had received the yeast-derived recombinant vaccine; however, type of vaccine did not affect the rate of HBsAg seropositivity (8 of 968 persons who received the plasma-derived vaccine were carriers vs. 1 of 389 who received the yeast-derived vaccine; P > 0.2, Fisher exact test). The overall prevalence of anti-HBs in persons younger than 15 years of age in 1999 was 75.8%. We observed the highest prevalence of anti-HBs in children younger than 5 years of age (Table). The longitudinal perspective of HBsAg carriers in cohorts 0 to 1 years of age is shown in the Figure. Figure. Longitudinal perspective of the proportion of hepatitis B surface antigen carriers among the cohorts of 0 to 1 year of age in 1984 (circles) and 1989 (squares) in Chung-Cheng District, Taipei City, Taiwan. Children in the 1984 0- to 1-year age cohort, who were born before universal vaccination in Taiwan, had a carrier rate of 5.1% in 1984, 3.9% in 1989 (at age 5 to 6 years), 4.7% in 1994 (at age 10 to 11 years), and 7.5% in 1999 (at age 15 to 16 years). These proportions are significantly higher than those observed over time in the 1989 0- to 1-year age cohort, who were born since the national vaccination program started, at the corresponding age points (from the survey years 1989, 1994, and 1999, respectively). The rate of anti-HBc seropositivity was 2.9% in persons younger than 15 years of age but was 20.6% in persons 15 years of age or older (P < 0.001). In contrast, the rate of anti-HBc seropositivity among children younger than 15 years of age was 26.2% in 1984 (6), 14.5% in 1989 (11), and 4.0% in 1994 (12). Discussion The prevalence of HBsAg among children younger than 15 years of age decreased from 9.8% to 0.7% in the 15 years since implementation of the universal vaccination program. A high coverage rate for HBV vaccination is crucial for decreasing the prevalence of HBV infection. We observed a vaccination rate of at least 80% among children younger than 15 years of age and as high as 97% among children 4 years of age or younger. A nationwide series of seroepidemiologic studies of three cohorts of children 6 years of age in 1989, 1991, and 1993 reported that the vaccination rates for HBV ( 3 doses of vaccine) were 27.8%, 60.7%, and 88.7%, respectively (9). The age of these three cohorts in 1999 correspond to the age groups of 15 to 18 years, 13 to 14 years, and 11 to 12 years in our study. The data from these three national cohort studies confirm that the vaccination rate in our sample is similar to the vac

Mother-to-infant transmission of hepatitis B virus infection: Significance of maternal viral load and strategies for intervention

Biliary atresia is the most common cause of death from liver disease in children. Although the Kasai operation before 60 days of age can significantly improve prognosis, delay in referral and surgery remains a formidable problem worldwide because of difficulties in differentiating it from benign prolonged neonatal jaundice. We established a universal screening system using an infant stool color card to promote the early diagnosis and treatment of biliary atresia. After a pilot regional study in 2002–2003, a national stool color screening system was established by integrating the infant stool color card into the child health booklet given to every neonate in Taiwan since 2004. Within 24 hours of the discovery of an abnormal stool color, this event is reported to the registry center. The annual incidence of biliary atresia per 10,000 live births in 2004 and 2005 was 1.85 (40/216,419) and 1.70 (35/205,854), respectively. The sensitivity of detecting biliary atresia using stool cards before 60 days of age was 72.5% in 2004, which improved to 97.1% in 2005. The national rate of the Kasai operation before 60 days of age increased from 60% in 2004 to 74.3% in 2005. The jaundice‐free rate (<2 mg/dL) at 3 months after the Kasai operation among infants with biliary atresia in 2004–2005 was 59.5% (44 of 74), significantly higher than the historical data of 37.0% in 1976–2000 before the stool card screening program (P = 0.002). Conclusion: Universal screening using the stool color cards can enhance earlier referral, which may ultimately lead to timely performance of the Kasai operation and better postoperative outcome in infants with biliary atresia. (HEPATOLOGY 2008.)

Lactobacillus casei rhamnosus Lcr35 in children with chronic constipation

BACKGROUND & AIMS Immunoprophylaxis reduces but does not completely eradicate hepatitis B virus (HBV) transmission. This prospective study aims at assessing the rate and risk factors of maternally transmitted HBV infection. METHODS We enrolled 303 mother-infant pairs with positive maternal hepatitis B surface antigen (HBsAg) under current immunization program. Maternal viral load was determined by a real-time PCR-based assay. The children were tested for HBsAg at 4-8 months and/or 1-3 years of age. Rates of HBV infection were estimated using a multivariate logistic regression model. RESULTS HBeAg-positive mothers (81/303, 26.7%) had higher viral loads than HBeAg-negative mothers (7.4 ± 1.9 vs. 2.7 ± 1.4 log10 copies/ml, p<0.0001). Ten children, born to HBeAg-positive mothers with high viral load (median, 8.4; range, 6.5-9.5 log₁₀ copies/ml), were chronically infected. After adjustment for maternal age, birth type, factors related to maternal-fetal hemorrhage, gestational age, infant gender, birth weight, timeliness of vaccination, and feeding practice, maternal viral load was significantly associated with risk of infection (adjusted odds ratio for each log₁₀ copy/ml increase, 3.49; 95% confidence interval (CI), 1.63-7.48; p=0.001). The predictive rates of infection at maternal viral load levels of 7, 8, and 9 log₁₀ copies/ml were 6.6% (95% CI, 0.5-12.6%; p=0.033), 14.6% (95% CI, 5.6-23.6%; p=0.001), and 27.7% (95% CI, 13.1-42.4%; p<0.001), respectively. CONCLUSIONS Additional strategies to further reduce transmission should be considered in mothers with a viral load above 7-8 log₁₀ copies/ml.

Screening for Biliary Atresia by Infant Stool Color Card in Taiwan

Background: The purpose of the present paper was to evaluate the efficacy of probiotics (Lactobacillus casei rhamnosus, Lcr35) for treating children with chronic constipation and to compare its effect with magnesium oxide (MgO) and placebo.

Long-term prognosis of patients with biliary atresia: a 25 year summary.

OBJECTIVE. We aimed to detect biliary atresia (BA) in early infancy to prevent additional liver damage because of the delay of referral and surgical treatment and to investigate the incidence rate of BA in Taiwan. METHODS. A pilot study to screen the stool color in infants for the early diagnosis of BA was undertaken from March 2002 to December 2003. We had designed an “infant stool color card” with 7 numbers of different color pictures and attached it to the child health booklet. Parents were then asked to observe their infants stool color by using this card. The medical staff would check the number that the parents chose according to their infants stool color at 1 month of age during the health checkup and then send the card back to the stool color card registry center. RESULTS. The average return rate was ∼65.2% (78184 infants). A total of 29 infants were diagnosed as having BA, and 26 were screened out by stool color card before 60 days of age. The sensitivity, specificity, and positive predictive value were 89.7%, 99.9%, and 28.6%, respectively. Seventeen (58.6%) infants with BA received a Kasai operation within 60-day age period. The estimated incidence of BA in screened newborns was 3.7 of 10000. CONCLUSIONS. The stool color card was a simple, efficient, and applicable mass screening method for early diagnosis and management of BA. The program can also help in estimating the incidence and creating a registry of these patients.

Pediatric fulminant hepatic failure in endemic areas of hepatitis B infection: 15 years after universal hepatitis B vaccination

Objective: The purpose of this study was to delineate the long-term prognosis of biliary atresia (BA) in Taiwan. Study Design: From 1976 to 2000, 185 children were diagnosed with BA, 22 underwent exploratory laparotomy without Kasai operation, and 163 underwent Kasai operation, of which 141 cases had long-term follow-up and formed the basis of this study. The outcome was analyzed. Results: Among the 141 BA children studied who underwent Kasai operation, 115 (81.6%) had recoloration of stools, and 86 (61.0%) became jaundice-free (bilirubin <20 μmol/L). The resolution of jaundice and the absence of repeated cholangitis contributed to better outcome. Five and 10 year survival rates with native liver were 35% and 31%, respectively. Liver transplantation was performed in 19 patients (all but 2 with a living-related donor), and 15 (79%) survived. Five and 10 year overall survival rates for BA patients were 41.9% and 40.2%, respectively. Conclusions: The study delineated the long-term outcome of BA in an Asian country other than Japan. Survival with native liver after a Kasai operation in Taiwan was similar to that in the American and European series. Limited donors for liver transplantation in the years of the study accounted for the poor overall prognosis of BA patients in this series.

Efficacy of maternal tenofovir disoproxil fumarate in interrupting mother-to-infant transmission of hepatitis B virus

To investigate the role of hepatitis B virus (HBV) infection in pediatric fulminant hepatic failure (FHF) after the launch of universal HBV vaccination, the authors analyzed the data from patients with FHF collected from a nationwide collaborative study group. Children aged 1 month to 15 years who were diagnosed with FHF (62 males and 33 females) between 1985–1999 were included. HBV infection (hepatitis B surface antigen [HBsAg] and/or immunoglobulin M hepatitis B core antibody [IgM anti‐HBc] seropositive) accounted for 46% (43 of 95 cases) of all the cases of FHF. The average annual incidence of FHF in the time period 1985–1999 was 0.053/100,000 in the group of patients ages 1–15 years and 1.29/100,000 in those patients age < 1 year. Approximately 61% (58 of 95 cases) of all FHF cases were infants. The percentage of HBV infection was found to be higher in infants (57%) compared with children ages 1–15 years (27%) (P = 0.004). The incidence rate ratio of those patients age < 1 year to those ages 1–15 years was 54.2 for HBV‐positive FHF and 15.2 for HBV‐negative FHF. Maternal HBsAg was found to be positive in 97% of the infants with HBV‐positive FHF, and hepatitis B e antigen (HBeAg) was found to be negative in 84% of these infants. Approximately 74% of all HBV‐positive FHF patients and 81% of the infantile HBV‐positive patients had been vaccinated. In conclusion, within the first 15 years of universal vaccination, HBV was found to rarely cause FHF in children age > 1 year but remained a significant cause of FHF in infants. HBV‐positive FHF was prone to develop in infants born to HBeAg‐negative, HBsAg‐carrier mothers; these infants had not received hepatitis B immunoglobulin according to the vaccination program in place. (HEPATOLOGY 2004;39:58–63.)

Expression of Hepatocyte Transporters and Nuclear Receptors in Children With Early and Late-Stage Biliary Atresia

The efficacy and safety of maternal tenofovir disoproxil fumarate (TDF) in reducing mother‐to‐infant hepatitis B virus (HBV) transmissions is not clearly understood. We conducted a prospective, multicenter trial and enrolled 118 hepatitis B surface antigen (HBsAg)– and hepatitis B e antigen–positive pregnant women with HBV DNA ≥7.5 log10 IU/mL. The mothers received no medication (control group, n = 56, HBV DNA 8.22 ± 0.39 log10 IU/mL) or TDF 300 mg daily (TDF group, n = 62, HBV DNA 8.18 ± 0.47 log10 IU/mL) from 30‐32 weeks of gestation until 1 month postpartum. Primary outcome was infant HBsAg at 6 months old. At delivery, the TDF group had lower maternal HBV DNA levels (4.29 ± 0.93 versus 8.10 ± 0.56 log10 IU/mL, P < 0.0001). Of the 121/123 newborns, the TDF group had lower rates of HBV DNA positivity at birth (6.15% versus 31.48%, P = 0.0003) and HBsAg positivity at 6 months old (1.54% versus 10.71%, P = 0.0481). Multivariate analysis revealed that the TDF group had lower risk (odds ratio = 0.10, P = 0.0434) and amniocentesis was associated with higher risk (odds ratio 6.82, P = 0.0220) of infant HBsAg positivity. The TDF group had less incidence of maternal alanine aminotransferase (ALT) levels above two times the upper limit of normal for ≥3 months (3.23% versus 14.29%, P = 0.0455), a lesser extent of postpartum elevations of ALT (P = 0.007), and a lower rate of ALT over five times the upper limit of normal (1.64% versus 14.29%, P = 0.0135) at 2 months postpartum. Maternal creatinine and creatinine kinase levels, rates of congenital anomaly, premature birth, and growth parameters in infants were comparable in both groups. At 12 months, one TDF‐group child newly developed HBsAg positivity, presumably due to postnatal infection and inefficient humoral responses to vaccines. Conclusions: Treatment with TDF for highly viremic mothers decreased infant HBV DNA at birth and infant HBsAg positivity at 6 months and ameliorated maternal ALT elevations. (Hepatology 2015;62:375–386

No Increase in Prevalence of Hepatitis B Surface Antigen Mutant in a Population of Children and Adolescents Who Were Fully Covered by Universal Infant Immunization

To investigate how the liver adapts to chronic obstructive cholestasis, liver samples from infants with early- and late-stage cholestasis were analyzed for changes in the levels of hepatocyte transporters and nuclear receptors. At early-stage cholestasis, most canalicular transporters and sinusoidal uptake transporters were downregulated, including bile salt export pump (BSEP, ABCB11), multidrug resistant protein 3 (MDR3, ABCB4), multidrug-resistant associated protein 2 (MRP2, ABCC2), sodium-dependent taurocholate cotransporting polypeptide (NTCP, SLC10A1), organic anion transporter (OATP, SLCO1A2), and nuclear receptor farnesoid X receptor (FXR, NR1H4). At late-stage cholestasis, FXR-BSEP levels returned to normal, MDR3 and MDR1 (ABCB1) were upregulated, and MRP-2 was downregulated. In addition, alternative sinusoidal efflux transporters, organic solute transporter alpha/beta (OSTα/β) and MRP4 were upregulated, and pregnane X receptor (PXR, NR1I2) levels decreased. Cytochrome enzyme P450 7A1 was markedly downregulated at both early and late-stage cholestasis. An analysis of the long-term prognosis of 18 patients revealed lower PXR and constitutive androstane receptor (CAR, NR1I3) levels in the poor prognosis group. In conclusion, at long-term cholestasis, hepatocyte bile efflux was through sinusoidal and canalicular transporters, with FXR-BSEP levels maintained and PXR downregulated. Low PXR and CAR levels were associated with poor prognosis.