Epidemiology and clinical features of childhood chronic hepatitis B infection diagnosed in England.

BACKGROUND: This study aimed to estimate the prevalence of childhood chronic hepatitis B (CHB) infection diagnosed in England using capture-recapture analysis of 2 independent data sources and to describe the clinical and epidemiological characteristics, management, complications and outcome of children with CHB. METHODS: Pediatric specialists were contacted to report all CHB cases in children aged <16 years and complete a standardized questionnaire. Capture-recapture analysis of cases diagnosed during 2001-2009 using 2 independent data sources was performed to estimate the prevalence of childhood CHB. RESULTS: Capture-recapture analysis estimated 448 diagnosed CHB cases (prevalence, 4.6/100,000) in England, of whom only 44% had been referred for specialist follow up. Clinical information for 325 cases under specialist care revealed that half the cases (n = 164, 50%) had been born overseas, mainly Sub-Saharan Africa and Eastern Europe, whereas half the UK-born children were either Pakistani (25%) or Chinese (25%). Most children (n = 216, 66%) were asymptomatic, with only 60 (18.5%) ever receiving any antiviral therapy, although 2 developed cirrhosis in childhood and 1 hepatocellular carcinoma. Horizontal transmission among UK-born children was identified in only 3 children born since 2001, when universal antenatal hepatitis B virus screening was introduced. Most children born to antenatally diagnosed hepatitis B virus-positive mothers (49/51, 96%) had received at least 1 hepatitis B vaccine dose after birth. CONCLUSIONS: In England, the prevalence of diagnosed childhood CHB is low, although the potential number of undiagnosed cases is difficult to estimate. Further efforts are required to strengthen the current antenatal screening program and newly diagnosed cases should be referred for specialist follow up.

Does genotype predict response to treatment in children infected with hepatitis B perinatally?

HBV genotype may correlate with outcome and treatment response. Genotype has been compared with treatment response in children infected perinatally with hepatitis B following treatment with oral antiviral drugs (lamivudine or adefovir) or interferon (IFN) alone and with prednisolone priming (Pred/IFN). All children who took part in clinical trials in this unit since 1990 were included. Hepatitis B genotypes were determined by direct sequencing or using a commercial line probe assay (InnoLipa). Sixty-five children were included; 20 were treated with IFN; 19 with Pred/IFN; 22 with lamivudine and 7 with adefovir, some took part in more than one treatment study. 63 out of 65 children were clearly typed into single genotypes; 16, 7, 3, and 37 typing as A, B, C, and D respectively. The majority of South-Asian children had genotype D and European and Afro-Caribbean children were more likely to have genotype A. Treatment response (seroconversion from HBeAg to Anti-HBe) was better in children with genotypes A [n = 16] and D [n = 37] (55.5% and 48.7%), compared to those with B [n = 7] and C [n = 3] (12.5% and 0%) for all treatments. The response to interferon alone was better in children with genotype A compared to D (50% and 36%), but prednisolone priming improved the response so that there was no difference between genotypes A and D (66.7% and 70%). Assessment of genotype in children pre-treatment may provide a guide to potential response. The response to treatment by genotype should be evaluated in future clinical trials in children.

Discordant outcome of perinatal transmission of hepatitis C in twin pregnancies.

BACKGROUND: Mother to infant transmission of hepatitis C virus (HCV) is dependent on significant HCV viraemia being present in the mother. As yet there are no appropriate interventions to prevent perinatal transmission. The investigation of twin pregnancies where only one twin is infected may reveal further information relating to transmission and specific risks. Evaluation of these risks could affect decisions about the management of the deliveries of these mothers while more appropriate interventions are evaluated. STUDY DESIGN: The laboratory database was searched for all twins referred for testing at the Children's Hospital Liver Unit. The mothers and health care providers were contacted to gain more information about the pregnancies and deliveries of all of the twins. RESULTS: Four sets of twins had been investigated for HCV. In all cases only one twin had been infected. In three out of four cases the second twin had become infected. All of the twins were girls and the larger twin in each pair became infected. Premature rupture of membranes was associated with transmission in the only case in which the first-born became infected. There was no invasive foetal monitoring or episiotomy in any of the deliveries SUMMARY AND CONCLUSIONS: Transmission of HCV is more likely to affect the second twin, perhaps because placental separation during the delivery of the second twin exposes the infant to infection. Until effective interventions such as vaccination of newborns or antiviral treatment of mothers are evaluated, elective caesarean section could be recommended for HCV twin pregnancies in order to avoid premature membrane rupture and infection of the second twin.

Long-term follow-up of hepatitis B carrier children treated with interferon and prednisolone.

The long-term outcome of treatment with Interferon Alpha 2B with and without Prednisolone priming in children infected perinatally with hepatitis B was reviewed. The group studied included 48 children (aged 2-16 years), who were HBe antigen and hepatitis B DNA positive between 1991 and 1993. Twenty children were randomized to a therapeutic trial at that time, and received Prednisolone in reducing doses for 6 weeks and Interferon for 16 weeks while 22 children were monitored without treatment for 12 months. Fourteen of the untreated group and 6 additional children later received treatment with Interferon alone (n = 20). Eight children for whom treatment was declined were followed long term. Median follow-up was 7.5 years (range 1.5-10.6). There was no significant effect of Interferon therapy on seroconversion with or without Prednisolone at 12 months post-treatment compared to untreated children. On longer term follow-up, the 5-year HBeAg to anti-HBe seroconversion percentages, estimated from Kaplan-Meier curves, were 54% for Prednisolone plus Interferon, 22% for Interferon alone, and 12% for untreated children. The median time to seroconversion was 3.9 years (range 0.4-8.2) and was shortest in those treated with Prednisolone plus Interferon. Children who had elevated hepatic transaminase enzymes prior to treatment or during Prednisolone priming had a better response. In contrast to many European studies, no child cleared HBsAg and produced anti-HBs. Treatment with Prednisolone priming and Interferon, improved both the time and rate of seroconversion compared to no treatment or Interferon alone, suggesting that this combination of drugs might have an immunomodulatory effect.

Long-term persistence of immunity to hepatitis B after vaccination during infancy in a country where endemicity is low.

BACKGROUND: The long-term response to hepatitis B vaccination during infancy has not been fully evaluated in countries where endemicity is low. METHODS: The present study was a serological investigation of immunity to hepatitis B during adolescence. In a cohort of children who were born to hepatitis B virus carrier mothers and who were vaccinated during infancy, evidence of past or current infection and the response to a single booster dose of vaccine were analyzed. Sixty-four children whose antibody levels were measured after immunization (group 1) and 52 younger siblings who did not undergo postvaccination antibody tests (group 2) were studied. RESULTS: One child in each group showed evidence of natural infection. In group 1, 32 children (50%) had undetectable antibody to hepatitis B surface antigen (anti-HBs), and only 8 (13%) had levels >100 mIU/mL. After a booster dose of vaccine, only 7 (11%) still had undetectable anti-HBs, 3 (5%) showed a primary response, and 50 (78%) had levels >100 mIU/mL. Five of the 7 vaccine nonresponders and all of the primary responders had also received hepatitis B-specific immunoglobulin (HBIG) at birth. The children in group 2 showed a similar response to the vaccine, but with slightly higher levels of anti-HBs. CONCLUSIONS: Most children vaccinated at birth retain immunological memory to hepatitis B vaccine for 15 years, but those who did not were more likely to have received HBIG at birth, suggesting that passive antibody may interfere with the induction of immunological memory.