Children’s hepatitis B prevention and treatment, just read this one

Only for medical professionals to read for reference.
Children's hepatitis B treatment should be carried out early.
From the discovery of hepatitis B (hereinafter referred to as hepatitis B) virus in 1967, the development of hepatitis B vaccine in 1969, to the continuous emergence of hepatitis B treatment drugs, hepatitis B prevention and control work has achieved remarkable results
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At present, the prevention of hepatitis B has achieved definite results.
What are the key points that need to be paid attention to in the prevention and treatment of hepatitis B in children? At the 26th National Pediatric Academic Conference of the Chinese Medical Association, Professor Wang Jianshe from the Pediatric Hospital of Fudan University gave a wonderful report on the prevention and treatment of hepatitis B in children
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 Mother-to-child transmission has become the main cause of hepatitis B transmission in China.
The transmission route of hepatitis B presents new characteristics
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Through pre-transfusion screening and the use of vaccines, the horizontal transmission of hepatitis B is almost completely blocked
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Almost all children infected with chronic hepatitis B virus (HBV) are caused by mother-to-child transmission
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Mother-to-child transmission has become the main cause of hepatitis B transmission in China
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So how to diagnose mother-to-child transmission of HBV? First of all, pay attention to the timing of diagnosis
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Positive blood hepatitis B surface antigen (HBsAg) and (or) HBV DNA at 7-12 months of age can be diagnosed as mother-to-child transmission.
Note that it is not diagnosed at birth
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This is because the positive rate of HBsAg and (or) HBV DNA in venous blood or cord blood within 24 hours after birth is significantly higher than that of venous blood test results at the age of 6 months, 7 months or 12 months, and HBsAg and (or) at birth A positive HBV DNA does not mean that mother-to-child transmission has occurred.
It may be a false positive caused by maternal blood contamination, or temporary viremia in the newborn caused by placental separation during delivery [1]
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At the same time, when the baby is tested for 7-12 months of age, the baby has completed the hepatitis B vaccination, and the effect of the hepatitis B vaccine can be tested at the same time
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Second, note that E antigen, E antibody, and core antibody cannot be used as the basis for diagnosis of mother-to-child transmission
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HBsAg and HBV DNA should be tested for diagnosis of mother-to-child transmission .

The E antigen, E antibody, and core antibody in the mother's body can be passed to the newborn through the placenta.
The E antigen disappears when the baby is 4 months old, the E antibody disappears within 1 year of age, and the core antibody disappears within 2 years of age, so E antigen disappears within 2 years of age.
Antigens, E antibodies and core antibodies cannot be used as indicators of mother-to-child transmission
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Interruption of mother-to-child transmission of hepatitis B is the main route of hepatitis B transmission, and the interruption of mother-to-child transmission is very important
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If preventive measures are not taken, 90% of E antigen-positive mothers will have mother-to-child transmission; E antigen-negative mothers will have 30%-50% of mother-to-child transmission
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With the widespread vaccination of hepatitis B vaccine, more than 95% of mother-to-child transmission has been blocked
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The current strategy for blocking mother-to-child transmission in China is that newborns of HBsAg-positive mothers should: (1) complete the combined immunization of hepatitis B vaccine and 100 IU hepatitis B immunoglobulin as soon as possible within 12 hours after birth; (2) Vaccine the second and third shots of hepatitis B vaccine at the age of 1 and 6 months [1]
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In addition to the above two post-natal measures, another measure to block mother-to-child transmission of hepatitis B is to reduce the load of HBV by taking antiviral drugs before the baby is born, thereby reducing the risk of mother-to-child transmission
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The World Health Organization recommends that mothers with hepatitis B start to take tenofovir 300 mg at least until the baby is born[2]
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The "Guidelines for the Prevention and Control of Mother-to-Child Transmission of Hepatitis B Virus in China (2019 Edition)" recommends [1] to block mother-to-child transmission to the greatest extent: (1) When HBV DNA>2×105 IU/mL, oral antiviral drugs during pregnancy Block; (2) When 2×104 IU/mL≤HBV DNA≤2×105 IU/m, there is still a certain risk of mother-to-child transmission, especially for those with a family history of HBV infection and a history of one-child infection.
Fully communicate with patients, weigh the pros and cons, and decide whether to intervene with oral antiviral drugs; (3) For pregnant women with severe liver fibrosis and cirrhosis, antiviral therapy should be given regardless of the level of alanine aminotransferase (ALT)
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The timing of antiviral treatment during pregnancy is also very important.
According to the "Consensus on the Clinical Management of Women of Childbearing Age Infected with Hepatitis B Virus", it is recommended that antiviral drugs start to block mother-to-child transmission from 24 to 28 weeks of pregnancy [3]
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Intervention before 28 weeks of gestation compared with interventions at 28 weeks and beyond, the risk of transmission of the former was significantly reduced; and there was no increase in the incidence of adverse events in pregnant women and infants
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Another question that ensues is whether HBsAg-positive mothers can breastfeed? The answer is to be able to breastfeed, but there is a prerequisite
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In 2019, the "Guidelines for Prevention and Treatment of Chronic Hepatitis B" pointed out[4] that newborns can be breast-fed by HBsAg-positive mothers after being injected with HBIG and hepatitis B vaccine within 12 hours of birth
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 Three children's hepatitis B treatment targets and treatment drugs There are differences between children's hepatitis B treatment targets and adult hepatitis B treatment targets
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The treatment targets of adult hepatitis B patients are determined according to the patient's immune stage
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But the concept of immunization staging is not suitable for children
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For children with hepatitis B, it is recommended to use the phenotypic characteristics of chronic HBV infection [5] to classify and determine the treatment object: ▎Immune activity status: hepatitis B E antigen (HBeAg) +/-, elevated transaminase, HBV DNA>log104 IU /ml
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▎Immune tolerance status: HBeAg +, normal transaminase, HBV DNA>log104 IU/ml
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▎Inactive carriers: HBeAg +/-, normal transaminase, HBV DNA≤log104 IU/ml
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▎Unfinished: Not in the above three states
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For children with hepatitis B, the immune activity status should be treated
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The currently approved drugs for the treatment of hepatitis B in children include interferon, lamivudine, entecavir, adefovir and tenofovir.
It should be noted that each drug is adapted to different treatment ages and should be distinguished.
See Table 1
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Table 1 Approved drugs for the treatment of hepatitis B in children.
It should be noted that the treatment of hepatitis B in children should be carried out early.
For immunoactive children with chronic HBV infection, the earlier hepatitis B treatment, the better the effect
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Previous studies have suggested that as age increases, the percentage of surface antigens removed is lower
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Young chronic hepatitis B cannot be classified as immune tolerance, and young patients with chronic hepatitis B need antiviral therapy more than previously thought
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For the treatment of immunologically tolerant children with chronic HBV infection, it is still necessary to accumulate more clinical evidence
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In summary, please keep these points in mind about the prevention and treatment of hepatitis B in children: Hepatitis B vaccination is the most important measure for hepatitis B prevention.
At present, the main route of hepatitis B transmission is mother-to-child transmission
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Diagnosing mother-to-child transmission of hepatitis B requires selection of the correct test indicators at the right time for confirmation
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Interrupting mother-to-child transmission of hepatitis B, including antiviral treatment for pregnant women and interdiction measures for newborns after delivery
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Children with chronic HBV infection with active immunity, the earlier the treatment, the better
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Reference materials: [1] Chinese Medical Association Infectious Diseases Branch, GRADE China Center.
Guidelines for the prevention and treatment of mother-to-child transmission of hepatitis B virus in China (2019 edition)[J].
Chinese Journal of Infectious Diseases,2019,37(7):388- 396.
[2] FunkAL, Lu Y, Yoshida K, et al.
Efficacy and safety of antiviral prophylaxis during pregnancy to prevent mother-to-child transmission of hepatitis B virus: asystematic review and meta-analysis.
Lancet Infect Dis.
2021;21 (1):70-84.
[3] Xiaoguang Dou.
Consensus on the clinical management of women of childbearing age infected with hepatitis B virus[J].
Adolescent Health,2019,(2):38-42.
[4] Chinese Medical Association Infectious Diseases Branch, Chinese Medical Association Hepatology Branch.
Guidelines for Prevention and Treatment of Chronic Hepatitis B (2019 Edition)[J].
Journal of Practical Hepatology,2020,23(1):Post 9-Post 32.
[5] NicastroE, Norsa L , Di Giorgio A, Indolfi G, D'Antiga L.
Breakthroughs and challenges in the management of pediatric viral hepatitis.
World J Gastroenterol.
2021;27(20):2474-2494.