Neonatal infections - Infection with hepatitis B

Hepatitis B gives the most severe form of neonatal hepatitis.
Vertical transmission during childbirth is 1%, skin and mucous membranes from exposure to blood infected newborn.Transplacental streaming occurs less frequently, at a rate of 5-15% if HBeAg positive mothers. Horizontal transmission occurs at a rate of 5%, parenteral transmission in 38%, 30% of sexual transmission and transmission cases not referred to in 26-30% of cases.
Risk factors for transmission of hepatitis B virus (HBV) in newborns:- If there is maternal HBV infection in quarter 3 of pregnancy, the rate of infection in newborns is 80-90%;- If there is maternal HBV infection in quarter 1 and 2 of pregnancy, the risk of infection in newborns is 10%;- Surrogate mother is HBsAg and HBeAg chronic risk increases to 70-80%;- Mother carrying HBeAg, the risk of chronic carriers is low and the rate of infection in newborns is 30%;- Mother carrying AcHBe HBeAg and the risk of transmission is very low risk of infection and healthy carrier is 10-20%;- HBs antibodies from the mother bearing the risk of transmission to the newborn is 0.
Clinical signs:
Most infections are subclinical or HBV infection is mild and asymptomatic anicterica: moderate increase in transaminases, mild hepatomegaly, presence of HBsAg.Neonates of mothers with HBV in the last trimester of pregnancy may be acute hepatitis or anicterigena icterigena: marked increase in transaminases, malaise, hepatomegaly, or may be fulminant hepatitis.Most infants become chronic carriers of HBsAg and HBeAg if mothers present and then one third of them develop chronic hepatitis, progressive, eventually leading to cirrhosis or hepatocellular carcinoma.
Prophylaxis in the newborn:
Newborns of positive mameAgHBs must wash to remove secretions from infected early and gastric aspiration if necessary should be done gently to avoid damage to the lining and allow penetration of HBV in the blood.Birth by cesarean section was supported by some authors to reduce the risk of transmission of HBV but other authors do not recommend this.Hepatitis B vaccination of all newborns regardless of maternal serology, the first dose at birth and these doses at 2 and 6 months.Vaccination is recommended for all infants regardless of their antigenic status.
Breastfeeding should be allowed for infants who started Immunoprophylaxis.Newborns of HBsAg-positive mothers receive immune globulin and vaccine HBsAg HBs. Immunoglobulin is effective if done soon after birth as well as in the first 12 hours at a dose of 0, 5 ml intra-muscular. The remaining doses will be administered every 1-2 weeks and 6 months.