DEPARTMENT OF GENITO-URINARY MEDICINE HEPATITIS B

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1 DEPARTMENT OF GENITO-URINARY MEDICINE MAIN TRANSMISSION ROUTES HEPATITIS B Sexual transmission Occurs in unvaccinated/non immune men who have sex with men and correlates with multiple partners, unprotected anal sex and also oro-anal sex ( rimming ) Transmission also occurs after heterosexual contact e.g 18% infection rates for regular partners of patients with acute hepatitis B Sex workers are also at a higher risk Parental (Blood, Blood products, injecting drug users sharing needles and syringes, needle stick, acupuncture and tattoos) Vertical transmission (infected mother to infant) SCREENING AND PRIMARY PREVENTION OF HEPATITIS B The following populations should be screened for hepatitis B immunity and offered vaccination if no previous exposure and on-going risk. Men who have sex with men Male / Female sex workers Injecting drug users People who have been sexually assaulted Partners of infected clients HIV positive patients Men who have sexual partners, from South - East Asia (China and Thailand ) Men and women who have multiple sexual partners In exceptional circumstances healthcare and other staff (e.g. Police) that may be at risk of needle stick injuries can be screened in GUM however this should usually be done through the appropriate Occupational Health Department HBcAb (Hepatitis B Core Antibody) Initial screening test in someone who is unvaccinated and is of unknown infection status If found to be HBcAb positive the lab will go on to undertake further carrier status by testing for HBsAg and HBsAbs. If HBcAb negative please recall patient for vaccination if in a high risk group

2 VACCINATION SCHEDULE: The current schedule used in the Department is 0, 1, 6 months Sexual assault patients should be offered an accelerated schedule of 0, 1, 2, 12 months Separate vaccines for Hep A and Hep B are also available where there is a clear history of prior infection Routine vaccination for gay / bisexual men attending GUM is by Twinrix vaccine, unless prior infection or previous vaccination with either Hep A or Hep B has occurred. The current policy in this clinic is not to undertake routine Hep A screening prior to vaccination. Measure the titres of HBsAb s in those who have been vaccinated at least 8 weeks after third dose has been administered. MISSED VACCINE DOSES: If more than 4 weeks since first vaccine, the patient should be contacted and arrangements made for the course to be completed. The full immunisation schedule should take place within 12 months, as recommended in The Green Book. If first 2 doses given, the outstanding final dose can be given up to 12 months later without the need to restart another three dose course. Table 1 SUMMARY OF HEPATITIS TESTS SITUATION TEST INTERPRETATION New Client with history of Hep B vaccination Check HBsAb s >/= 100 IU/L Responder to hepatitis B vaccination. No further antibody checks required however booster dose is required after 5 years For results below 100 IU/L seetable 2 2

3 SITUATION TEST INTERPRETATION New Client with Hep B risk HBcAb Negative: No infection Offer vaccination Positive HBcAb Positive HBcAb HBsAg neg HBsAg+ Positive: Further tests undertaken by lab Naturally immune provided that the HBsAb s are also positive at any titre If positive > 6/12 then chronic hepatitis B carrier requires HBeAg and HBeAb investigations before referral to gastroenterologist. Chronic Hep B Chronic Hep B HBsAg + > 6/12 HBeAg+ and HBeAb neg HBeAg neg and HBeAb+ High-infectivity carrier Low infectivity carrier 3

4 Table 2 AFTER STANDARD PRIMARY COURSE COMPLETED (3 dose schedule) CHECK TITRES 8 WEEKS AFTER 3 RD DOSE. Depending on results, please follow recommendations as outlined below. TITRE (IU / L) < 10 IU/L >10 <100 IU/L RECOMMENDATION Failure to respond to hepatitis vaccination ACTION Repeat with 3 double dose vaccines, check titres after 8 weeks Up to 3 separate booster doses can be given Check titres 8 weeks after each individual booster and discuss results with consultant >/= 100 IU/L Responder to hepatitis B vaccination. No further antibody checks required however booster dose is required after 5 years Table 3 AFTER ADDITIONAL DOSES <10 IU/L Non responder to hepatitis B vaccination. This person remains susceptible to HBV infection and may require prophylactic treatment in the event of a significant needlestick or similar injury. If double dose x 3 given, no response - STOP Check HBcAb if not already done. >/= 10 IU/L Responder to hepatitis B vaccination depending on the level discuss with Consultant No further antibody checks required and no further boosting unless for prophylaxis after significant exposure. 4

5 MANAGEMENT OF ACUTE HEPATITIS B 1. Confirm diagnosis by HBsAg and IgM core antibody 2. Bloods for LFT s, U/E s, prothrombin time, STS and HIV, Hep A IgM and Hepatitis C antibody 3. Refer to health advisor for partner notification and general advice, Patients should be advised to avoid unprotected sexual intercourse, including oro-anal and oro-genital contact until they have become noninfectious or their partners have been successfully vaccinated. 4. Patients should also be given a detailed explanation of their condition with particular emphasis on the long term implications for the health of themselves and their partner(s). 5. Routes of transmission of infection should be discussed and patients should be advised not to donate blood, semen, or share toothbrushes, razors or scissors. 6. Urgent referral to Gastroenterologist NB. Hepatitis B is a notifiable condition. The patient needs to be informed about the need for referral to the Health Protection Agency Please obtain written consent from the patient before a referral is made and document this in the notes. Contact Health Protection Agency on Tel PARTNER NOTIFICATION Should include any sexual contacts (penetrative vaginal, anal, oro-anal sex) or needle sharing partners during the period in which the index case is thought to have been infectious. The infectious period is for two weeks before the onset of jaundice until the patient becomes surface antigen negative. In cases of chronic infection trace contacts as far back as any episode of jaundice or to the time when the infection is thought to have been acquired although this may be impractical for periods longer than 2 or 3 years 5

6 MANAGEMENT OF CHRONIC HEPATITIS B INFECTION Bloods must be taken for LFT s, FBC, U/E s, Glucose, egfr, INR, Hepatitis C Abs, auto immune antibodies, ANCA, HIV, Syphilis, Hep B DNA levels. Check with the patient for consent to inform GP or other services and document this in the notes. A request card to organise an ultra sound scan should be given to the patient, with advice to book the appointment at the x-ray department directly. Patients must be referred to a Gastroenterologist for continuing care and follow up. Patients to be vaccinated against Hepatitis A Hepatitis D (Delta Virus Infection) This is an incomplete RNA virus that requires the hepatitis B virus outer coat. It is only found in patients with hepatitis B. It is largely an infection of IVDA s and their sexual partners but also in female sex workers, and sporadically in other groups. Suspect HDV in hepatitis B particularly if the acute hepatitis is severe, if chronic hepatitis B carriers get a further episode of acute hepatitis or, if the liver disease in chronic HBV is rapidly progressive. Response to anti-viral therapy is poor. Diagnosis is confirmed by a positive anti-hdv antibody or HDV-RNA test. HIV positive patients HIV positive patients respond less well to the vaccine, and the response rate varies with the CD4 count with best response (c.80%) at >500 cells/ul and least response (c.25%) with counts <200 cells/ul. Protective antibodies are lost more quickly. References Department of Health (2006) p 79 Immunisation against Infectious Disease: The Green Book London, TSO. United Kingdom National Guideline on the management of the Viral Hepatides A, B and C British HIV Association guidelines for the management of coinfection with HIV-1 and hepatitis B or C virus