Blood-Borne Virus Educational Resource Pack
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NHS Lanarkshire Blood-borne virus educational resource pack Dr Nicholas Kennedy Consultant ID Physician and Clinical Lead, BBV MCN Dr Claire McGoldrick Consultant ID Physician Dr Iain Hathorn Clinical Director in Primary Care NHS Lanarkshire Blood-borne virus educational resource pack Dr Nicholas Kennedy Consultant ID Physician and Clinical Lead, BBV MCN Dr Claire McGoldrick Consultant ID Physician Dr Iain Hathorn Clinical Director in Primary Care Publication date: July 2011 Review date: July 2012 Edition No: 02 Dr Nicholas Kennedy Consultant Physician in Infectious Diseases Monklands District General Hospital Monkscourt Avenue Airdrie ML6 0JS Dr Claire McGoldrick Consultant Physician in Infectious Diseases Monklands District General Hospital Monkscourt Avenue Airdrie ML6 0JS Dr Iain Hathorn Clinical Director in Primary Care Red Deer Centre Alberta Avenue East Kilbride G75 8NH Designed and printed by www.publishingbureau.co.uk Acknowledgments The authors would like to thank colleagues who made many helpful comments and sug- gestions on the draft manuscript. In particular, we would like to acknowledge the major contribution made by Kathleen Macarthur, BBV Pharmacist. With her usual attention to detail, Kathleen spotted and corrected a number of errors that her lackadaisical medical colleagues had made, as well as suggesting several important additions. Contents 1. Introduction 1.1 Introduction ................................................................................4 2. Core information 2.1 Hepatitis B (HBV) ...........................................................................5 2.2 Hepatitis C (HCV) ..........................................................................8 2.3 Human Immunodeficiency Virus (HIV) ..................................................11 2.4 Blood-borne viruses: who should be tested for what? .................................15 3. Additional reference material 3A General information ......................................................................16 3A1 Worldwide distribution of blood-borne viruses ..................................16 3B Hepatitis B (HBV) ..........................................................................17 3B1 Interpretation of hepatitis B serological test results ..............................17 3B2 Guidelines for hepatitis B virus (HBV) vaccination in primary care .............18 3B3 Suggested primary pre-exposure HBV (± HAV) vaccination schedules and products ............................................................20 3C Hepatitis C (HCV) .........................................................................21 3C1 Algorithm for Dry Blood Spot (DBS) testing for HCV in outreach settings ....21 3C2 Non-invasive assessment of liver stiffness by transient elastography (Fibroscan) ................................................22 3C3 Predictors of treatment success for chronic HCV infection ......................22 3C4 Planned HCV treatment durations at start of treatment ........................23 3C5 Which pegylated interferon products are available?. 23 3C6 Common side-effects of therapy with pegylated interferon and ribavirin .....23 3C7 Individualised HCV treatment based on virological response during early therapy ................................................................24 3D HIV. .25 3D1 Clinical indicator conditions where HIV testing should be offered .............25 3D2 Anti-retroviral drug classes, individual drugs and combination tablets ........27 3D3 Examples of important drug interactions with NNRTIs and PIs .................29 3D4 Major adverse effects of HIV drugs ................................................30 4. Web links 4.1 Relevant web links ........................................................................34 5. Glossary 5.1 Glossary. .35 4 1.1 Introduction This educational resource on blood-borne virus (BBV) infections was originally developed as part of a resource pack for general practitioners in Lanarkshire, who were offered a Locally Enhanced Service (LES) to help increase hepatitis C (HCV) testing in primary care as one of a number of local initiatives introduced under the Hepatitis C Action Plan for Scotland. The original document, published in April 2010, contained a whole section relating specifi- cally to administrative aspects of the implementation of the LES. There was no section on HIV, as this was covered by a booklet on ‘HIV in Primary Care’ that was distributed to all GP practices who participated in the LES. Several readers suggested that the content of the original document could serve as the basis for a more generic educational pack on BBV infection that could be useful for readers from a variety of backgrounds, including GPs, hospital consultants, junior doctors, nursing staff, midwives and others (not necessarily from NHS backgrounds). The original document has therefore now been revised, with the removal of the administrative section relating to the LES, the addition of a section on HIV and the inclusion of more reference material relating to HCV. The original format of the document, which contained a relatively brief ‘core information’ section along with supplementary material within an ‘additional refer- ence material section’, has been retained. Broadening the intended target audience for this document does introduce some additional difficulties. Readers from different backgrounds will differ in their educational needs and areas of interest. Whilst acknowledging this, we have kept fairly closely to the format of the first version of the document – with a focus primarily on the clinical aspects of BBV infection and on BBV testing. However, web-links are provided where additional information can be obtained. We are also aware that the terminology used in this document is fairly technical and may at times be confusing for many who do not come from a medical background. We have tried to help as far as possible by now providing a glossary that covers the technical terminology used in the ‘core information’ section at least. We hope that you find the information provided in this document interesting. More impor- tantly, we hope that this information convinces you that HBV, HCV and HIV are infections that are now all eminently treatable – and indeed potentially curable in the case of HCV and some cases of HBV. Unfortunately, like many other medical conditions, late diagnoses are associated with adverse health outcomes, impaired treatment response and unneces- sary deaths. So we urgently need your help, whatever setting you work in, as we all strive to reduce undiagnosed BBV infection and late clinical presentations in Lanarkshire. Whilst the treatment of BBV infection is still a fairly specialised area, testing for BBV infection is not: all doctors, nurses and midwives should be able to obtain informed consent for a BBV test in the same way that they currently do for any other medical investigation – and should 1. Introduction feel empowered to do so. 5 2.1 Hepatitis B (HBV) What is it? ◾ DNA virus. At least 10 genotypes (A–J) How is it transmitted? ◾ mother-to-child transmission (commonest source on global basis, but uncommon in UK) ◾ blood-borne virus route – eg shared injecting equipment ◾ sexual transmission – much more readily transmitted sexually than HCV What is the incubation period? ◾ 6 weeks to 6 months (average ~ 120 days) Who is at risk? (See also The Green Book and section 2.4 ‘Who should be tested for what?’) ◾ infants born to HBV infected mothers (most commonly seen in SE Asian individuals) ◾ injecting drug users ◾ haemodialysis patients ◾ sexual partners of infected people ◾ men who have sex with men (MSM) ◾ travellers to countries with high or intermediate prevalence ◾ sexually active people with multiple partners (eg commercial sex workers) ◾ individuals in residential accommodation for those with learning difficulties ◾ household contacts of people with HBV infection ◾ healthcare workers and others at occupational risk How can it be prevented? ◾ a very effective vaccine is available ◾ harm reduction interventions for IDUs (clean needles/syringes/paraphernalia & substitute prescribing) are important ◾ condoms What are the symptoms and signs? ◾ acute infection: usually none if mother-to-child infection acute hepatitis ± jaundice may occur in adolescents & adults – occasionally fulminant hepatitis 2. Core Information ◾ chronic infection: usually none, unless advanced liver disease What are the potential complications associated with untreated infection? ◾ chronic (ie long-term) infection occurs in 90% of those who are infected as infants, but only ~ 5% of those infected as adults ◾ chronic infection can lead to liver fibrosis and eventually cirrhosis (typically after 2–3 decades) ◾ Once cirrhosis has developed, multiple complications can occur including: hepatocellular carcinoma (HCC) – this may occasionally precede cirrhosis jaundice ascites hepatic encephalopathy variceal bleeding death 6 How do I test for HBV? ◾ brief pre-test discussion to obtain verbal consent ◾ named testing, unless patient insists on anonymous testing ◾ serum sample to microbiology for HBsAg is the basic screen for acute or chronic HBV ◾ also request anti-HBc, to detect past infection and natural immunity, if immunisation is being considered +/- anti-HBs if there is a history of previous partial immunisation How do I interpret the test result? ◾ not as complicated as it is made out to be(!) – see section 3B1 for guidance on interpretation of results ◾ the important points to note are that: HBsAg: if +ve,