Hepatitis C
From Ganfyd
Web Resources for Hepatitis C
ICD 10 code: B17.1 (acute), B18.2( chronic)
Relevant Clinical Literature
UK Guidance
Other Wikis
Medpedia on Hepatitis C (Less technical, good quality control)
Wikipedia on Hepatitis C (Less technical, ? quality control)
Contents |
Introduction
Similar to, but far less infectious than Hepatitis B. Asymptomatic for many years, it eventually leads to cirrhosis and hepatocellular carcinoma. It is particularly important among intravenous drug users, with over 70% of users positive in Glasgow[1], and about 53% across England and Wales.[2]
Aetiology
Hepatitis C infection is caused by the hepatitis C virus(HCV). HCV is an RNA virus. It is a flavivirus. There are 6 main genotypes of HCV, with distinct geographical distributions. Unlike Hepatitis B, it only appears to be transmitted by blood, sexual contact or vertically.
Clinical
HCV can cause an acute hepatitis with fever and jaundice. This is a relatively rare presentation. Most cases in the UK are asymptomatic, and only diagnosed after an incidental finding of deranged LFTs. Infection may be cleared spontaneously (sometimes even antibody is lost, eventually), but most go on to have chronic infection. Years may go by before there is progression to cirrhosis or hepatocellular carcinoma.
Maternal hepatitis C
Investigations
Blood tests
- Hepatitis C serology - seroconversion occurs 2-6 months after initial infection.
- Hepatitis C RNA PCR qualitative or quantitative - shows on-going viral replication.
- LFTs
- HCV Genotype
Blood tests will differentiate:
- acute infection (PCR positive without antibody), which requires referral for specialist treatment.
- chronic infection (PCR and antibody positive)
- previous infection (PCR negative but antibody positive) -care is needed after initial infection, where RNA levels may oscillate. Hence a negative PCR should always be confirmed with a second sample, especially since the date of infection may not be known. If persistently negative, no further treatment is required.
Radiology
Liver ultrasound
Pathology
Biochemical and radiological tests are poorly predictive of liver fibrosis, and can only really differentiate mild disease from cirrhosis. So liver biopsy may be required to establish severity, especially when treatment is being considered. Where a patient has genotype 2 or 3, pre-treatment biopsy may not be necessary given the high rates of response.
Progression
The risk of progression to cancer or cirrhosis is difficult to quantify on an individual basis. Age and sex seem to be relevant, with older patients and men having a higher risk, but studies have addressed different populations. Moderate or higher alcohol intakes, smoking and HIV or HBV coinfection all increase risk. Genotype, surprisingly, does not appear to make a difference.
Treatment
Medical
- Vaccination against hepatitis A (increased risk of acute fulminant liver failure) and B (increased risk of progression)
- Nutrition
- Anti-viral treatment of hepatitis C should be initiated and supervised by a hepatologist, gastroenterologist or infectious diseases physician. Duration of treatment is determined by the HCV genotype - genotype 1 requires a longer course than those with types 2 or 3. Treatment can continue for between 6 to 12 months. The drugs used are (pegylated) interferon and ribavirin. The objective of treatment is sustained viral response ie undetectable RNA at 6 months.
Surgical
- Patients with hepatitis C virus and concurrent operable hepatocellular carcinoma should be offered liver transplantation. *Patients with HCV associated chronic liver failure should be offered liver transplantation.
Surveillance and follow up of cases
Standards for surveillance and follow up of hepatitis B & C have been published by the Health Protection Agency.[3] Screening for hepatocellular carcinoma with alpha feto protein levels and ultrasound is only really of value in patients with established cirrhosis, and probably needs to be done 6 monthly.
Prevention
There is currently no vaccine for HCV. Prevention occurs on a population level by the screening of donated blood/blood products for HCV. See maternal hepatitis C for vertical transmission.
Post exposure prophylaxis
Early treatment of new infections where spontaneous clearance does not take place has been validated, but is not yet standard practice.[4]
Notification
All forms of viral hepatitis are notifiable diseases.
ICD code
External links
- SIGN guideline (2005) website
- Hepatitis C information at the Health Protection Agency website
- US CDC website.
- Viral hepatitis prevention board
References
- ↑ Hutchinson SJ, Roy KM, Wadd S, Bird SM, Taylor A, Anderson E, Shaw L, Codere G, Goldberg DJ. Hepatitis C virus infection in Scotland: epidemiological review and public health challenges. Scottish medical journal. 2006 May; 51(2):8-15.
- ↑ Health Protection Agency, Health Protection Scotland, National Public Health Service for Wales, CDSC Northern Ireland, CRDHB, and the UASSG. Shooting Up; Infections among injecting drug users in the United Kingdom 2004. An update. London: Health Protection Agency, October 2005. (http://www.hpa.org.uk/infections/topics_az/injectingdrugusers/shooting_up.htm)
- ↑ Health Protection Agency. Standards for surveillance and follow up of hepatitis B & C. April 2006.
- ↑ Santantonio T, Fasano M, Sinisi E, Guastadisegni A, Casalino C, Mazzola M, Francavilla R, Pastore G. Efficacy of a 24-week course of PEG-interferon alpha-2b monotherapy in patients with acute hepatitis C after failure of spontaneous clearance. Journal of hepatology. 2005 Mar; 42(3):329-33.(Link to article – subscription may be required.)
