Hepatitis - Self-Learning Package Flashcards
The most obvious sign of hepatitis
Jaundice with hepatic tenderness
The most important causes of viral hepatitis in the UK
Hepatitis A, B, C and E
Define subclinical illness
Infection with no symptoms
Define anicteric illness
Symptoms but no jaundice
Define icteric illness
Symptoms with jaundice
Define fulminant hepatitis
Severe jaundice with hepatic failure and high mortality
Which enzymes will be raised in acute infection? (2)
Alanine aminotransferase (ALT) Aspartate aminotransferase (AST)
Common clinical presentation of hepatitis A virus (HAV) infection in children under 5 years old
Mild, often subclinical or anicteric presentation
Mean incubation period of hepatitis A virus (HAV)
28 days (ranges from 10-50 days)
Common symptoms of hepatitis A virus (HAV) infection in adults (8)
Fever Malaise Anorexia Nausea Vomiting Upper abdominal pain Jaundice and dark coloured urine 3-10 days later
What is the main route of infection for hepatitis A virus (HAV)?
Faecal-oral
although faecal contaminated food or water may also play a part
When are patients with hepatitis A virus (HAV) most infectious?
From a week before the onset of jaundice to a few days after
What kind of antibodies are associated with hepatitis A virus (HAV) infection?
Anti-HAV IgM antibodies (usually present in serum from onset of symptoms to 3-6 months thereafter)
Anti-HAV IgA antibodies, which reflect immunity
What is the treatment for hepatitis A?
There is no specific treatment, only supportive management of symptoms
What are the three main methods of prevention of hepatitis A infection?
Good personal hygiene and sanitation
Human normal immunoglobulin (HNIG) - prophylaxis for close contacts of infected patients
Active immunisation (vaccine with killed virus)
What is the prognosis for hepatitis A?
Good - recovery can be slow but death from fulminant hepatitis is rare
There is no chronic infection or liver damage
Lifelong immunity follows infection
What are the common symptoms of acute hepatitis B infection and when can they present? (9)
Anorexia Lethargy Nausea Fever Abdominal discomfort Arthralgia Urticarial skin lesions Followed by jaundice and dark coloured urine
Can occur any time between a few weeks and 6 months after the initial infection
What is the major serum marker for identifying hepatitis B virus?
HBsAg (hepatitis B surface antigen)
What are the two main serum markers of viral replication of hepatitis B virus?
HBV-DNA (hepatitis B virus DNA)
HBeAg (hepatitis B “e” antigen - it is split off HBcAg (hepatitis B core antigen) during viral replication)
Routes of transmission of hepatitis B virus (4)
Vertical: perinatal (from mother to child during birth)
Horizontal: sexual, parenteral (any method of transmission outside the digestive system) including needlestick injury, inapparent parenteral
Why is hepatitis B virus so infectious?
It is stable and able to survive outside the human body for weeks
What are some predisposing factors to increased risk of hepatitis B virus infection in the UK? (9)
- Injecting drug use
- Multiple sexual partners
- Immigration from high endemnicity areas
- Patients with learning disabilities who live in residential care
- Patients with haemophilia or on haemodialysis
- Sexual partners of those with the above risks
- Babies born to at-risk mothers
- Tattooing/piercing with non-sterile equipment
- Medical equipment if not adequately decontaminated
How is the diagnosis of acute HBV infection made?
Serum HBsAg (unless patient presents very late or in severe fulminant acute disease) Anti-HBc antibodies are present from the end of the illness onwards, so indicate a previous acute infection
Clinical features of chronic HBV infection (5)
Persistence of HBsAg in the serum for more than 6 months
The risk of becoming chronically infected decreases with age
More common in males and immunocompromised patients
Previous mild or asymptomatic acute infection (due to defective cell-mediated immune response)
Jaundice is unusual
Prognosis of chronic HBV infection
If left untreated, progression to chronic liver disease, and thus cirrhosis or hepatoma occurs in 25% of patients
(Less commonly, can also progress to membranous glomerulonephritis and polyarteritis nodosa)
Treatment for chronic HBV infection
Entecavir or tenofovir - recommended over lamivudine, adefovir dipivoxil and telbivudine due to better efficacy and lower level of viral resistance
Liver transplantation
Prevention of chronic hepatitis B infection (4)
Active immunisation with a vaccine containing HBsAg
Passive immunisation with hepatitis B specific immunoglobulin (HBIG) - usually in combination with the vaccine
Infection control procedures
Screening of blood and transplant donors
Clinical features of hepatitis C
Acute infection:
- usually subclinical or mild
- vague symptoms of malaise, anorexia and fatigue in 20%.
Chronic infection:
- develops in 60-80%, but many have no symptoms
Known routes of transmission of hepatitis C virus (HCV) (8)
(blood-borne virus)
- Shared “works” associated with intravenous drug use (IDU) including needles, syringes, filters, spoons
- Blood products prior to heat treatment in 1989
- Blood transfusion prior to antibody screening in 1991
- Tattooing, piercing or acupuncture with non-sterile equipment
- Sexual transmission (<5%)
- Mother-to-child
- Household contacts sharing razors or toothbrushes
- Medical/dental equipment if inadequately decontaminated
Diagnostic tests available for hepatitis C virus (5)
IgG test - only of value if positive but even then, should be treated with caution HCV antigen test (confirmatory) HCV-RNA test (confirmatory) Viral RNA Sequencing for genotype
Treatment of hepatitis C
A combination pegylated alpha-interferon and ribavirin (with the addition of an HCV protease-inhibiting drug if the virus is genotype 1)
Name and describe the 4 types of response patterns to antiviral therapy
Non-responder - virus remains detectable despite therapy
Viral breakthrough - initial response followed by an increase in virus level by a factor of 10 (or 1 log unit)
Relapser - virus undetectable during therapy but detectable on stopping treatment
Sustained viral response - virus undetectable for 6 months after therapy
How can hepatitis C be prevented? (3)
Avoiding contact with infected blood (i.e. avoiding all routes of transmission)
Blood, organ and tissue screening
Covering cuts and lesions with waterproof dressings
There is no prophylaxis or vaccine available!
What is the prognosis for hepatitis C?
Of those with chronic HCV, 20-50% develop cirrhosis in 30 years
Why is hepatitis D virus (HDV or Delta Hepatitis) termed a “defective” virus?
Because it is always found with hepatitis B virus, which appears to be essential for its transmission.
What is the mean incubation period of hepatitis E virus (HEV)?
40 days (range: 3-8 weeks)
What are the clinical features of hepatitis E in developing countries?
In developing countries, infection clinically resembles hepatitis A, but there is an increased incidence of fulminant hepatitis with high mortality in pregnant women.
What are the clinical features of hepatitis E in developed countries?
Mild or subclinical in women and young people, but more severe in elderly men.
Liver failure may develop
Extra-hepatic features (arthritis, anaemia, neurological manifestations) may predominate over hepatic features.
In most cases, acute infection is self-limiting.
What are the routes of transmission of hepatitis E virus (HEV)? (4)
Sewage-contaminated drinking water and probably food
Undercooked pork products (85% of pigs in the UK are infected)
Occupation related (e.g. abattoir workers)
Blood exposure
Diagnostic tests for hepatitis E virus (HEV)
There are tests for IgG, IgM and HEV-RNA but it is not known if protective immunoglobulins develop against future infection
Treatment for hepatitis E
No licensed treatment
In the immunocompromised, reduce immunosuppression if possible, but if not (or in severe infection), give ribavirin monotherapy
What are the methods of prevention of hepatitis E?
Good hygiene
Good sanitation
Adequate cooking of food
Passive immunisation with human normal immunoglobulin (HNIG) - doesn’t protect tropical travellers
(Active immunisation with a subunit vaccine is available in China)
