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Flashcards in Hepatitis Deck (57)
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1
Q

what do hepatitis cause?

A

inflammation of the liver primarily

2
Q

how does Hepatitis A spread?

A

faecal-oral
poor hygiene/overcrowding
Some cases imported

3
Q

what groups does hepatitis A cluster in?

A

gay men

people who inject drugs

4
Q

what are the clinical effects of hepatitis A?

A

acute hepatitis, no chronic infection

peak incidence of symptomatic disease in older children/young adults

5
Q

what is the lab confirmation of acute infection of Hep A?

A

clotted blood for serology (gold top container)

  • same sample for all causes of viral hepatitis
  • Hep A IgM (detectable at onset of illness)
6
Q

how is Hep A controlled?

A
hygiene
vaccine prophylaxis (only for at risk - travel, risk groups)
7
Q

where is Hep E most common?

A

tropics

has become more common then Hep A in the UK

8
Q

what is Hep E like clinically?

A

like Hep A

9
Q

how does Hep E spread?

A

faecal-oral

often zoonosis in the UK (eg infected pigs, rabbits, deer)

10
Q

which hepatitis is a real concern in pregnant women?

A

Hep E genotype in tropics causes severe disease in pregnant women

11
Q

who is more likely to get a chronic Hep E infection?

A

immunocompromised

normal people get acute

12
Q

hep D only occurs in people with Hep B, true or false?

A

true

13
Q

what is Hep D?

A

parasite of a parasite
exacerbates Hep B
rare in scotland

14
Q

how is Hep B spread?

A

sex
mother to child at delivery
blood to blood contact

15
Q

who is at a higher risk of Hep B in the UK?

A

people born in areas of intermediate/high prevalence (outside NW Europe)
multiple sexual partners
people who inject drugs
children of infected mothers

16
Q

Hep B and hep C are spread similarly, true or false?

A

true

17
Q

is there a Hep B vaccine?

A

yes

given to many children in first year of life

18
Q

how does lab confirm hep B?

A

hep B surface antigen in blood (HBsAg)
- present for >6 months = chronic
- HBeAg = highly infectious individuals
- Hep B virus DNA = high titre in highly infectious individuals, predicts risk of chronic liver disease and monitors therapy
Hep B IgM most likely present in recently infected cases
Anti HBs present in immunity/vaccinated

19
Q

does everyone with chronic infection have chronic liver disease?

A

no

20
Q

what are the 4 phases of chronic infection?

A
immune tolerance
immune clearance
immune control
immune escape
complex and dynamic relationship between virus and immune system so test values (ALT, HBV DNA etc) rise and fall
21
Q

how is Hep B controlled?

A

minimise exposure
- safe blood
- safe sex
- needle exchange
- prevent needlesticks
- screen pregnant women
2 pre-exposure vaccination strategies used:
- vaccinate all children born since August 2017
- vaccinate at risk older children and adults
Post-exposure prophylaxis (eg. after sex with infected)
- vaccine
- plus HBIG (hyperimmune hep B immunoglobulin)

22
Q

can a vaccine prevent Hep B infection after sex with an infected person? How?

A

Yes

Long incubation period

23
Q

how is Hep C spread?

A

similar to Hep B

less easily by sex than Hep B

24
Q

hoes Hep C have a vaccine?

A

no

25
Q

how common is chronic infection in Hep C?

A

75% of cases

not dependant on age at time of infection

26
Q

how does age affect likelihood of getting symptoms in Hep A?

A

older at time of infection = more likely to get symptoms

27
Q

what defines a chronic infection of hepatitis?

A

6 months infection

28
Q

Is spontaneous cure common in Hep B?

A

not uncommon

even after many years of infection

29
Q

is spontaneous cure common in Hep C?

A

once chronic infection established, never seen

30
Q

what is the time frame from infection to cirrhosis?

A

usually >20 years

31
Q

what is the time frame from infection to cancer?

A

> 30 years

32
Q

what is the most common hepatitis in Tayside?

A

C

some reduction in recent years

33
Q

Hep E is very severe, true or false?

A

false

usually mild, rarely causes death

34
Q

how does lab confirm hep C?

A
test if at risk or with signs of chronic liver disease
test for antibody to Hep C virus
- negative = not infected
- positive = past or active infection
if positive
- test for Hep C virus RNA by PCR
- positive = active infection
- negative = no infection
35
Q

how is Hep C controlled?

A

no vaccine

prevent needle sharing etc

36
Q

how is acute viral hepatitis managed?

A
only if symptomatic
no antivirals given
monitor for encephalopathy
monitor for resolution
- of Hep B, C or E if immunocompromised
notify public health
immunise contacts
test for other infections at risk of (eg. HIV, syphilis if having unprotected sex)
vaccinate against other infections if at risk
37
Q

how is chronic viral hepatitis managed?

A
antivirals
- for Hep B and Hep C
vaccination
- other hep infections
- if cirrhotic: influenza, pneumococcal
infection control
reduce alcohol
hepatocellular carcinoma awareness/screening
- important for patients with cirrhosis
- serum alpha fetoprotein (AFP) and ultrasonography
38
Q

what does ultrasound of liver look for?

A

nodules that could be cancer

39
Q

what classifies a chronic infection?

A

HCV RNA present and genotype known
HBsAg and Hep B DNA present
> 6 months

40
Q

what indicates risks of complications of treatment?

A
inflammation/fibrosis, cirrhosis sought, mainly in hep B
high ALT (sign of inflammation)
41
Q

when are people fit for treatment?

A

established cirrhosis more difficult to treat but are treated as priority
liver cancer = contraindication
HIV co-infection = urgent so stabilise HIV

42
Q

when do you treat hepatitis?

A
before complications
when evidence of inflammation (high ALT)
 -with advanced fibrosis, not yet cirrhosis and cirrhosis are priority
when patient is ready
clinical priority
43
Q

what is interferon alpha?

A

used in Hep B
part of innate immune response to viral infection
given by injection as pegylated interferon (peginterferon)
complex mode of action, including as immune adjuvant
used less due to side effects

44
Q

what are the side effects of peginterferon?

A
common
- flu like symptoms
less common
- thyroid disease
- autoimmune disease (SLE etc)
- psychiatric disease
- so if already have these don't use
45
Q

what are the options for Hep B treatment?

A
usually option 1
1:
- suppressive antiviral drug
- safe and increasing range
- only suppress don't cure
- resistance can occur
2:
- peginterferon alone
- can cure but not always
- side effects
- good in HBsAg and HBeAg +ve people with good chance of cure
46
Q

what are the aims of Hep B therapy?

A
virological
- reduce HBV DNA
- loose HBeAg
- loose HBsAg (cure)
improve liver biochem
reduce infectivity
reduce progression to cirrhosis/cancer etc
reduce mortality
47
Q

what are the aims of Hep C treatment?

A

loss of HCV RNA in blood sustained to 6 months after end therapy

  • known as sustained virological response (SVR)
  • relapse after SVR is rare but reinfection can happen
48
Q

what is the choice of antiviral regime for HCV based on?

A
virus genotype
patient's interferon response genes
stage of disease
past treatment experience
likelihood of side effects
cost effectiveness
49
Q

what is the benchmark aim for HCV therapy?

A

> 90% SVR

50
Q

what do antivirals end in?

A

“…vir”

51
Q

can HCV be cured with oral antivirals?

A

yes

52
Q

when is a chronic Hep B infection more likely?

A

chronic infection more likely if first exposure in childhood

53
Q

IgG +ve, RNA -ve?

A

Past infection

54
Q

IgG +ve, RNA +ve?

A

current infection

55
Q

list a side effect of ribavirin?

A

anaemia

56
Q

what are the results of SVR?

A
improved liver biochem
reduced infectivity
reduced incidence of cancer
reduced mortality
improved hisopathology
rare relapse
57
Q

what is the standard for Hep C treatment?

A

oral, interferon free courses of 2 or 3 antivirals for up to 12 weeks with high SVR

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