Hepatitis A Flashcards
Aetiology of hepatitis A
Hepatitis A is a picorna (RNA) virus
particularly common in areas of the world with poor sanitation where it mainly affects children
Transmission of Hep A
- Faeco-oral (via food, water, close personal contact)
- Outbreaks reported in MSM linked to: > oro-anal contact > digital-rectal contact > multiple sexual partners > anonymous partners > sex in public places > group sex
Impact of HIV on hepatitis A
HIV-positive patients are NOT at increased risk
but MAY be more infectious
HAV viraemia may continue for over 90 days
Duration of infectivity of hepatitis A
approximately 2 weeks before and 1 week after the period of jaundice
but virus can be found in blood and stool until after the serum amino-transferase levels have peaked
Incubation Period of hepatitis A
15-45 days
average 28 days
Symptoms of Hep A
asymptomatic - Most children + 50% adults
two phases of symptoms -
> prodromal illness = flu-like symptoms (malaise, myalgia, fatigue) +/- RUQ pain
lasts for 3-10 days
followed by -
> icteric illness = jaundice, anorexia, nausea, fatigue
lasts for 1-3 weeks
Signs of Hep A
Non- specific prodrome
Icteric phase - jaundice, pale stools and dark urine.
Liver enlargement / tenderness
signs of dehydration
Complications of Hep A
Acute liver failure - 0.4%
Hospital care required - 15%
Chronic infection (>6 months) - case-reports only
mortality is < 0.1% (but 40% if ALF develops)
Impact of Hep A on pregnancy
No teratogenic effects
increased rate of miscarriage and premature labour
Diagnosis of Hep A
positive serum Hepatitis A virus - specific IgM (HAV-IgM)
Usually remains positive for 45-60 days
does not distinguish between current or past infection and may remain positive for life
Additional tests advised for a patient with Hep A / being tested for Hep A
HBV HCV Hepatitis E (HEV) as common as HAV in the UK - most cases arise from eating processed pork products HIV STS Sexual health screen
LFTS (AST/ALT / bilirubin)
Prothrombin time
What prothrombin time usually indicates acute liver failure
50 seconds or more
General Management Advice for patients with Hep A
Employment history - advise to avoid food handling
Avoid UPSI
until they are non-infectious = from 2 weeks before to 1 week after onset of jaundice
notifiable disease for PHE
Management of mild icteric hepatitis A
80% = Mild / moderate - manage as an outpatient - rest and oral hydration
IF severe vomiting / dehydration / signs of hepatic
decompensation - admit to hospital
Management of hepatitis A in pregnancy / breastfeeding
Advise of the increased risk of miscarriage / premature labour
Risk from breast feeding is uncertain - no reported
cases
If the infant is infected - usually mild / asymptomatic
Partner notification for Hep A
PN for at-risk MSM contacts
2 weeks before to 1 week after the onset of jaundice
+ other people at risk (household contacts / those at risk from food / water contamination)
Management of a patient exposed to Hep A
Hepatitis A vaccine - given up to 14 days after exposure - 0 and 6-12 month doses
Consider Human normal immunoglobulin (HNIG) 250-500 mg IM
in addition to the vaccine for patients at higher risk of complications (concurrent chronic HBV or HCV / chronic liver disease / HIV+ / age >50 yo)
How can Human normal immunoglobulin (HNIG) be obtained
can only be obtained from Public Health England
HNIG that is effective against HAV is in short supply in the UK
Hepatitis A vaccine schedule
doses at 0 and 6-12 months
95% protection for at least 10 years
How long does Hep A vaccination offer protection for?
95% protection
for at least 10 years
Follow up of a patient diagnosed with Hep A
See at 1 or 2 weekly intervals
until amino-transferase levels are normal
usually 4 -12 weeks
Immunity following a Hep A infection
Immunity is usually lifelong
Which patients should be offered the Hep A vaccination in GUM clinics
and why
All non-immune MSM - opportunistically offered Hep A vaccination course
due to an outbreak of hepatitis A in 2016-17
+ people who inject drugs
+ patients with chronic Hep B or C
+ patients with HIV
