HEPATITIS A management
Hepatitis A virus infection
2.1 Aetiology
Hepatitis A is a picorna (RNA) virus. It is particularly
common in areas of the world where sanitation is poor (developing countries),
where it mainly affects children. In the developed world it is less common (352
cases reported in England and Wales, 2009) and causes disease in all age groups
[1].
2.2
Transmission:
•
Faeco-oral (via food, water, close personal
contact) [2-7].
•
Outbreaks have previously been reported in MSM,
linked to oro-anal or digital-rectal contact, multiple sexual partners,
anonymous partners, sex in public places and group sex [8-14]. Seroprevalence
studies in the UK, Spain, USA and Italy show a similar rate of hepatitis A
(IgG) antibodies in homosexual and heterosexual men who attend sexual health
clinics [15,16].
•
HIV-positive patients are not at increased risk
but may be more infectious [17,18].
•
Outbreaks have also been reported amongst PWID
[1,19], in institutions for people with learning difficulties, and in
contaminated batches of factor VIII [20-22].
•
Patients are infectious for approximately two
weeks before and one week after the period of jaundice by the non-parenteral
routes but virus can be found in blood and stool until after the serum
amino-transferase levels have peaked [23]. In HIV positive patients, HAV
viraemia may continue for over 90 days [17,18].
Incubation
Period:
15-45 days (average 28 days) [2,3,24,25]
2.4 Symptoms [24,25]
Most children and up to half of adults are
asymptomatic or have mild nonspecific symptoms with little or no jaundiceIn the more ‘typical’ case there are two phases of symptoms
-•
The
prodromal illness: flu-like symptoms (malaise, myalgia, fatigue), often
with right upper abdominal pain. This phase lasts for 3-10 days and is followed by -
•
The
icteric illness: jaundice (mixed
hepatic and cholestatic) associated with anorexia, nausea and fatigue which
usually lasts for 1-3 weeks. It can persist for 12 or more weeks in a minority
of patients who have cholestatic symptoms (itching and deep jaundice) [25].
Fever is rare in this phase.
2.5 Signs [16,24,25]
•
Non- specific in the prodromal phase.
•
Icteric phase - jaundice with pale stools and
dark urine. Liver enlargement/tenderness and signs of dehydration are also
common.
2.6 Complications
•
Acute liver failure (ALF) complicates
approximately 0.4% of cases, although 15% of patients with acute infection may
require hospital care, of whom a quarter will have severe hepatitis
(Prothrombin time P.T.> 3 seconds
prolonged or bilirubin >170moles/l) [26,27]. ALF due to
hepatitis A is more common in patients already infected with chronic hepatitis
B or C, although studies differ widely in measured rates [26,28].
•
Chronic infection (>6 months) has only been
reported in a small number of case-reports [29].
•
The overall mortality is < 0.1% although
rises to 40% in those with ALF.
Patients with ALF should be considered for liver
transplantation [26,27] .
•
Pregnancy - The infection does not have any
teratogenic effects but there is an increased rate of miscarriage and premature
labour, proportional to the severity of the illness [30,31]. There have been case reports of possible
vertical transmission [30,32,33].
2.7
Diagnosis (See also: BASHH CEG 2014 summary guidance on tests for STI)
(www.BASSH.org)
2.7.1 Serology
•
Confirmed by a positive serum Hepatitis A virus
- specific IgM (HAV-IgM) which usually remains positive for 45-60 days although
can be positive for six months or more [34,35]. HAV-IgG does not distinguish
between current or past infection and may remain positive for life [34].
•
For all patients with an undiagnosed type of
acute hepatitis also test for HBV, HCV (see sections 3.7 and 4.7.1) and
Hepatitis E (HEV). HEV in the UK is as common as HAV and most cases arise from
eating processed pork products [36]
2.7.2 Other tests
•
Typically the serum/plasma amino-transferases
(AST/ALT) is in the range 500-10,000 i.u./l, the bilirubin up to 500 moles/l, alkaline
phosphatase levels < 2x the upper limit of normal, but higher
if there is cholestasis [24,26-28].
•
Prothrombin time (PT) prolongation by more than
5 seconds is a sign of severe infection. ALF is typically associated with PT
prolongation by 50 seconds or more [24,26].
2.8 Management
2.8.1 General Advice
Employment history should be obtained so the
patient can be advised appropriately and patients should be advised to avoid
food handling and •
unprotected sexual intercourse until they have
become non-infectious (from two weeks before to one week after the onset of
jaundice) (1B) [2-14] •
Patients should be given a detailed explanation
of their condition with particular emphasis on the implications for the health
of themselves and their partner(s). This should be reinforced by giving them
clear and accurate written information (1D). [37]
•
Hepatitis A is a notifiable disease for public
health purposes in England, Wales and Northern Ireland.[38]
2.8.2 Further Investigations
Screen for other sexually transmitted infections in cases
of sexually-acquired hepatitis or if otherwise appropriate (1B)[8].
2.8.3 Acute icteric hepatitis
•
Mild/moderate (80% of all infected patients) -
manage as an outpatient emphasising rest and oral hydration (1B) [24].
•
Severe attack with vomiting, dehydration or
signs of hepatic decompensation (change in conscious level or personality) -
admit to hospital (1A) [26,27].
2.8.4 Pregnancy and Breast Feeding
•
Pregnant women should be advised of the
increased risk of miscarriage/premature labour and the need to seek medical
advice if this happens (1B) [30, 31].
•
The risk from breast feeding is uncertain
although there are no reported cases of transmission from breast milk. Even if
the infant is infected, the disease is normally mild or asymptomatic [39].
Therefore the balance of risks between infection and stopping breast feeding
should be considered on an individual basis(2C).
2.8.5 Sexual and Other Contacts
•
Partner notification should be performed for
at-risk MSM contacts (oro/anal, digital/rectal and penetrative anal sex) within
the period two weeks before to one week after the onset of jaundice (1D). This
to be documented and the outcome documented at subsequent follow-up. Other
people thought to be at risk (household contacts, those at risk from food/water
contamination ) should be contacted via the public health authorities (1D).[40]
•
Hepatitis A vaccine may be given up to 14 days
after exposure providing exposure was within the infectious period of the
source case (during the prodromal illness or first week of jaundice) (IA)
[41,42].
•
Human normal immunoglobulin (HNIG) 250-500 mg.
intramuscularly should also be considered in addition to the vaccine for
patients at higher risk of complications (concurrent chronic hepatitis B or C,
chronic liver disease, HIV+ or age >50 yo) (IA) [41]. HNIG that is effective
against HAV is in short supply in the UK and can only be obtained from Public
Health England, (England and Wales),
Health Protection Scotland or the Northern Ireland Public Health Laboratory
Belfast [41].
•
HNIG works best if given in the first few days
after first contact with an efficacy of 90%
and is unlikely to give any protection if given more than two weeks after first
exposure, but may reduce disease severity if given up to 28days after exposure
[41].
•
Patients are most infectious for two weeks
before the jaundice (i.e. before the illness is recognised) [41,42].
•
HIV-positive patients respond (as demonstrated
by antibody production) in 46-88% but titres are lower than in HIV-negative
individuals, and correlate with CD4 count [45,46].
•
If patients with a low CD4 count (<300
cells/mm3) are vaccinated, they should be revaccinated if the CD4
count rises above 500/mm3 as a result of effective HIV treatment if
the HAV IgG remains negative on retesting (1C) [45-47].
•
The combined Hepatitis A+B vaccine is given on
the same schedule as the hepatitis B vaccine and has similar efficacy to the
individual vaccines although early immunity to hepatitis B may be impaired (1
B) [48,49].
•
If an outbreak is suspected or if the index case
is a food handler, notify the local CCDC/health protection team by telephone
(1C)[38,39].
2.8.6 Follow-Up
•
See at one or two weekly intervals until
amino-transferase levels are normal (usually 4 -12 weeks) (1B).
•
Immunity is usually lifelong (1B). [34,36]
2.9 Screening and Primary Prevention
• 
Since
the outbreak of hepatitis A in 2016-17 PHE and BASHH now recommend that ‘All
MSM attending GUM and HIV clinics should be opportunistically offered a single
dose of adult monovalent hepatitis A vaccine, where available, unless they have
documented evidence of two doses of hepatitis A vaccine or of previous
hepatitis A illness’. [49b](1B)
• An
international shortage of hepatitis A vaccine led to above guidance regarding
using a single dose. Once vaccine
supplies are restored it is recommended that all unvaccinated/non-immune MSM attending GUM and
HIV clinics should be
offered full vaccination, even after the outbreak ceases (1B) (see section 2.8.5)
• Screening
for pre-existing hepatitis A exposure before vaccination has been found to be
cost-effective in one study and therefore may be performed, depending on other
factors such as funding and clinic access. (2B) [51].
• If
a hepatitis A antibody test is performed, during the outbreak situation, or if
it is likely that the MSM will not return, the first dose of vaccine should be
given be given at the same time (1B). The antibody result will aid decision
making regarding further doses. [51a]
• To
prevent sustained outbreaks, it is estimated that at least 70% of MSM should be
immune. [51b]
• If
monovalent hepatitis A or combined A+B vaccines are not available, alternative
vaccines to be used in an emergency include the paediatric formulation of the
hepatitis A monovalent vaccine at single or double dose (for HIV patients with
CD4 <500) or the combined Hepatitis A/typhoid can be used (2D)
• PWID
and people with chronic hepatitis B and C infection should also be vaccinated
(1B) [41,42].
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