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200 Chapter 5: Hepatic, biliary and pancreatic systems

Table 5.5 Hepatotrophic viruses
Virus Type Transmission Incubation period
Hepatitis A virus (HAV) ssRNA faecal/oral ∼1month
Hepatitis E virus (HEV) ssRNA faecal/oral ∼1–2 months
Hepatitis B virus (HBV) dsDNA blood/sexual ∼2–3 months
Hepatitis D virus (HDV) Defective RNA blood/sexual Needs HBV for replication
Hepatitis C virus (HCV) ssRNA blood/sexual ∼2–3 months

β-blockers may be used as secondary prophylaxis ei- Geography

ther in combination with endoscopic therapies or Endemic in developing countries, with exposure in early
alone. If they are used alone, it is recommended that childhood being common and adults universally im-
hepatic venous pressure gradient is measured to con- mune. In developed countries, most cases are sporadic
firm the success of treatment. and the numbers are declining.
TIPSS is more effective than endoscopic treatment in

Aetiology/pathophysiology
reducingvaricealrebleedingbutdoesnotimprovesur-
ssRNA enterovirus of the picorna group. HAV is trans-
vival and is associated with more encephalopathy.
mitted by the faecal–oral route (especially in seafood)
and has an incubation period of 2–6 weeks. It is infec-
Prognosis tious from 2 weeks before clinical symptoms until a few
There is a 50% mortality in patients presenting for the days after the onset of jaundice. The mechanism of hep-
first time with bleeding oesophageal varices. Prognosis atocyte necrosis is unclear; the virus is not cytopathic in
is worse in patients with high Child–Pugh grading (see tissue culture.
page 196). Without treatment to prevent recurrence two
thirds of patients re-bleed whilst in hospital and 90% Clinical features
re-bleed within a year. Exposure and infection in early childhood is usually
asymptomatic.Symptomsandseverityincreasewithage.
A history of contact/travel abroad may be found, al-
Viral hepatitis thoughmanyasymptomaticcasesoccur.Patientspresent
with a prodromal phase (malaise, anorexia, nausea, aver-
Definition sion to fatty foods and cigarettes) lasting about a week.
The term viral hepatitis usually refers specifically to the Jaundice appears after the prodromal phase and lasts
diseases of the liver caused by the hepatotropic viruses, about 2 weeks. The liver may be palpably enlarged and
which include hepatitis A, B, C, D, E (see Table 5.5). tender.
Other viruses such as the Epstein–Barr virus and cy-
Complications
tomegalovirus may cause acute hepatitis.
Intrahepatic cholestasis resulting in dark urine and pale
stools. Rarely, aplastic anaemia in children, which has
Pathophysiology a high mortality. Very occasionally fulminant hepatic
The hepatotrophic viruses can cause a range of failure occurs.
pathologically and clinically evident liver disease (see
Fig. 5.6). Investigations
Diagnosed by the finding of HAV-specific IgM. IgG
anti-HAV appears as IgM, disappears over the follow-
Hepatitis A ing months and persists for years, giving immunity.
Definition Management
Hepatitis A virus (HAV) is one of the hepatotrophic Treatment is supportive. Prevention by HAV vaccina-
viruses, which cause viral hepatitis. tion, a killed whole virus vaccine.