Liver Abscesses & Cysts

Question 1

Definition (abscess)

Answer 1

liver infection resulting in a walled off collection of pus

Question 2

Definition (cyst)

Answer 2

liver infection resulting in a walled off collection of cyst fluid

Question 3

Aetiology

Answer 3

• Pyogenic (producing pus)
o Escherichia coli
o Klebsiella
o Enterococcus
o Bacteriodes
o Streptococci
o Staphylococci
o 60% are caused by biliary tract disease (e.g. gallstones, strictures, congenital
cysts)
o 15% have unknown cause

• Amoebic abscess
o Caused by Entamoeba histolytica

• Hydatid cyst (cyst containing watery fluid):
o Caused by tapeworm Echinococcus granulosis

• Other causes: TB

Question 4

Epidemiology

Answer 4

• Pyogenic is the most common type of liver abscess in the industrialised world
• Amoebic liver abscess - most common WORLDWIDE
• Hydatid cysts - common in sheep-rearing countries

Question 5

Presenting symptoms

Answer 5

• Fever
• Malaise
• Nausea
• Anorexia
• Night sweats
• Weight loss
• RUQ/epigastric pain that may be referred to the shoulder (due to irritation of the
diaphragm)
• Jaundice
• Diarrhoea
• Pyrexia of unknown origin
• IMPORTANT: make sure you ask about foreign trave

Question 6

Signs on physical examination

Answer 6

• Fever - continuous or spiking
• Jaundice
• Tender hepatomegaly (right lobe affected more than left)

• Right lung base:
o Dullness to percussion
o Reduced breath sounds
o Due to reactive pleural effusion

Question 7

Investigations (bloods)

Answer 7

o FBC
• Mild anaemia
• Leukocytosis
• High eosinophils (if hydatid disease)

o LFTs
• High ALP
• High bilirubin

o High ESR and CRP

o Blood cultures

o Amoebic and hydatid serology

Question 8

Investigations (other)

Answer 8

• Stool MC&S - for E. histolytica
• Liver US or CT/MRI - localises structure of mass
• CXR - check for right pleural effusion or atelectasis, raised hemidiaphragm

• Aspiration and culture of the abscess material
o Most pyogenic liver abscesses are polymicrobial
o Amoebic abscesses have fluid of necrotic hepatocytes and trophozoites