1. Liver
Abscess
Lecture 23 1

2. Definition
• A liver abscess is a pus-filled mass
inside the liver.
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3. Types
There are three major forms of liver abscess,
classified by etiology:
1.Pyogenic liver abscess, which is most often
polymicrobial, accounts for 80% of hepatic
abscess cases in the United States.
2.Amoebic liver abscess due to Entamoeba
histolytica accounts for 10% of cases.
3.Fungal abscess, most often due to
Candida species, accounts for less than 10%
of cases.
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4. Causes & risk
factors• Common cause:
• 1. Biliary tract infection
• 2. Inf from GIT or Pelvic organs
• 3. Unknown
• 4. Hematog. Spread secondary to bacteremia
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5. Risk Factors
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Developed countries
Developing countries

6. Debilitating disease with immune
deficiency is a common setting-e.g.,
• Extreme old age
• Immunosuppression
• Cancer chemotherapy with marrow failure
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7. The organism reach the liver through
one of the following pathways:
• (1) ascending infection in the biliary tract
(ascending cholangitis);
• (2) vascular seeding, either portal or arterial,
predominantly from the GIT
• (3) direct invasion of the liver from a nearby
source; or
• (4) a penetrating injury.
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9. Pyogenic Liver Abscess
• In developed countries
• bacterial abscesses are more
common, representing a complication of an
infection elsewhere.
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10. Causitive organisms
• They are generally produced by
• gram-negative bacteria such as
• Escherichia coli and
• Klebsiella sp.
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12. Jaundice, Fever, Abd pain
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15. Amebic Liver Abscess
• In developing countries liver abscesses are
common; most result from
• parasitic infections, such as
• emebic, echinococcal, and (less commonly)
other protozoal and helminthic organisms.
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22. Morphology
Number: Solitary or multiple
Size: millimeters –centimeters
Bacteremic spread through the arterial or
portal system tends to produce
multiple small abscesses,
Direct extension and trauma usually cause
solitary large abscesses.
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23. • Biliary abscesses, which are usually
multiple, may contain purulent material from
adjacent bile ducts.
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24. • Gross and microscopic:
• necrotic tissue with abundant neutrophils.
• The causative organism can occasionally be
identified in the case of fungal or parasitic
abscesses.
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25. • On rare occasions, abscesses located in the
subdiaphragmatic region, particularly amebic, may
burrow into the thoracic cavity to produce
empyema or a lung abscess.
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26. • Rupture of subcapsular liver abscesses can
lead to peritonitis or localized peritoneal
abscesses.
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27. • Echinococcal infection has a
characteristic cystic structure;
• the wall is laminated (coated), and
• hooklets and intact organisms can be
identified.
• Calcification in the cystic wall is common.
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29. Key points
• A liver abscess is a pus-filled cavity within the liver, usually caused by
a biliary tract source; occasionally, multiple cavities are seen
• Origin may be pyogenic, amebic, or (rarely, and usually in severely
immunocompromised patients) fungal
• Clinical presentation is with fever and abdominal pain but is
frequently nonspecific, without localized right upper quadrant
symptoms
• Computed tomography (CT), both with and without intravenous and
oral contrast, and ultrasound are the imaging studies of choice
• Treatment involves antimicrobial therapy with or without
percutaneous or surgical drainage
• Liver abscess is almost uniformly fatal if left untreated. Timely
treatment reduces mortality to 5% to 30%
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