Occurs via portal vein, arterial system, or bile ducts
Etiology/Pathogenesis
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Bacterial pathogens most common in Western countries
Klebsiella pneumoniae is now most common pathogen, followed by
Escherichia coli
Anaerobes are isolated in up to 25% of cases
Significant number are cryptogenic
Clinical Issues
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Diabetes is major risk factor
Other associated conditions include intraabdominal infections, biliary disease, malignancy, cirrhosis
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Presentation includes fever, chills, RUQ pain
Elevated WBC count, ESR, CRP, bilirubin, alkaline phosphatase, transaminases
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Percutaneous drainage and antibiotics are mainstay of therapy
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Major complication is spread of infection
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Mortality ∼ 15% overall
Imaging
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Ultrasound &/or CT mainstay of diagnosis
Macroscopic
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Most abscesses are solitary; multiple abscesses occur in 25-45% of cases
Right lobe most frequent site
Microscopic
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Abundant neutrophils, fibrin, and bile with associated fibrosis
TERMINOLOGY
Definitions
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Infection featuring localized accumulation of pus with surrounding inflammation and fibrosis
Occurs via portal vein, arterial system, or bile ducts
ETIOLOGY/PATHOGENESIS
Predisposing Conditions
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Diabetes is major risk factor
Other predisposing conditions include malignancy, alcohol abuse, cirrhosis, hypertension, recent surgery, immunosuppression
Abscesses secondary to
Yersinia enterocolitica or
Yersinia pseudotuberculosis are often associated with underlying hemochromatosis
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Biliary disease
Including biliary ischemia secondary to surgery or ablative procedures
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Intraabdominal infections
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Significant number are cryptogenic
.
. The necrotic parenchyma is infiltrated with neutrophils.
, as seen in this actinomycotic abscess. Marked acute and chronic inflammation are also present.
