Pyogenic liver abscess
Pyogenic liver abscess is a polymicrobial hepatic infection that most often seeds from the biliary tract or the portal circulation, presenting with fever, right upper quadrant pain, and a cholestatic liver profile. Diagnosis rests on contrast imaging plus culture, and treatment combines empiric broad-spectrum antibiotics with image-guided drainage for abscesses at or above 3 to 5 cm.
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What this article covers
- Overview
Definition: pyogenic liver abscess is a bacterial infection of the hepatic parenchyma that forms a pus-filled cavity, most commonly seeded from an intra-abdominal or biliary source rather than arising primarily in the liver.
- Epidemiology
Most common visceral abscess: pyogenic liver abscess is the most frequent type of visceral abscess encountered clinically.
- Risk factors
Biliary tract disease: cholangitis, choledocholithiasis, biliary strictures, and instrumentation (ERCP, stents, biliary-enteric anastomoses) provide a direct route of ascending infection (acute cholangitis).
- Pathophysiology
Seeding route determines the organism mix: bacteria reach the liver by direct extension from an obstructed, infected biliary tree, by portal venous drainage from an intra-abdominal infection, or by hepatic arterial bacteremia.
- Clinical features
Fever: the most consistent finding, often with chills.
- Differential diagnosis
Amebic liver abscess: typically a single right-lobe lesion in a patient from or having traveled to an endemic area (Central or South America, other developing regions), confirmed by Entamoeba…
- Diagnosis
Confirmed by a hepatic collection plus culture: the diagnosis is established by demonstrating a discrete hepatic fluid collection together with organisms recovered from blood culture or aspirate…
- Management
Start empiric broad-spectrum IV antibiotics as soon as cultures are drawn, covering streptococci, enteric gram-negative bacilli, and anaerobes, before or concurrent with aspiration.
- Complications
Septic shock: an untreated or inadequately drained abscess can progress to systemic sepsis and septic shock.
- Prognosis
Outcome depends on timely source control: most patients recover fully with prompt antibiotics plus drainage when the abscess is 3 cm or larger; delayed diagnosis or delayed drainage increases the risk of sepsis and death.
- Prevention
Prompt treatment of biliary obstruction: timely ERCP-based decompression and complete extraction of common bile duct stones for choledocholithiasis or biliary stricture prevents ascending infection that can seed the liver.
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