Hepatic abscess

Background

Bile duct and pancreas anatomy. 1. Bile ducts: 2. Intrahepatic bile ducts; 3. Left and right hepatic ducts; 4. Common hepatic duct; 5. Cystic duct; 6. Common bile duct; 7. Sphincter of Oddi; 8. Major duodenal papilla; 9. Gallbladder; 10-11. Right and left lobes of liver; 12. Spleen; 13. Esophagus; 14. Stomach; 15. Pancreas: 16. Accessory pancreatic duct; 17. Pancreatic duct; 18. Small intestine; 19. Duodenum; 20. Jejunum; 21-22: Right and left kidneys.

Inferior view of the liver with surface showing lobes and impressions.

Liver vascular anatomy.

• Uncommon overall - usually occurs in right liver lobe
  • More abscesses → more severe disease
• History of camping is common
  • Endemic of Midwest

Types

• Pyogenic (80%)
  • Most common cause
  • Associated with biliary tract obstruction (most common), cholangitis, diverticulitis, pancreatic abscess, appendicitis and inflammatory bowel disease.
  • Possible arterial hematogenous seeding: sepsis, direct trauma or instrumentation
  • Usually polymicrobial
• Amebic (10%)
  • E. histolytica most common
  • Usually not septic and sick, rarely needs drainage
• Fungal (<10%), candidal
• Hydatid cyst (echinococcosis)
  • Associated with sheep farmers

Clinical Features

• RUQ pain
• High fever
• Nausea, vomiting, anorexia
• Clay-colored stool
• Dark urine
• Jaundice - seen with pyogenic, as opposed to amebic
• Often with right pleural effusions

Differential Diagnosis

Hepatic abscess

• Pyogenic abscess
  • Aerobic: Escherichia coli, Klebsiella, Pseudomonas
  • Anaerobic: Enterococcus, bacteroides, anaerobic streptococci
• Echinococcosis
• Amebiasis
• Benign cysts/malignancy
• Tuberculosis
• Mycosis

RUQ Pain

• Gallbladder disease
  • Symptomatic cholelithiasis (biliary colic)
  • Choledocholithiasis
  • Acute cholecystitis
  • Ascending cholangitis
  • Acalculous cholecystitis
• Pancreatitis
• Acute hepatitis
• Pancreatitis
• GERD
• Appendicitis (retrocecal)
• Pyogenic liver abscess
• Bowel obstruction
• Cirrhosis
• Budd-Chiari syndrome
• GU
  • Pyelonephritis
  • Kidney stone
  • Fitz-Hugh-Curtis Syndrome
• Other
  • Hepatomegaly due to CHF
  • Peptic ulcer disease with or without perforation
  • Pneumonia
  • Herpes zoster
  • Myocardial ischemia
  • Pulmonary embolism
  • Abdominal aortic aneurysm

Evaluation

Liver abscess on axial CT image: a hypodense lesion in the liver with peripherally enhancement.

A large pyogenic liver abscess.

Work-up

• CBC - Elevated white blood count (70-80%)
• BMP
• LFTs - Elevated alkaline phosphatase levels (90%)
• Coags
• Blood cultures
• Amebic and echinococcal serologies
• Ultrasound (80-100% sensitivity)
• CT abd/pelvis (Imaging study of choice)
  • Triphasic CT scan to define the proximity of the abscess to the major branches of the portal and hepatic veins

Evaluation

• Diagnosis usually made on imaging studies

Management

• IV antibiotics
  • Two or more antibiotics
    • Gram Negs: third or fourth generation cephalosporin (ceftriaxone) or aminoglycoside
    • Gram Pos: penicillin for streptococcal species (ampicillin)
      • For penicillin allergic, use fluoroquinolones
    • Anaerobes: metronidazole or clindamycin

• Diagnostic aspiration and drainage of the abscess followed by placement of drainage catheter
  • Sonographic guidance for small or superficial abscesses
  • CT guidance for deep or multiple abscesses
• Surgical drainage
  • Abscesses > 5cm
  • Abscesses not amenable to percutaneous drainage due to location
  • Failure of percutaneous aspiration and drainage
  • Coexistence of inra-abdominal disease that requires surgical management

Disposition

• Admit for IV antibiotics and surgical drainage

See Also

• Right upper quadrant abdominal pain
• Amebiasis