Hepatobiliary Infections, Parasitic

• • Etiologies include:

  • -Amebic

    -Echinococcal

    -Schistosomal

  • Risk factors for amebic abscess:

  • -HIV

    -Travel to high prevalence area

    -Alcoholism

  • Hydatid cysts:

  • -Liver (50-70% of cases)

    -Lung (20-30% of cases)

Epidemiology

• • Schistosomal infection major cause of portal hypertension worldwide

Symptoms and Signs

• • Fever

  • Right upper quadrant pain

  • Jaundice

  • Dyspnea

  • Diarrhea in 33% with amebic abscess

  • Anaphylaxis (hydatid cyst)

  • Palpable hepatic mass (hydatid cyst)

  • For schistosomal disease:

  • -Maculopapular rash

    -Lassitude

    -Anorexia

    -Diarrhea

    -Headache

    -Fevers

    -Hepatomegaly

    -Splenomegaly

    -Lymphadenopathy

    -Variceal hemorrhage

Laboratory Findings

• • Leukocytosis

  • Elevated alkaline phosphatase

  • Elevated transaminases

  • Hypoalbuminemia rare for amebic abscess

  • Entamoeba histolytica serologic studies (positive in 95% of cases) in amebic abscess

  • Hydatid serologic studies (positive in > 80% of cases)

  • Schistosomal ova in feces

  • Eosinophilia in hydatid disease

Imaging Findings

• • CT scan and US for amebic abscess: Unifocal or multifocal fluid filled areas in liver with peripheral contrast enhancement (not distinguishable from pyogenic)

  • CT scan for hydatid cyst: Presence of daughter cysts within parent cyst accompanied by calcification

• • Pyogenic abscess

• • History and physical exam

  • CBC

  • Liver function tests

  • Abdomen CT with contrast

  • E histolytica serologic studies (positive in 95% of cases) in amebic abscess

  • CT-guided aspiration

  • Hydatid serologic studies (positive in > 80% of cases)

  • Schistosomal ova in feces

Surgery

• • CT-guided drainage of hydatid cysts

Medications

• • Metronidazole with or without chloroquine for amebic abscess

  • Albendazole for 8 weeks for hydatid disease

  • Praziquantel for schistosomiasis

Complications

• • Rupture of amebic abscess or hydatid cyst

  • Secondary bacterial infection of amebic abscess or hydatid cyst

  • Hydatid cyst spilling into open peritoneal cavity

Prevention

• • Improved sanitation in areas of high risk for E histolytica infection

References