Amoebic liver abscess

Introduction

Amoebic liver abscess is a collection of typically brownish coloured fluid in the liver, occurring often as a single mass in the right lobe and a complication of intestinal infection with Entamoeba histolytica.
Lung, heart and brain infections are uncommon sequelae.
Occasionally, pyogenic abscesses may have a similar clinical presentation.
Treatment of amoebic abscesses should be initiated with a tissue agent active against the trophozoite form followed by a luminal agent to eliminate intra-luminal cysts.

Causes of amoebic liver abscess

Amoebic liver abscess is caused by Entamoeba histolytica

Symptoms of amoebic liver abscess

The following are the symptoms of ALA:

  1. Right upper abdominal pain referable to the epigastrium, right chest or right shoulder
  2. Fever
  3. Malaise
  4. Sweats
  5. Cough
  6. Hiccups
  7. Anorexia
  8. Weight loss
  9. Jaundice (uncommon)
  10. Concurrent diarrhoea (less than one-third of patients)

Signs of amoebic liver abscess

The signs of amoebic liver abscess include the following:

  1. Large tender liver
  2. Tenderness and/or bulging at right intercostal spaces
  3. Jaundice
  4. Dullness to percussion on the right lower chest zones with basal crepitations
  5. Amoebic empyema following extension into the chest cavity
  6. Peritonitis (uncommon)

Investigations

  • Abdominal ultrasound
  • Chest X-ray
  • FBC
  • ESR
  • Stool examination
  • Abdominal CT scan Serology (amoebic antibodies)

Treatment for amoebic liver abscess

Objectives

The treatment objectives of amoebic LA are:

  1. To eradicate Entamoeba histolytica infection
  2. To prevent further destruction of liver tissue
  3. To prevent further complications (e.g. rupture of abscess into pleural, pericardial or peritoneal space)

Non-pharmacological treatment

Therapeutic aspiration may be required in patients with poor response to therapy

Pharmacological treatment

1st Line Treatment

Evidence Rating: [A]
Metronidazole, oral,
Adults: 800 mg 8 hourly for 10 days (tissue agent)
Children 15 mg/kg 8 hourly for 10 days (tissue agent)

Then

Diloxanide furoate, oral,
Adults: 500 mg 8 hourly for 10 days (luminal agent)
Children 6-8 mg/kg 8 hourly for 10 days (luminal agent)

2nd Line Treatment

Evidence Rating: [A]
Tinidazole, oral,
Adults: 2 g once daily for 5 days (tissue agent)
Children

  • > 3 years; 50 mg/kg (max. 2 g) once daily for 5 days (tissue agent)

Then

Paromomycin, oral,
Adults: 8-10 mg/kg 8 hourly for 7 days (luminal agent)
Children: 8-10 mg/kg 8 hourly for 7 days (luminal agent)

Referral Criteria

Patients with abscesses that are large or not responding to treatment will need to be referred to a specialist.