Amebic liver abscess
Alternative Names
Hepatic amebiasis; Extraintestinal amebiasis; Abscess - amebic liver
Definition
Amebic liver abscess is a collection of pus in the liver in response to an intestinal parasite.
Causes
Amebic liver abscess is caused by Entamoeba histolytica. This is the same parasite that causes amebiasis, an intestinal infection that is also called amebic dysentery. After an infection has occurred, the parasite may be carried by the blood from the intestines to the liver.
The disease spreads from eating food or water that has been contaminated with feces (sometimes due to the use of human waste as fertilizer). It is also spread through person-to-person contact.
The infection occurs worldwide, but is most common in tropical areas where crowded living conditions and poor sanitation exist. Africa, Latin America, Southeast Asia, and India have significant health problems from this disease.
Risk factors for amebic liver abscess include:
- Alcoholism
- Cancer
- Immunosuppression including HIV infection
- Malnutrition
- Old age
- Pregnancy
- Recent travel to a tropical region
- Steroid use
Symptoms
There are usually no symptoms of intestinal infection. But persons with amebic liver abscess do have symptoms, including:
- Abdominal pain, particularly in the right, upper part of the abdomen; pain is intense, continuous or stabbing
- Cough
- Fever and chills
- Diarrhea (in only one-third of patients)
- General discomfort, uneasiness, or ill feeling (malaise)
- Hiccups that do not stop (rare)
- Jaundice
- Loss of appetite
- Sweating
- Weight loss
Exams and Tests
Tests that may be done include:
- Abdominal ultrasound
- Abdominal CT scan or MRI
- Complete blood count
- Liver abscess aspiration to check for bacterial infection in the liver abscess
- Liver scan
- Liver function tests
- Serology for amebiasis
- Stool testing for amebiasis
Treatment
Antibiotics such as metronidazole (Flagyl) or tinidazole (Tindamax) are the usual treatment for liver abscess. A medication such as paromomycin or diloxanide must also be taken to get rid of all the amoebas in the intestine and to prevent the disease from coming back. This treatment can usually be delayed until after the abscess has been treated.
In rare cases, the abscess may need to be drained to relieve some of the abdominal pain.
Outlook (Prognosis)
Without treatment, the abscess may break open (rupture) and spread into other organs, leading to death. People who are treated have a very high chance of a complete cure or only minor complications.
Possible Complications
The abscess may rupture into the abdominal cavity, the lining of the lungs, the lungs, or the sac around the heart. The infection can also spread to the brain.
When to Contact a Medical Professional
Call your health care provider if you develop symptoms of this disease, especially if you have recently traveled to an area where the disease is known to occur.
Prevention
When traveling in tropical countries with poor sanitation, drink purified water and do not eat uncooked vegetables or unpeeled fruit.
References
Donnelly JP, Blijlevens NMA, DePauw BE. Entamoeba species including amebiasis. In: Mandell GL, Bennett JE, Dolin R, eds. Mandell, Douglas, and Bennett's Principles and Practice of Infectious Disease. 7th ed. Philadelphia, Pa.: Elsevier Saunders; 2009:chap 273.
Reddy KR. Bacterial, parasitic, fungal, and granulomatous liver disease. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, Pa.: Elsevier Saunders; 2011:chap 154.