A Guide to Liver Abscesses
An untreated liver abscess can burst and cause the infection to spread. Serious complications include sepsis, a life threatening bacterial blood infection.
Explore this article to learn about the liver, including liver abscess causes, symptoms, and treatments.
A liver abscess is a pocket of pus that develops in the liver due to an infection. Liver abscesses fall into three categories based on the underlying cause: bacterial infection, parasitic infection, or injury to the liver.
- Pyogenic liver abscess: Bacterial infection causes this abscess. “Pyogenic” means producing pus. Infections spread directly from nearby structures, such as the bile-draining tubes, or from the appendix or intestines. The bloodstream may carry infection from more distant parts of the body.
- Amebic liver abscess: The parasite Entamoeba histolytica causes this abscess. E. histolytica causes amebic dysentery, an intestinal infection. From the intestines, the parasite can travel through the bloodstream to the liver. In rare cases, other organisms or fungi can cause a liver abscess.
- Injury-induced liver abscess: Surgery, a diagnostic procedure, or trauma to the liver may cause an abscess.
A liver abscess can quickly advance to a serious infection. Without treatment, a liver abscess can rupture and spread the infection to neighboring organs and structures. This can lead to serious, potentially life threatening complications and infections.
The liver is an organ that assists in the digestive process. It carries out essential functions, including:
- storing nutrients
- removing waste from the blood
- filtering food, drugs, and alcohol from the blood
- producing bile, which helps to digest food in the intestines
Because some of its primary functions are to clean and filter the blood, the liver is prone to infections.
Liver abscess symptoms vary and commonly include multiple symptoms. At times, any of these symptoms can be severe:
- abdominal pain, especially in the upper right portion of the abdomen
- dark urine
- difficulty breathing
- fever or chills
- malaise or lethargy
- nausea with or without vomiting
- right shoulder pain
- unexplained weight loss
Serious symptoms that might indicate a life threatening condition
In some cases, a liver abscess can be life threatening. An untreated liver abscess that ruptures can cause a blood infection called sepsis.
Seek immediate medical care (call 911) for these symptoms that might indicate a life threatening condition:
- change in mental status, such as confusion, delirium, fainting, or unresponsiveness
- fever higher than 101°F (38°C)
- jerky movements
- tachycardia, a heart rate of more than 100 beats per minute
- respiratory problems, such as shortness of breath, difficulty breathing, wheezing, or rapid breathing
- severe pain
Anyone can get a liver abscess. Liver abscess causes include bacterial infection, parasitic infection, and liver injury.
Infectious causes of a liver abscess
The following infectious causes may result in a liver abscess:
- bacterial infection in the bile-draining tubes
- bacterial infections in the abdomen associated with appendicitis, diverticulitis, or perforated bowel
- bloodstream infections
- E. histolytica infections
- parasites or fungus, rarely
Traumatic causes of a liver abscess
Trauma to the liver may occur during a surgical or diagnostic procedure, such as an endoscopy, resulting in a liver abscess. Other trauma to the abdomen that introduces an infection may cause a liver abscess.
A number of factors increase the risk of developing a liver abscess. Not all people with risk factors will get a liver abscess.
Risk factors for liver abscess include:
- middle age, people 40–60 years of age are at increased risk for nontraumatic causes
- alcohol use disorder
- a compromised immune system due to conditions such as AIDS, taking corticosteroids, organ transplants, or cancer and cancer treatments
- gastrointestinal conditions such as diverticulitis, cholecystitis, and Crohn’s disease
- a diet low in nutritious foods
- recent abdominal surgery
- recent endoscopy of the bile-draining tubes
- use of proton pump inhibitor medications
- travel to regions where amebic infections are common
Reducing your risk of developing a liver abscess
It is not always possible to avoid a liver abscess. However, you may be able to lower your risk of liver abscess by:
- avoiding contaminated food or water
- limiting travel in regions where amebic infections are common
- reducing alcohol intake
- managing underlying health conditions that can put you at risk for developing liver abscesses
To diagnose a liver abscess, your doctor will take a medical history, perform an exam, and possibly order testing.
Certain risk factors promote liver abscesses. Your doctor will ask questions about your symptoms, health conditions, and recent travel.
Tests may include:
- complete blood count
- liver function blood test
- blood cultures to check for bacterial infections
If your doctor suspects an amebic infection, other tests may include:
- stool sample analysis
- serology, a blood serum analysis, to look for E. histolytica antibodies that can indicate a present or previous amebic infection
Imaging tests may include:
For an amebic liver abscess, treatment focuses on clearing the infection. Additional medication is then necessary to kill any parasites remaining in the intestines.
Surgical treatment for a liver abscess
In some cases, doctors may treat the abscess by surgically draining it. This procedure involves inserting a needle or small tube into the abdomen and liver.
Oral antibiotics for a liver abscess
Many different antibiotics are available to treat a liver abscess. The nature of the infecting organism and the seriousness of the infection determine the choice of antibiotics.
- aminoglycosides, such as amikacin (Amikin) or gentamicin (Garamycin)
- combination piperacillin-tazobactam (Zosyn)
- metronidazole (Flagyl)
Complications of untreated or uncontrolled liver abscess can be serious, even life threatening, in some cases. You can help minimize your risk of serious complications by following the treatment plan that you and your doctor design specifically for you.
Rupture of the liver abscess can cause these complications:
- acute respiratory distress
- empyema, pus accumulation in the chest
- encephalopathy, a decline in brain function, from infection in this case
- endocarditis, inflammation of the heart’s inner lining and valves
- kidney failure
- liver failure
- peritonitis, inflammation of the tissue that lines the abdomen
- pleural effusion, accumulation of fluid around the lungs
- sepsis, a life threatening blood infection
- spread of infection
Here are some other common questions people ask about liver abscesses.
How common are liver abscesses?
According to the National Institutes of Health (NIH), only about 2.3 people per every 100,000 will develop a liver abscess.
What is the difference between a pyogenic and an amebic liver abscess?
A bacterial infection causes a pyogenic abscess. Parasitic infection from E. histolytica causes an amebic liver abscess.
Where is E. histolytica found?
The parasite E. histolytica is more common in areas with less sanitary conditions. Countries with higher infection rates include Mexico, Central America, South America, India, and Africa, according to the NIH.
A liver abscess is a serious condition caused by an infection that accumulates in a cyst in the liver. The most common causes of liver abscess are bacterial or parasitic infections. Trauma or injury to the liver can also result in a liver abscess.
Treatments for a liver abscess commonly include a course of antibiotics. In serious cases, doctors may also recommend surgically draining the abscess. In the case of a parasitic infection, an additional medication to kill the parasite is necessary to avoid future infections.
If not treated quickly and properly, the cyst can rupture, leading to a potentially life threatening condition.
Because a liver abscess can quickly turn into a more serious infection, it is important to know the signs and symptoms. Contact your doctor promptly if you experience even mild symptoms of a liver abscess.