Causes of a liver abscess | Liver abscess

Causes of a liver abscess

In most cases, liver abscesses do not occur alone, but are the result of an inflammation in another organ. These liver abscesses are called secondary liver abscesses.One cause of this can be an inflammation of the bile duct (cholangitis), which spreads to the liver and then leads to an abscess. Another way in which pathogens can enter the liver and lead to an abscess is through the bloodstream.

Pathogens are mostly bacteria, but fungi and parasites are also possible. In the case of primary liver abscesses, the cause lies directly in the liver. Parasites, such as the fox tapeworm or the dog tapeworm, attack the liver directly and lead to abscesses there.

However, these are transmitted by animals and are only rarely the cause. Another pathogen is the amoeba Entamoeba histolytica. It leads to amoebiasis, which is only common in the subtropics and tropics.

In some forms of the disease, the liver may be affected. In addition, inflammation can spread from the gallbladder or bile duct to the liver, where it can lead to liver abscesses. This is the most common cause.

Injury to the liver through an accident is also a possible cause. Due to the spatial narrowness of the gallbladder to the liver, it can easily be injured. This injury can lead to inflammation and the formation of an abscess. However, other causes can also lead to an infection after gall bladder surgery, resulting in liver abscesses. Another possibility is, for example, a leaking bile duct after the operation, because the bile duct was injured, a bile duct fistula (an extra duct into the abdominal cavity) forms after the operation or the blind end of the bile duct was not sealed tightly.

Symptoms of a liver abscess

Chills and fever, increased inflammation values in the laboratory, painful pressure in the right abdomen. Nausea, vomiting and diarrhoea may also occur. In some cases a yellow skin color (icterus) and anemia (anemia) may occur.

Since the liver abscess can be caused by various pathogens, therapeutic measures differ depending on the type of abscess. Accordingly, a therapy can only be planned once it is clear what has caused it. A differentiation is not always easy, however.

The combination of the patient’s clinical symptoms, the results of the sonography (ultrasound) and possibly an additional computer tomography usually points in one direction. In some cases, it can be assumed that it is a pyogenic (purulent) abscess caused by bacteria that have spread to the liver via the portal vein (vessels leading to the liver), for example in the context of appendicitis or inflammation of the bile ducts (cholangitis). Then the following therapy scheme is followed: The abscess is punctured and drained.

First, an ultrasound of the liver is used to determine where puncture is appropriate. This site is then marked on the skin. This is usually followed by an injection of a local anesthetic to make the actual puncture as painless as possible.

After the anaesthetic has briefly taken effect, a fine needle is inserted percutaneously through the skin at the marked site under sterile conditions, with which the liver abscess is punctured. The contents of the abscess are then sucked out (aspirated and drained, so to speak). At the same time, antibiotic therapy is started to eliminate the pathogen – usually over several weeks.

If the percutaneous puncture of the liver abscess is not successful, a small operation is indicated, in which a tube is inserted into the abscess cavity to ensure that its contents can drain continuously. This is called drainage. The antibiotic therapy should be effective against aerobic and anaerobic bacteria – unless the pathogens are already known and can be treated specifically.

The most common pathogens of a pyogenic liver abscess are Escherichia coli (E. coli) or bacteria from the group of Klebsiellae. A combination of an antibiotic from the group of cephalosporins (for example cefotaxime) or acylaminopenicillins (for example mezlocillin) in combination with metronidazole is often used for antibiotic treatment. A second form of liver abscess is caused by amoebae (Entamoeba histolytica).

In this case, usually no puncture and drainage of the abscess is performed, but antibiotic treatment with metronidazole is started for about ten days. Regardless of the type of abscess, the patient should continue to be monitored after the start of therapy. Persistence of symptoms such as recurrent (intermittent) fever, malaise, and right-sided pain in the upper abdomen indicate that the therapy is not working.Sonographic controls can also give a rough indication of whether the therapy is helping, as can repeated blood samples for laboratory control.

The therapy of liver abscesses depends on the pathogen that caused the disease. In general, the disease is initially treated conservatively, i.e. with medication. Only if conservative measures are not sufficient, surgical removal of the abscess is resorted to.

Liver abscesses caused by amoebas are classically treated with the antibiotic metronidazole. The therapy is initially administered via the patient’s vein. The dosage is 3x10mg per day and kilogram of the patient’s body weight and lasts for 10 days.

The maximum dose is 3x800mg per day. However, since metronidazole is not sufficiently effective against the pathogens that are still in the intestine, the antibiotic paromomycin is still used afterwards. The dosage is 3x500mg per day for 9-10 days.

Liver abscesses, which are caused by other pathogens, for example by Enterobakterien, are likewise treated with antibiotics. Metronidazole is also frequently effective, additionally Ceftriaxon can be used. In addition to the drugs, the abscess cavity can also be punctured.

With amoeba abscesses this is only done in exceptional cases, with bacterial abscesses regularly. For this purpose, the liver abscess is punctured through the skin and emptied and rinsed through a tube. If the conservative measures are not sufficient to get the disease under control, surgical repair of the abscess must be considered.

This is more often done even in the presence of several abscess foci. The abscesses can either be removed individually during surgery, but partial resection of the liver may also be necessary. The affected part of the liver is completely removed. This is usually not a problem after the operation, since the liver can grow back to its original size if sufficient residual tissue is available.