Liver cyst and liver abscess

The liver cyst is a cavity filled with fluid or solid material, enclosed in a capsule and surrounded by normal liver tissue.

Usually, a liver cyst is not of “parasitic origin”, to put it simply.

Liver cysts can be of the following type:

1. simple cysts;
2. multiple cysts that occur in polycystic liver disease (cystic liver);
3. parasitic or hydatid cysts (by echinococcus);
4. tumor cysts;
5. Abscesses.

Rarely, a cyst can be a liver tumor that secretes fluid.
In this case, these are called cystadenoma (if benign) or cystadenocarcinoma (if malignant).
Liver cysts can be of different sizes, from a few millimeters to large formations that can reach 20 cm.
Most cysts found are less than 2 cm long.
Usually, liver cysts cause no symptoms and are discovered only by chance when an echography or CT scan is performed.

Causes of liver cysts

The exact cause of simple liver cysts is unknown. Some experts believe that they may be present from birth, while others assume that they are caused by certain diseases, including:

1. Caroli syndrome – characterized by recurrent bacterial infections of the bile duct, stone formation and dilation of the intrahepatic bile ducts.
2. Congenital liver fibrosis (existing from birth) – a rare hereditary disease, characterized by an irregular shape of the bile ducts and by the formation of fibrous tissue containing multiple cysts.
   Congenital liver fibrosis is often associated with impaired renal function.
3. Choledochus cysts – congenital anomalies of the bile ducts.

In rare cases, the liver cysts may indicate a serious disease such as a polycystic liver (congenital disease associated with many cysts of different sizes), echinococcosis (parasitic infection) or liver cancer.

Simple or serous liver cysts

The simple cysts (benign) are probably congenital.
They are surrounded by biliary epithelium, but do not contain bile.
If the fluid is aspirated from the inside, it is immediately renewed because the body continues to produce it.

Symptoms of simple cysts
The simple liver cysts are usually asymptomatic (do not cause discomfort).
If they are of considerable size, they can cause pain in the right side and a swollen abdomen.
A correct diagnosis is important, as the patient’s symptoms are usually caused by other diseases and so there is a risk that unnecessary interventions will be made.

If the liver parenchyma cysts (meaning that they are found inside the hepatocytes) are very large, they can be palpated in the abdomen.
Tearing or twisting of the cysts and jaundice caused by narrowing of the bile ducts are rare.

Diagnosis: Echography and CT are possible methods of examination by which the cysts are revealed.
Functional tests of the liver can give slightly abnormal results.

Therapy: Is only required if symptoms occur, i.e. infection, rupture or pressure on other organs or blood vessels.

Many patients want the fluid to be sucked out of the cyst, but unfortunately the cyst fills up again after a short time, so this is not an effective form of therapy.

Surgical removal of the liver cysts can be performed in laparoscopy, which involves the removal of a part of the wall that extends on the surface of the liver.
In this case, the cyst fluid can be drained in the abdominal cavity.

Prognosis: The surgical intervention has a cure rate of 90%.

Neoplastic liver cysts

Liver tumors with necrosis visualized by apparatus (for example, magnetic resonance imaging) are often wrongly diagnosed as liver cysts.
True intrahepatic neoplastic cysts are rare.
The cause of cystadenomas and cystadenocarcinomas is unknown, but they may represent embryonic abnormal tissue proliferation of the biliary epithelium or gallbladder.
These cystic tumors are covered by cubic (or columnar) cells of the biliary type and surrounded by stroma (supportive connective tissue), similar to the ovaries.
Cystadenoma is a precancerous lesion that can undergo a neoplastic transformation into a cystadenocarcinoma.

Diagnosis: The liver function tests may give normal values.
CT, magnetic resonance imaging and ultrasound show the abnormal formation, as well as the presence of perfused internal partitions (septa).

Therapy: It consists in the resection of the liver. Even if a complete resection of the tumor and the surrounding liver portion occurs, cystadenocarcinoma can recur.

Hydatid cysts

The hydatid cyst is caused by the parasite Echinococci granulosus.
This parasite is a tapeworm that occurs worldwide, but mainly in sheep and cattle breeding.
The adult tapeworm lives in the digestive tract of carnivores such as dogs or wolves.
The eggs are released through the stool and ingested randomly by intermediate hosts such as sheep, cattle or humans.
The egg larvae penetrate the intestinal wall into the mesenteric vessels of the intermediate host and thus enter the liver.
In the liver, the larvae grow and transform into hydatid cysts.
The hydatid cyst develops an outer layer of inflammatory tissue and an inner germ membrane that produces daughter cysts.
When carnivores swallow the liver of the intermediate host, the daughter cysts are released into the small intestine and develop into adult worms. Thus, they complete the life cycle of the tapeworm.

Symptoms: The hydatid cyst can be asymptomatic (up to 10 or 20 years) or occur with pain in the right side.
Large cysts can burst in the bile ducts (causing jaundice or cholangitis), in the chest or in the abdominal cavity (here this can lead to anaphylactic shock).
Secondary infections and liver abscesses can arise from the bursting of the hydatid cyst. The hydatid cysts can also form in the lungs and other organs.

Diagnosis: Blood tests may reveal an increased concentration of eosinophilic white blood cells.
Antibodies against echinococcus are positive in 80% of patients.
Ultrasound, CT and MRI show the classic appearance with a daughter cyst inside the main cavity with thickened walls.

Therapy: It is necessary to prevent complications caused by the growth of cysts and their rupture.

Polycystic liver disease

Polycystic liver disease rarely occurs in childhood.
These cysts are found in both adolescents and adults.
They present as part of a congenital disorder associated with polycystic kidneys.
Women are affected more often, the extent and number of cysts correlate with estrogen levels.
With polycystic liver disease, there may be consequences such as liver enlargement and liver fibrosis, hepatic insufficiency and portal hypertension.
Complications such as rupture, bleeding and infection are rare.
However, these patients have abdominal pain when the cysts become larger.

Diagnosis: Here an examination of the kidneys and kidney function is required. Liver function tests may show abnormal values, but hepatic insufficiency is rare.
Echography and CT show multiple liver cysts.
In echography, the liquid material inside is displayed as an anechoic zone, i.e. black.
The ultrasound examination can also be performed during pregnancy.

Therapy: Is required only if symptoms occur.
Surgical options include removal or resection of the liver.
However, the recurrence of symptoms and the emergence of new cysts are common.
Rarely, liver transplantation is performed.

Prognosis: Some small studies have shown success rates without a recurrence between 40 and 78%.

Contraindications
Contraindications to the treatment of symptomatic liver cysts are associated diseases that increase the risks of surgery, which include:

1. Compensated heart failure
2. Hepatic insufficiency with portal hypertension
3. Ascites

Therapy for liver cysts

One should follow the basic nutritional principles for a healthy liver.
For example, if you have a simple liver cyst, you should try to limit dairy products such as butter, cheese, milk and cream.
Any form of margarine and similar products should be avoided.
Fried and fatty foods should be avoided.
Eat less chicken and turkey, which contain artificial growth hormones, antibiotics and steroids and can put a strain on the liver.
Avoid all alcoholic beverages.
Drink 2 liters of water daily.
Artificial sweeteners should be avoided. You can use natural plant-based sweeteners instead to avoid sugar.

Liver abscess

Liver abscesses are caused by bacteria, fungi or parasites.
Amoebic dysentery leads to the formation of amoebic cysts.
The purulent liver abscess is an accumulation of pus caused by bacteria (especially E. coli).
In developed countries, purulent liver abscesses are the most common, but amoebas are the main cause worldwide.
Liver abscesses manifest themselves with leukocytosis, fever and abdominal pain.
The clinical history is important for the identification of concomitant diseases.
Patients with amoebic dysentery may suffer from diarrhea and weight loss, although in some cases this disease is asymptomatic.

Pus abscesses often occur together with cholangitis, sepsis or abdominal infection.
Rarely, the abscesses burst and the patients then suffer peritonitis.

Features of purulent liver abscesses
The abscesses can occur singly or multiple times. The right lobe of the liver is affected twice more often than the left, in 5% of cases they occur on both sides.
In most cases, they occur secondarily as a result of an infection in the abdomen (cholangitis, diverticulitis, appendicitis, Crohn’s disease or peptic perforated ulcer).
The infection can also occur in the hospital (secondary after liver biopsy or after a stent in case of bile duct occlusion).
Bacterial endocarditis and tooth infection are other causes.
In 15% of cases, there are no known causes.
They are more common in immunosuppressed patients.
15% of adults with a liver abscess have diabetes.
Cirrhosis of the liver is a significant risk factor.
Liver abscess is a complication of scarring of the umbilical vein in newborns. In children and adolescents, the immune system may be impaired or trauma may be present.

Symptoms of liver abscess

• Chest pain (bottom right)
• Clay-coloured chair
• Dark urine
• Fever, chills
• Loss of appetite
• Nausea, vomiting
• Right-sided flank pain in the upper area (common) or in the entire abdomen (less common)
• Unexplained weight loss
• Weakness
• Yellow skin (jaundice)

Diagnosis of liver abscess

In pus-forming liver abscesses, up to 50% have a positive blood culture, with high levels of white blood cells and alkaline phosphatases.
Hyperbilirubinaemia with or without jaundice occurs in less than 50% of patients.

The imaging techniques for diagnosis are CT, magnetic resonance imaging and ultrasound.

Percutaneous drainage guided by ultrasound or CT (with a needle inserted from the outside, without incisions) should be considered for confirmation or culture.

Differential diagnosis

• Liver metastases
• Hepatocellular carcinoma
• Biliary diseases including cholecystitis
• Bacterial pneumonia
• Gastritis

Therapy for liver abscess

Purulent liver abscess
Broad-spectrum antibiotics should be administered before the results of a culture arrive.
Application of penicillin, an aminoglycoside and metronidazole. A third-generation cephalosporin can be given to elderly patients or those whose kidney function is impaired.

Amoeba abscess of the liver
Metronidazole is the preferred therapy. 95% of patients with an amoeba abscess of the liver recover from this simple medical treatment

Drainage
Most patients with a purulent liver abscess or with very large amoeba abscesses can not be cured with antibiotics. If the medications don’t help, ultrasound or CT-guided drainage may be performed.

Prognosis and recovery times

Purulent liver abscess: Early diagnosis and treatment with antibiotics improve outcome, but the mortality rate is still 5-30%.
Factors that affect the prognosis include:

• Shock
• consumption coagulopathy,
• Immunodeficiency
• Diabetes
• associated cancer development,
• ineffective surgical drainage.

Amoeba abscess of the liver: Since the introduction of early detection and effective therapy, the mortality rate has fallen to one to three percent.

• Infectious and primary sclerosing cholangitis
• Liver cancer: treatment and cure
• Hepatitis C: therapy and medication