What Is an Amebic Liver Abscess?

Amoebic liver abscess is formed because the lysed histolytic amoeba trophozoites enter the liver through the bloodstream from the intestinal lesions, causing necrosis of the liver. It is a complication of amoebic colitis, but it can also be free of amoeba colitis. And exist alone. The main clinical manifestations are long-term fever, right upper quadrant or lower right chest pain, systemic exhaustion, tenderness of liver enlargement, and leukopenia, etc., and it is easy to cause chest complications. The ileocecal area and ascending colon are the most common sites of amoeba colitis, where the protozoa can return to the right lobe of the liver with the superior mesenteric vein, so the majority of abscesses in the right lobe of the liver.

Basic Information

Visiting department: Gastroenterology
Common causes: Causes of amoebic trophozoites from the intestinal lesions to enter the liver through blood flow

Common symptoms: Long-term fever, right upper quadrant or lower right chest pain, systemic exhaustion, tenderness of liver enlargement, white blood cells, etc.

Causes of amoebic liver abscess

Amoeba has two diseased strains, namely, Spane amoeba and Hemolytic histolytica. Amoeba Histolytica is pathogenic and is the pathogen causing amoebic liver abscess. There are two phases of trophozoites and cysts in the amoeba. The trophozoites used to divide them into small trophozoites and large trophozoites. The former is parasitic in the intestinal cavity and is called intestinal commensal trophozoite. In some factors, Under the influence, it invades the intestinal wall, swallows red blood cells and transforms into a large trophozoite, called a tissue-type trophozoite, which is the pathogenic form of amoebic liver abscess.

Clinical manifestations of amoebic liver abscess

It is related to the course of the disease, the size and location of the abscess, and the presence or absence of complications. Most of them slowly rise, with irregular fever, night sweats and other symptoms. Fever is mostly intermittent or relaxation type. When there are complications, the body temperature often reaches above 39 ° C and can show bimodal fever. Most of the body temperature rose in the afternoon, peaked in the evening, night sweats accompanied by night sweats, fever and chills often associated with bacterial infections. There are often symptoms of loss of appetite, bloating, nausea, vomiting, diarrhea, and dysentery. Hepatic pain is an important symptom of the disease. It presents persistent dull pain, which increases with deep breathing and changes in body position. The pain at night is often more pronounced. Abscesses on the top of the right lobe can stimulate the right diaphragm, causing right shoulder pain or compression of the right lower lung and causing signs of pneumonia or pleurisy, such as shortness of breath, cough, and compression of the bottom of the right lung causing signs of pneumonia or pleurisy. Bottom smell and wet rales, pleural friction sounds on the abdomen. Abscesses can cause right upper quadrant pain and right lower back pain when located in the lower part of the liver. In some patients, the right lower chest or right upper abdomen is full, or the lumps and bumps are accompanied by tenderness, and there are few left lobe liver abscesses. The patient had mid-upper or left upper quadrant pain, radiating to the left shoulder, hepatic abscess under the xiphoid process, or full mid- and left-upper abdomen, tenderness, muscle tension, and pain in the liver area. The liver is often diffusely swollen, with marked localized tenderness and throbbing pain at the site of the lesion. The lower edge of the liver is obtuse, full, and solid. Some patients have a limited sense of fluctuation in the liver area. Jaundice is rare and mild, and the incidence of jaundice is higher in multiple abscesses.

Chronic diseases are in a state of exhaustion, weight loss, anemia, nutritional edema, and fever are not obvious. Some advanced patients have hepatomegaly, firm quality, local bulge, and are prone to be mistaken for liver cancer.

Amoebic liver abscess examination

Blood test

The total number of white blood cells in the acute phase increased moderately, about 80% of neutrophils, and more when there were secondary infections. When the disease course is longer, most of the white blood cell counts are close to normal or decreased, anemia is more obvious, and erythrocyte sedimentation increases faster.

2. stool test

A few patients can detect histolytic amoeba.

3. Liver function test

Alkaline phosphatase increase is most common, cholesterol and albumin are mostly reduced, and other indicators are basically normal.

4. Serology

The antibody positive rate can reach more than 90%. Negative patients can basically rule out the disease.

5. Liver imaging

B-mode ultrasound imaging has high sensitivity, but it is difficult to distinguish from other fluid lesions, and dynamic observation is needed. The location of the abscess shows a liquid level that is basically the same as the size of the abscess or for puncture or surgical drainage positioning. Repeated exploration can observe the progress of the abscess cavity.

CT, hepatic arteriography, radionuclide liver scan, and magnetic resonance can all show intrahepatic space-occupying lesions, which is helpful to identify amoebic liver disease, liver cancer, and liver cysts. Among them, CT is particularly convenient. On the CT, it appears as a low-density focus of round or oval shape. The edges are not clear. The wall of the abscess is enhanced after enhancement. If there is gas in it, it is of great value for diagnosis.

X-ray examinations usually include elevation of the right diaphragmatic muscle, restricted movement, pleural response or effusion, and cloud-like shadows on the lung base. In the left lobe liver abscess, the gastrointestinal barium meal can be seen through compression of the gastric cramp or duodenum displacement. Lateral radiographs show that the right medial anterior medial bulge causes the palate angle or anterior angle to disappear. Occasionally, irregular light-transmitting fluid-air shadows in the liver area are seen on plain films, which is quite characteristic.

Diagnosis of amoebic liver abscess

The basic points of clinical diagnosis of liver enlargement are: right upper abdominal pain, fever, liver enlargement and tenderness; X-ray examination of right diaphragmatic muscle elevation and weakened movement; ultrasound examination shows the level of fluid in the liver area. If typical pus is obtained by liver puncture, or amoeba trophozoites are found in the pus, or if it has a good effect on the specific anti-amebia drug treatment, then amoebic liver abscess can be confirmed.

Differential diagnosis of amoebic liver abscess

This disease should be distinguished from the following:

Primary liver cancer

The clinical manifestations of fever, weight loss, right upper quadrant pain, and hepatomegaly resemble amoebic liver abscesses, but the latter often has a higher degree of fever, hepatic pain is more pronounced, and the texture of the cancerous liver is harder, with nodules. The determination of alpha-fetoprotein, B-mode ultrasound, abdominal CT, radionuclide liver area scanning, selective hepatic angiography, and magnetic resonance imaging can be clearly diagnosed. Liver aspiration and anti-amoeba drug treatment tests can help identify.

2. Bacterial liver abscess

It often occurs after sepsis or abdominal purulent diseases, and it has an acute onset and significant symptoms of toxic blood, such as chills, high fever, shock, and jaundice. The swelling is not significant, and the local tenderness is also mild. Generally there is no local bulge, and the abscesses are small and many. There is less pus, yellowish white, and positive results can be obtained by bacterial culture. Pathological examination of the liver tissue shows purulent lesions. Leukocyte counts, especially neutrophils, increased significantly, and positive results were obtained from bacterial culture. Antibiotic treatment is effective and easy to relapse.

3. Schistosomiasis

In the endemic area of schistosomiasis, liver amoebiasis is easily misdiagnosed as acute schistosomiasis. Both have fever, diarrhea, and hepatomegaly, but the latter has milder liver pain, more pronounced splenomegaly, and significantly increased eosinophils in the blood image. Sigmoidoscopy and worm egg soluble antigen testing can help identify .

4. Cholecystitis

Sudden onset of symptoms, paroxysmal aggravation of right upper quadrant pain, and often a history of recurrent attacks. Jaundice is more common and deeper, hepatomegaly is not significant, and tenderness in the gallbladder area is obvious. It can be identified by cholecystography and duodenal drainage.

5. Liver cyst

It is usually difficult to identify, but patients with chronic amoebic liver abscesses without obvious clinical manifestations of inflammation, or those with liver cysts and infections also need to be carefully identified. Ultrasound imaging and the characteristics of the pus obtained from the puncture can help distinguish.

Amoebic liver abscess complications

The main complication was secondary bacterial infection and abscess breakthrough to surrounding tissues. During the secondary bacterial infection, chills and high fever were more obvious, toxemia worsened, the total number of white blood cells and neutrophils were significantly increased, the pus was yellow-green or odorous, and a large number of pus cells were found on the microscope, but the bacterial culture was positive. not tall. Amoebic liver abscesses penetrate to surrounding organs, such as through the diaphragm to form empyema or lung abscesses, to the bronchus to cause pleural-pulmonary-bronchial fistula, to the pericardium or abdominal cavity causing pericarditis or peritonitis, and to the stomach , Large intestine, inferior vena cava, common bile duct, right renal pelvis, etc., causing amoebiasis of various organs. Except for puncturing the gastrointestinal tract or forming a liver-bronchial fistula, the prognosis is mostly poor.

Amoebic liver abscess treatment

Medical treatment

(1) Anti-amoeba treatment The main choice is to kill ameba in tissues, supplemented by intestinal ameba to cure. At present, metronidazole is mostly preferred, and the cure rate is very high. In patients without complications, the clinical conditions such as liver pain and fever were significantly improved within 72 hours after taking the medicine. The body temperature subsided within 6 to 9 days. Hepatomegaly, tenderness, and increased white blood cell count recovered in about 2 weeks after treatment. The pus cavity absorption was delayed. To about 4 months.

(2) Liver puncture and drainage Early use of effective drug treatment, many liver abscesses are no longer necessary for puncture. For 5 to 7 days of appropriate drug treatment, the clinical conditions did not improve significantly, or local liver bulging was significant, tenderness was obvious, abscess diameter> 6cm, and those at risk of puncture were treated with puncture drainage. The puncture is best performed after 2 to 4 days of anti-amoeba medication. The puncture site is usually selected in the 8th or 9th intercostal space of the right anterior axillary line, or the 9th or 10th intercostal space or liver area in the right middle axillary line. Where it is obvious, it is best to perform it under the position of ultrasonic exploration. The number of punctures is silent as the disease requires, and pus should be pumped as much as possible for each puncture. Those with pus volume of more than 200ml often need to repeat the aspiration after 3 to 5 days. Large pus cavities can accelerate recovery by suction. In recent years, the interventional therapy has been guided by a guide needle for continuous closed drainage, which can avoid the disadvantages of repeated puncture and secondary infection, and it can be used by those who have the conditions.

(3) Antibiotic treatment When there is mixed infection, use appropriate antibiotics for systemic application depending on the type of bacteria.

2. Surgical treatment

Hepatic abscesses need to be drained by surgery 8cm), puncture is easy to hurt nearby organs; abscesses penetrate into the abdominal cavity or adjacent internal organs and have poor drainage; there are secondary bacterial infections in the abscess, which can not be controlled by medication; An abscess that makes puncture drainage difficult or unsuccessful; liver abscess in the left lobe, easy to puncture the pericardium, puncture easy to contaminate the abdominal cavity, surgery should also be considered.

The cure standard for liver abscess is not consistent, and the clinical cure is usually based on the disappearance of symptoms and signs. Most of the filling defects of liver abscesses are completely absorbed within 6 months, and a few can last up to 1 year. Hepatic cysts can remain in those with larger lesions. ESR can also be used as a reference indicator.

Amoebic liver abscess prevention

The disease mainly enters the intestinal tract of the body through the contamination of water, food, vegetables, etc. by amoebas, and then invades the liver and causes abscesses. Therefore, the key to preventing this disease is to pay attention to food hygiene and prevent the disease from entering the mouth.