Biliary ascariasis in children

　　First, Etiology

　　1. Intestinal dysfunction: such as fever and diarrhea, the environment inside the intestinal cavity changes, promoting the enhancement of ascaris activity.

　　2. Inadequate anthelmintic drugs, stimulating the activity of ascaris to increase.

　　3. Medications or diet change the acidity and alkalinity of the intestinal lumen, ascaris prefers alkaline and dislikes acid. Low acid can promote the retrograde movement of ascaris. Children often have ascaris in the intestinal tract, but generally do not show symptoms. When there is hunger, high fever, postoperative gastrointestinal surgery, or improper dosage of anthelmintic drugs, the normal environment of the body is changed. Gastrointestinal dysfunction, internal environment change, plus the habit of ascaris drilling, ascaris can窜 to the duodenum. When the lower end of the bile duct Oddi sphincter is relaxed, functionally incomplete, bile duct dilated, and alkaline-loving ascaris is easy to drill into the bile duct. The mechanical stimulation of ascaris entering the bile duct causes the sphincter of the bile duct orifice to spasm and also brings bile duct infection.

　　Second, Pathogenesis

　　When the ascaris in the jejunum and ileum are stimulated, they can retrograde upwards to the stomach and duodenum; ascaris has the habit of drilling, when the Oddi sphincter relaxes, the ascaris enters the common bile duct, hepatic duct, and even the liver. After the ascaris enters the bile duct, the activity of the worm causes smooth muscle spasm, resulting in severe upper abdominal pain, and it can also cause bile duct infection due to the introduction of bacteria (mainly Escherichia coli), leading to liver abscess, which can seriously threaten the life of the child. Generally, the anterior half of a single ascaris enters the bile duct in children with biliary ascariasis, but there have also been reports of dozens of ascaris entering the common bile duct of a 4-year-old child. After the ascaris enters the bile duct, it can be automatically or passively excreted. There are three forms of ascaris exiting the bile duct:

　　1. Some segments of the worm are inside the bile duct, while the tail is still in the duodenum. Due to the compression of the bile duct spasm on the head, the tail strongly coils, causing the worm to exit the bile duct, which is the most common form;

　　2. The worm body enters the bile duct completely, and then the worm head turns and gradually comes out.

　　3. After the worm body dies or becomes paralyzed, part of it rots and is excreted with bile. However, if a large number of worms enter the bile duct or liver, it is not easy to exit.

　　The main complications of biliary ascariasis are as follows:

　　1. Biliary infection is mostly caused by Escherichia coli infection. The child has fever, the range of tenderness and tension in the right upper quadrant expands, and it persists, and sometimes a swollen and painful gallbladder can be felt under the right costal margin. The peripheral blood leukocyte count increases.

　　2. Biliary necrosis The paroxysmal severe pain decreases, but the tenderness area around the xiphoid process and the right lower quadrant expands, and abdominal muscle tension appears. If there is necrotic perforation, the range of muscle tension expands to the left upper quadrant or right lower quadrant, and biliary peritonitis occurs, with abdominal distension, muscle tension, and sometimes shock.

　　3. Hepatitis and liver abscess Ascariasis-induced hepatitis is characterized by liver enlargement, tenderness, high fever, increased white blood cells, and elevated transaminases. When abscesses form, the original paroxysmal severe pain disappears, and high fever, liver enlargement, and tenderness become the main symptoms. Liver ultrasound can detect solitary or multiple abscesses. Sometimes liver abscesses break into the subdiaphragmatic or pleural cavity, causing subdiaphragmatic abscess or empyema.

　　4. Pancreatitis Due to spasm of the bile duct outlet sphincter and ascaris blockage of the bile duct outlet, pancreatic juice reflux occurs, leading to acute pancreatitis, with tenderness and muscle tension in the left upper quadrant. Blood and urine amylase levels increase.

　　5. Liver and bile duct hemorrhage Ascaris ascending into the small bile ducts in the liver can cause liver or bile duct hemorrhage due to severe infection, which is excreted through the digestive tract, manifested as massive blood stools, vomiting coffee-like substances, or vomiting blood.

　　6. Cholelithiasis, the ascaris eggs or remnants in the bile duct can become the core, forming stones, which are sequelae of biliary ascariasis. It is rare in childhood.

　　There is a history of ascaris infection, the main symptoms are:

　　1. Abdominal pain and vomiting

　　The onset is acute, with a sudden severe pain in the right upper quadrant, unable to lie still, bending over and rolling, crying and sweating, pale or flushed face, poor spirit, loss of appetite, sometimes vomiting, occasionally vomiting ascaris, the pain during the interval is basically disappeared, or only slight pain in the upper abdomen, and the severe pain recurs after a short period of time. The onset and interval are irregular, and have a direct relationship with the activity of ascaris. When the ascaris dies in the bile duct or exits the bile duct, the pain gradually disappears.

　　2. Signs

　　Mainly there is a small area of tenderness in the right upper quadrant near the xiphoid process, and the tenderness point still exists when not in an attack. After complications occur, the range of tenderness increases and abdominal muscle tension appears, accompanied by fever, and a few patients may have jaundice.

　　Ascaris infection is a typical disease that enters through the mouth, so attention should be paid to dietary and living hygiene, improving living conditions, and correcting poor dietary and living habits are the fundamental measures for prevention:

　　1. Develop good hygiene habits of washing hands before and after meals, and do not eat unclean fruits and vegetables to avoid ascaris infection.

　　2. If there are symptoms of ascaris infection or the possibility of infection, timely deworming treatment should be carried out. When taking oral deworming drugs, it is necessary to pay attention to calculating the dosage according to age and weight (except for Enterocortis).

　　1. Feces examination: CanWorm eggs are found, and occult blood in feces can be positive.

　　2. Peripheral blood count:When complications occur, there are infectious blood pictures, increased leukocyte count and increased neutrophils.

　　3. Blood biochemistry test:When hepatitis occurs, the transaminase can increase.

　　4. Duodenal drainage examination:Worm eggs can be seen in the duodenal drainage fluid.

　　5. Barium meal or duodenal barium enema:Worm shadows can be seen in the duodenum.

　　6. Oral or intravenous cholangiography:Worm shadows can be found in all parts of the bile duct.

　　7. Retrograde cholangiography with duodenoscope:The most reliable diagnostic method is retrograde cholangiography or worm removal with fiberoptic duodenoscopy.

　　8. Ultrasound examination:It can show the expansion of the common bile duct and the shadow of the worm.

　　Diet should be regular and reasonable, that is, to take high-protein, high-vitamin foods as the mainstay. Choose plant or animal proteins with high nutritional value, such as milk, eggs, fish, lean meat, and various soy products. Various fresh vegetables and fruits are rich in vitamins and have high nutritional value.

　　The main measures for non-surgical therapy are to relieve spasm and pain

　　1. Traditional Chinese medicine therapy: The purpose is to tranquilize and expel worms.

　　2. Acupuncture therapy: Acupoint Xiangshen透Si Bai, using the twirling method. Renzhong uses the tremor method.

　　3. Antispasmodic analgesics: School-age children use pethidine (Duloxetine) 1-2mg/kg plus atropine 0.3-0.5mg intramuscularly. Oral aspirin has analgesic and antispasmodic effects, and acidic substances also have anthelmintic effects.

　　4. Antibiotics: Gentamicin, metronidazole (Gentian Violet), erythromycin, and others are used for prevention and control of infection.

　　5. Anthelmintics: Refer to the section on ascariasis or use oxygen to expel worms.

　　The surgical indications for the treatment of biliary ascariasis are:

　　1. Long-term (more than 1 week) severe pain that cannot be controlled by non-surgical therapy, expansion of muscle tension under the sternum, or jaundice.

　　2. Enlarged liver with tenderness, suspected liver abscess after ultrasonic examination.

　　3. Cholangiography shows that dead worms in the bile duct cannot be excreted for a long time. The surgical method is to incise the common bile duct to remove the worms and perform cholangiostomy.