Congenital biliary atresia

　　Most congenital biliary tract anomalies are bile duct atresia and bile duct dilation, with only a small number showing stenosis changes.

　　Firstly, Congenital Biliary Atresia

　　The etiology of congenital bile duct atresia is not fully understood, and there are mainly two theories: congenital developmental malformation theory and viral infection theory. The obstructive jaundice caused by bile duct atresia can cause liver cell damage, and the liver becomes significantly enlarged, hard, and dark green or brownish-green due to cholestasis. If biliary obstruction cannot be resolved in time, liver dysfunction can develop into biliary cirrhosis, and the late stage is irreversible changes.

　　Second, congenital bile duct dilation

　　1. Congenital abnormality of the pancreaticobiliary junction: During the embryonic period, the common bile duct and the distal end of the pancreatic duct separate, with the common bile duct entering the pancreatic duct at a right angle, or the pancreatic duct merging into the bile duct above the ampulla, which makes pancreatic juice easily reflux into the bile duct, causing damage to the bile duct mucosa, fibrosis, and leading to cystic dilation of the common bile duct;

　　2. Congenital maldevelopment of the biliary tract: During embryogenesis, the primitive bile ducts proliferate into cord-like structures, which are then further vacuolized and connected. If there is excessive proliferation and vacuolization of a certain segment of bile duct epithelium, it can lead to a weak gallbladder wall and form an abnormal cystic dilation;

　　3. Genetic factors: The incidence of congenital bile duct dilation in females is significantly higher than in males, and some believe it is related to sex chromosomes.

　　Complications of congenital biliary tract anomalies in children are relatively serious. Children with congenital bile duct atresia often die within a year of birth due to infection, bleeding, liver failure, and hepatic coma. Children with congenital bile duct dilation may present with clinical manifestations of biliary cirrhosis and portal hypertension in the late stage.

　　Congenital biliary tract anomalies include bile duct atresia, bile duct stenosis, and bile duct dilation, among others, and their symptoms are manifested as follows:

　　Firstly, Congenital Biliary Atresia

　　1. Jaundice

　　Cholestatic jaundice is an outstanding manifestation of congenital bile duct atresia. Generally, there is no jaundice at birth, but it appears 1 to 2 weeks later and progresses progressively. The sclera and skin change from golden yellow to green-brown or dark green, the stool gradually turns into clay color, the urine color deepens to resemble strong black tea or urine, the skin becomes yellow with itching and scratching marks. Bleeding tendency and coagulation mechanism disorders may occur after 2 to 3 months.

　　2. Malnutrition and poor development

　　In the early stage, the child's condition is good, nutrition and development are normal, and the symptoms do not match the depth of jaundice. Subsequently, the condition gradually worsens, and by 3 to 4 months, malnutrition, anemia, developmental delay, and delayed response may occur.

　　3. Enlargement of the liver and spleen

　　Enlargement of the liver and spleen is a characteristic of congenital biliary atresia. The liver is normal at birth, but it progressively enlarges as the condition progresses, and it can develop into cholestatic liver cirrhosis and portal hypertension around 3 months. Ultimately, death often occurs within one year due to infection, bleeding, liver failure, and hepatic coma. Cyst rupture can lead to cholestatic peritonitis.

　　Secondly, Congenital Bile Duct Dilatation

　　The typical manifestations of congenital bile duct dilatation are a triad of abdominal pain, abdominal mass, and jaundice, with symptoms often presenting in intermittent attacks. Abdominal pain is located in the upper right abdomen and can be a persistent dull pain; jaundice is intermittent; more than 80% of patients can palpate a smooth cystic mass in the upper right abdomen. In cases of infection, jaundice may deepen, pain may worsen, the mass may be tender, and symptoms such as chills and fever may occur. In the late stage, clinical manifestations of cholestatic liver cirrhosis and portal hypertension may appear. Rupture of the cyst can lead to cholestatic peritonitis.

　　Congenital biliary tract abnormalities are congenital malformations, and congenital malformations are generally only preventable through prenatal examinations.

　　9. Take premarital medical examination seriously. Diseases found through the examination, such as hepatitis B and sexually transmitted diseases, are all diseases that can affect the health of offspring and cause fetal malformations. Pregnancy is only possible after these diseases are cured.

　　8. Prepare well before pregnancy, do not become pregnant blindly, and achieve a planned pregnancy with necessary checks, such as rubella virus detection. Rubella virus infection can lead to congenital heart disease and congenital deafness in the fetus, which can be prevented by vaccination against rubella virus. Folic acid tablets such as 'Salian' can be taken three months before pregnancy to prevent neural tube defects in the fetus.

　　7. Avoid pregnancy during spring and winter when there are more viruses. The incidence of fetal malformations in spring and winter is significantly higher than in summer and autumn.

　　6. Establish a perinatal health card immediately after pregnancy, and have regular check-ups. From 14 to 20 weeks, you can perform Down syndrome screening, and before 28 weeks, perform ultrasound detection, etc. These checks can detect fetal malformations in the early stages of pregnancy.

　　5. Preventing infectious diseases of the reproductive tract. Infectious diseases of the reproductive tract are mainly caused by unclean sexual behavior, so it is necessary to regulate sexual behavior, treat diagnosed cases promptly, and pregnant women should seek medical attention promptly if they find any abnormal discharge. They should not refuse medication or avoid medical treatment due to pregnancy.

　　Any baby born with persistent jaundice, clay-colored stools, and liver enlargement within 1 to 2 months should be suspected of having congenital biliary tract abnormalities. The following examinations should be performed to aid in diagnosis:

　　1. Jaundice that persists for more than 3 to 4 weeks and worsens progressively, with no response to bile duct medication; there is no reaction to phenobarbital and hormone treatment; serum bilirubin levels continue to rise;

　　2. There is no bile juice in the duodenal drainage fluid;

　　3. Ultrasound examination shows underdevelopment or absence of extrahepatic bile ducts and gallbladder;

　　4. 99mTC-EHIDA scan shows no radionuclide in the intestinal tract.

　　Congenital biliary anomalies are congenital diseases, and diet has no significant auxiliary therapeutic effect on the disease. It is recommended that women eat less fish during pregnancy. Although fish is generally recognized as a healthy food, different types of fish accumulate different amounts of mercury, which is a harmful natural element to humans. Therefore, pregnant women should avoid eating sharks, mackerel, swordfish, and bluefish. The mercury content in these four types of fish may affect the growth and development of the fetal brain and cause malformations of the bile duct and other organs. However, if pregnant women occasionally eat one or two meals, there is no major harm, because the harm of eating these fish lies in the long-term accumulation of mercury.

　　The treatment of congenital biliary anomalies generally chooses surgery, detailed as follows:

　　Firstly, Congenital Biliary Atresia

　　Once biliary atresia is diagnosed, surgery is the only treatment method. Any confirmed diagnosis or failure to rule out the disease should be treated with surgery as soon as possible to reconstruct the bile ducts. The optimal time for reconstructive surgery is within 60 days of birth. Beyond 3 months, secondary biliary cirrhosis may occur, leading to irreversible liver function damage, and the postoperative effect is poor. The choice of surgical method includes:

　　1. In cases where there is still some patency of the extrahepatic bile ducts and the gallbladder size is normal, Roux-en-Y anastomosis can be performed between the gallbladder or extrahepatic bile duct and the jejunum.

　　2. Complete obstruction of extrahepatic bile ducts, with bile ducts still present in the liver, can be treated with Kasai hepatic portal jejunal anastomosis.

　　3. Liver transplantation is suitable for patients with complete obstruction of the intrahepatic and extrahepatic bile ducts and those who are ineffective after Kasai surgery. Biliary atresia is the main indication for pediatric liver transplantation.

　　Secondly, Congenital Bile Duct Dilatation

　　Congenital bile duct dilatation should be operated on as soon as possible after diagnosis, otherwise it may cause serious complications such as liver cirrhosis, canceration, or cyst rupture due to recurrent cholangitis. Complete resection of the cyst and bile-enteric Roux-en-Y anastomosis is the main treatment method for congenital bile duct dilatation, with good efficacy. When resecting the cyst, it is only necessary to completely strip the mucosa of the cyst under the submucosa of the cyst, without the need to resect the cyst wall.