Intrahepatic bile duct stones

　　The etiology of intrahepatic bile duct stone disease has not been elucidated to date. Because it involves multidisciplinary issues, such as medical geography, biochemistry, microbiology, pathophysiology, etc. In the past 20 years, with the progress of medical science and the deepening of basic research, many theories have been proposed on the etiology of intrahepatic bile duct stones. It is proposed that the pathogenic cause of intrahepatic bile duct stones is related to biliary bacterial infection, parasitic infection, and bile stasis.

　　1. Infection

　　Infection is the primary factor leading to the formation of stones, and the common causes of infection are biliary parasitic infection and recurrent cholangitis. Virtually all bile cultures of patients with intrahepatic bile duct stone disease can detect bacteria; the main bacteria come from the intestines, and common bacteria are Escherichia coli and anaerobic bacteria. The beta-glucuronidase produced by Enterobacteriaceae and some anaerobic bacteria and the endogenous glucuronidase produced during biliary infection can hydrolyze conjugated bilirubin to free bilirubin and precipitate.

　　2. Bile stasis

　　Bile stasis is a necessary condition for the formation of intrahepatic bile duct stones, and only under the condition of bile stasis can the components of bile sediment and form stones. The causes of bile stasis include biliary inflammatory stricture and biliary malformation. At the distal end of the obstructed bile duct, the pressure increases, the bile duct dilates, the bile flow is slow, which is conducive to the formation of stones. In addition, large molecular substances such as mucoprotein, acidic mucopolysaccharide, immunoglobulin, inflammatory exudates, desquamated epithelial cells, bacteria, parasites, and metal ions in bile all participate in the formation of stones.

　　The main pathological changes of intrahepatic bile duct stone disease are biliary obstruction and infection; due to the direct relationship between the biliary system and the liver parenchymal cells, severe cholangitis is often accompanied by severe liver cell damage, even leading to large areas of liver cell necrosis, which has become the main cause of death from benign biliary diseases. The complications of intrahepatic bile duct stones include acute complications and chronic complications.

　　1. Acute complications

　　The acute complications of intrahepatic bile duct stone disease are mainly biliary infections, including severe cholangitis, cholangogenic liver abscess, and accompanying infectious complications. The causes of infection are related to the obstruction of stones and the inflammatory stricture of the bile duct. Acute complications not only have a high mortality rate but also severely affect the surgical outcome.

　　2. Chronic complications

　　The chronic complications of intrahepatic bile duct stone disease include systemic malnutrition, anemia, hypoalbuminemia, chronic cholangitis, cholangogenic liver abscess, multiple biliary strictures, fibrosis and atrophy of liver lobes, biliary cirrhosis, portal hypertension, liver dysfunction, and delayed hepatobiliary cancer related to long-term biliary infection and bile stasis. The chronic complications of intrahepatic bile duct stone disease not only increase the difficulty of surgery but also affect the surgical outcome.

　　The clinical manifestations of intrahepatic bile duct stone disease can be varied depending on the course and pathology, ranging from early cases with no obvious clinical symptoms and stones localized in a segment of the intrahepatic bile duct to late-stage cases that affect the biliary system both inside and outside the liver, even leading to biliary cirrhosis, liver atrophy, and liver abscesses. Therefore, the clinical manifestations are very complex. The characteristics are:

　　1. The age of onset is between 30 to 50 years.

　　2. There may be upper abdominal pain, which may be typical biliary colic or persistent distension pain, with some patients having不明显 (not obvious) pain, but severe chills and fever, periodic attacks,

　　3. There may be a long history of biliary disease, or a history of acute cholangitis accompanied by chills, fever, and jaundice.

　　4. There may be constant pain and discomfort in the affected liver area and lower chest, often radiating to the back and shoulders.

　　5. When there is obstruction of one side of the hepatic duct, jaundice may be absent or very mild.

　　6. When complicated with severe cholangitis, the overall condition is more serious, and the recovery after an acute attack is slower.

　　7. During the examination, there is marked tenderness and percussion pain in the liver area, with the liver showing asymmetrical enlargement and tenderness.

　　8. The overall condition is significantly affected, with most patients having hypoproteinemia, and one-third of patients have significant anemia.

　　9. In the late stage, there may be signs of liver and spleen enlargement and portal hypertension.

　　During the intermission period of the course of intrahepatic bile duct stones, there may be no symptoms, or only mild discomfort in the upper abdomen. However, during the acute phase, symptoms such as acute suppurative cholangitis or varying degrees of Charcot's triad may occur, most likely caused by the presence of extrahepatic bile duct stones. The main clinical manifestations are acute cholangitis, including the triad of biliary obstruction (pain, chills, fever, jaundice) and the quintet of severe cholangitis.

　　The increase in patients with intrahepatic bile duct stones has prompted more and more people to pay attention to this disease, and it is precisely because of the continuous understanding of intrahepatic bile duct stones that people have begun to pay attention to their prevention.

　　1. Eat regularly, have meals on time for three times a day, especially breakfast, which is extremely important for patients with intrahepatic bile duct stones. The liver in the human body is responsible for secreting bile, which is stored in the gallbladder. The main function of bile is to digest fatty foods. If breakfast is skipped, the bile secreted at night will not be used and will remain in the gallbladder, causing bile excretion to be unsmooth, which can stimulate the formation of stones in the intrahepatic bile ducts or cause the existing stones to grow larger and increase in number. Therefore, it is best to eat foods containing vegetable oils for breakfast.

　　2. Drink plenty of water and exercise, as water can prevent all kinds of kidney stones, while exercise helps to expel them.

　　3. Maintain a cheerful spirit, scientifically arrange your rest and work schedule, and combine labor and rest with movement and stillness, avoiding long periods of sitting motionless at a desk.

　　4. Reasonable dietary habits, adjust diet, avoid high-energy, high-sugar, and high-cholesterol diets, fully supply essential fatty acids, vitamin C, and protein foods, limit fat, and reasonably arrange meals to prevent the phenomenon of excess caloric intake and weight gain.

　　5. Prevent and treat diseases such as cholecystitis, diabetes, nephritis, and parasitic infections, use hormones and lipid-lowering drugs reasonably, and try to avoid triggering factors.

　　Intrahepatic bile duct stones are a disease that can cause great harm to patients' bodies and is a common disease in clinical practice. It is a type of bile duct stones, referring to the stones in the bile ducts of the right and left hepatic ducts above the confluence. It can exist alone or coexist with extrahepatic bile duct stones. It is generally bilirubin stones. Intrahepatic bile duct stones often occur with extrahepatic bile duct stones. Severe complications caused by this disease are an important cause of death from benign bile duct diseases. Patients need to pay attention to this disease and not take it lightly. Once symptoms of the disease are found, it is necessary to consult a doctor and undergo further examination and diagnosis in order to receive timely treatment. The following are the laboratory tests needed for intrahepatic bile duct stones:

　　(1) Ultrasound diagnosis

　　Ultrasound is a non-invasive examination that is convenient and easy to perform, and it is the first choice for diagnosing intrahepatic bile duct stones. The ultrasound images are variable, and it is generally required that the bile ducts at the distal end of the stones have dilation before making a diagnosis of intrahepatic bile duct stones, as calcification of the intrahepatic ductal system also has a stone-like imaging appearance.

　　(2) CT diagnosis

　　Since intrahepatic bile duct stones are mainly pigmentary stones containing bilirubin calcium, with a high calcium content, they can be clearly shown on CT scans. CT can also show the position of the hilum, bile duct dilation, and changes in liver hypertrophy and atrophy. Systematic observation of the CT images of each layer can understand the distribution of stones in the intrahepatic bile ducts.

　　(3) X-ray cholangiography

　　X-ray cholangiography (including PTC, ERCP, TCG) is a classic method for diagnosing intrahepatic bile duct stones, which can generally make a correct diagnosis. X-ray cholangiography should meet the needs of diagnosis and surgery, and a good cholangiography should be able to fully understand the anatomical variations of the intrahepatic bile duct system and the distribution range of stones.

　　(4) Other auxiliary examinations

　　1. Bile duct pressure measurement

　　Through bile duct pressure measurement, it can be understood whether the bile excretion through the bile duct is normal. For a branch of intrahepatic bile duct stones, the clinical significance of bile duct pressure measurement is not great. However, for stones near the right and left hepatic ducts at the hilum with bile duct stenosis, bile excretion can be found to be poor, causing bile duct dilation and stasis above the lesion, and increased bile duct pressure. Now, there are electronic bile duct pressure gauges that can accurately measure the pressure within the bile ducts, and the choice of use should be based on the condition.

　　2. Radionuclide scintigraphy

　　The commonly used radionuclide 99mTc is injected intravenously and then absorbed by the reticuloendothelial system, excreted into the bile duct. The scan can be stratified and localized to obtain three-dimensional images, showing the relationship with adjacent structures, providing a good basis for diagnosis. However, it is not ideal for diagnosing intrahepatic bile duct stones.

　　3. Selective abdominal aortic angiography

　　Observe whether there is displacement, compression, occlusion, or abnormal vascular shadows in the arterial blood vessels. It is effective for differential diagnosis of cholangiocarcinoma and gallbladder cancer, but not ideal for the diagnosis of intrahepatic bile duct stones. Moreover, arteriography requires certain equipment, is complicated, and has high technical requirements, so it is not the first choice for the diagnosis of intrahepatic bile duct stones.

　　The liver and gallbladder are important digestive organs in the human body, and the bile secreted and concentrated by them is an important part of digestive juices. Maintaining a good mental state, avoiding various adverse psychological stimuli, and cultivating good living habits are also effective measures for the prevention and treatment of intrahepatic bile duct stones.

　　1. Minimize the intake of fats, especially animal fats, and avoid eating fatty meat and fried foods. Try to replace animal oil with vegetable oil as much as possible.

　　2. A considerable number of gallbladder inflammation and cholelithiasis are indeed related to high cholesterol content and metabolic disorders in the body. Therefore, it is necessary to limit the intake of high-cholesterol foods such as fish roe, yolks of various eggs, and livers, kidneys, hearts, and brains of various carnivorous animals.

　　3. The best way to cook food is steaming, boiling, stewing, and braising. It is strictly forbidden to consume large amounts of fried, baked, grilled, smoked, or preserved foods.

　　4. Increase the intake of foods rich in high-quality protein and carbohydrates, such as fish, lean meat, dairy products, fresh vegetables, and fruits, to ensure calorie supply and promote the formation of glycogen, protecting the liver.

　　5. Increase the intake of foods rich in vitamin A, such as tomatoes, corn, and carrots, to maintain the integrity of the gallbladder epithelial cells and prevent the shedding of epithelial cells to form the core of stones, thereby causing stones or increasing the size and number of stones.

　　6. If conditions permit, it is advisable to drink more fresh vegetable or melon juice, such as watermelon juice, orange juice, carrot juice, etc., and increase the frequency and quantity of drinking water and eating, in order to increase the secretion and excretion of bile, and alleviate inflammation and bile stasis.

　　7. Reduce the intake of vegetables rich in fiber, such as turnips and celery, to avoid increased peristalsis of the gastrointestinal tract due to difficult digestion, which may trigger biliary colic.

　　8. Quit smoking and drinking and reduce the intake of spicy and刺激性 foods, such as wasabi oil, to avoid stimulating the gastrointestinal tract and aggravating the condition.

　　9. It is advisable to consume light, easy-to-digest, low-fiber, temperature-appropriate, non-irritating, and low-fat liquid or semi-liquid foods. It is absolutely forbidden to eat and drink freely for the sake of temporary pleasure, as this may cause unnecessary troubles and even induce bile duct bleeding, which may be life-threatening.

　　Now, with the continuous improvement of medical level, the combination of surgery with dissolution and dissolution with stone excretion is widely used in clinical practice, making the treatment of intrahepatic bile duct stones more targeted and accurate, and at the same time, it is safer and more effective. Compared with the treatment of simple gallbladder stones and extrahepatic bile duct stones, the treatment of intrahepatic bile duct stones indeed has many difficulties, such as the inability to completely remove stones, the narrowing of intrahepatic bile ducts which is prone to poor bile drainage, and the recurrence of stones. At present, the main comprehensive treatment method for the treatment of intrahepatic bile duct stones is surgery-based:

　　1. Non-invasive Liver-Protective Stone Removal Surgery

　　Non-invasive liver-protective stone removal is based on ERCP endoscopy, using duodenal major papilla balloon dilation of the bile duct outlet, inserting ERCP fiber endoscope into the common bile duct, passing through the common bile duct to the intrahepatic bile duct, expanding the intrahepatic bile duct with a balloon, opening the lumen of the intrahepatic bile duct, unblocking the stone removal channel, and can completely remove intrahepatic bile duct stones in one go. The entire operation is performed under video visualization with endoscopic manipulation, painless, non-invasive, and without bleeding, completely curing intrahepatic bile duct stones in one go, preserving normal liver tissue.

　　2. Surgical Treatment

　　The purpose is to remove stones as cleanly as possible, relieve bile duct obstruction and stricture, eliminate intrahepatic infectious foci, and make bile excretion smooth. The main methods of surgery include:

　　①High-position bile duct incision for stone removal.

　　②Biliary-enteric internal drainage.

　　③Eliminate intrahepatic infectious foci, etc.

　　3. Treatment of residual stones

　　Once it is found that there are residual bile duct stones after the patient undergoes T-tube cholangiography after surgery, the T-tube can be removed after the sinus tract is formed, and a fiber胆道镜 can be inserted through the sinus tract to remove stones under direct vision using stone forceps, baskets, and other tools. If the stones are too large, laser碎石, micro-explosion破碎石, or other methods can be used to break the residual stones into small pieces before they are removed.

　　Generally, patients with intrahepatic bile duct stones have no obvious clinical symptoms, but this static state will not remain unchanged. When encountering adverse stimuli such as cold, overwork, or improper diet, the stones in the bile ducts of the patient's liver may change from 'static' to 'dynamic', thus causing corresponding symptoms. Therefore, patients should cooperate with doctors for long-term observation and prevention and treatment, regardless of whether there are symptoms, the number and size of the stones, or whether they cause liver lesions. Patients with conditions should also regularly undergo liver and gallbladder ultrasound examinations and liver function biochemical tests, so as to understand the location, nature of the stones, and whether there are secondary lesions in liver function at any time.