What is the cause of common bile duct stones ppt

Common bile duct stones are a relatively common disease. Patients with this disease will usually experience pain symptoms, and the liver will continue to grow larger as the disease worsens. For patients, they may have had chronic cholecystitis or roundworms in their stomachs. Many people initially experience abdominal pain and are then diagnosed with common bile duct stones. So, what is the cause of common bile duct stones?

1. Causes of disease

Secondary common bile duct stones (28%):

The shape, size, and properties are basically the same or similar to those of the coexisting gallstones. The number varies and may be single or multiple. If the diameter of the multiple stones in the gallbladder is small and there is obvious dilation of the cystic duct, a large number of stones can enter the common bile duct, common hepatic duct, or left and right hepatic ducts.

Primary common bile duct stones (35%):

It is a primary bile duct stone that occurs in the common bile duct. The cause and formation mechanism are not yet fully understood. Current research results believe that the formation of this type of stone is closely related to bile duct infection, bile stasis, and bile duct parasitic diseases. The stones are mostly brown in appearance, soft, fragile, and of various shapes, sizes, and numbers. Some are like fine sand or shapeless mud, so they are called "mud-like stones". The composition of this type of stone is mainly pigmented stones with bilirubin calcium. Analysis shows that the main components are bilirubin, biliverdin and a small amount of cholesterol, as well as minerals such as calcium, sodium, potassium, phosphorus, magnesium, and a variety of trace elements. Among the minerals, calcium ions have the highest content and are easily combined with bilirubin to form bilirubin calcium. In addition, there are a variety of proteins and mucins that form a reticular scaffold. In some cases, the shell skin, eggs, and bacterial aggregation of parasites can be seen under a microscope.

2. Pathogenesis

The pathological changes that this disease may cause are basically determined by two factors:

① Whether the obstruction is complete: It depends on the size and location of the stone, and is also related to the functional state of the common bile duct sphincter.

② Whether there is secondary infection: It depends on the cause and nature of the stones. The scope and severity of the inflammation also vary greatly.

Common bile duct obstruction caused by stones is usually incomplete or intermittent, because stones can move or slide in the bile duct; but sometimes it can cause complete acute obstruction. Although secondary stones that enter the common bile duct from the gallbladder are small in size, the obstruction caused is often acute, especially when the stones are lodged in the ampulla, which may cause temporary complete obstruction. On the contrary, if it is a primary common bile duct stone, it will gradually grow larger and may reach a huge size in the later stage, but because the common bile duct can have corresponding compensatory expansion, it generally will not cause complete obstruction, and sometimes there may not even be any obstruction symptoms. This is related to the location of the stone. If the stone is located in the middle section of the common bile duct, it generally only has incomplete obstruction, but stones lodged in the ampulla or blocking the hepatic duct can sometimes cause complete obstruction.

Generally speaking, stones must be removed through surgery so that the patient can have a chance to recover. However, surgery may not be suitable for common bile duct stones, because for some patients who are in the acute attack phase, the location and size of the stones cannot be diagnosed, so emergency surgery should be avoided at this time.