After the obstruction caused by the cervical duct of gallbladder, the water in the gallbladder does not flow, and the accumulated water is like stagnant water in a pool, which easily causes bacteria to breed and multiply and become infected, thus forming pus in the gallbladder. The bile turns into foul-smelling pus, and later the pressure inside the gallbladder gradually increases, affecting the blood and lymphatic circulation of the mucous membrane of the gallbladder wall, gradually causing ulcers and necrotic lesions on the mucous membrane of the gallbladder wall, and in severe cases, large areas of necrosis and perforation can occur. Cholecystitis is a relatively common disease with a high incidence. According to its clinical manifestations and clinical course, it can be divided into two types: acute and chronic, often in combination with cholelithiasis. The onset of acute cholecystitis is closely related to biliary stasis and bacterial infection. The main pathogenic bacteria of cholecystitis are Escherichia coli (60% to 70%), Klebsiella, anaerobic bacteria and other gram-negative bacteria, which mostly enter the gallbladder retrograde from the intestine via the common bile duct, and a few enter the gallbladder via the portal venous system to the liver and then flow into the gallbladder with bile. Chronic cholecystitis is partly a result of acute cholecystitis, but most do not have a history of previous acute attacks. About 70% of patients have stones. Due to the stimulation of gallstones, and on the basis of long-term chronic inflammation, there have been repeated acute attacks, which can lead to atrophy of the gallbladder or hypertrophy of the fibrous tissue of the cystic wall, eventually leading to shrinkage of the cystic cavity and loss of function. If the gallbladder duct is completely blocked by stones, inflammatory adhesions or scars, bile cannot flow into the gallbladder, while the original bile in the gallbladder is gradually absorbed due to bile pigment, the mucous membrane still keeps secreting colorless watery mucus (white bile), which can form gallbladder fluid; when secondary infection occurs, it will evolve into gallbladder pus.