bubble_chart Overview

Acute calculous cholecystitis is caused by the obstruction of the cystic duct by stones, leading to the retention of bile in the gallbladder, which subsequently results in bacterial infection and acute inflammation. In acute acalculous cholecystitis, the cystic duct is often not obstructed. The cause of the disease is unclear in most patients. It often occurs after trauma or abdominal surgeries unrelated to the biliary system.

bubble_chart Etiology

The onset of acute calculous cholecystitis is caused by the obstruction of the cystic duct by stones, leading to the retention of gall fel in the gallbladder, which subsequently results in bacterial infection and acute inflammation. If the inflammation only occurs in the mucosal layer of the gallbladder, causing congestion and edema, it is referred to as acute simple cholecystitis. If the inflammation spreads to the entire layer of the gallbladder, filling it with pus, and there is purulent fibrinous exudate on the serosal surface, it is called acute suppurative cholecystitis. The gallbladder may become extremely distended due to the accumulation of pus, leading to ischemia and gangrene of the gallbladder wall, which is known as acute gangrenous cholecystitis. The necrotic gallbladder wall may perforate, resulting in biliary peritonitis. Perforation of the gallbladder usually occurs at the fundus, the impacted stone in the ampulla, or the neck of the gallbladder. If the gallbladder perforates into adjacent organs such as the duodenum, colon, or stomach, it can cause internal biliary fistula. At this point, the acute inflammation in the gallbladder can be drained through the fistula, and the inflammation can quickly subside, alleviating symptoms. If the pus in the gallbladder enters the common bile duct, it can cause acute cholangitis, and a few people may also develop acute pancreatitis. The pathogenic bacteria are mostly Escherichia coli, Klebsiella, and Enterococcus faecalis, with anaerobic bacteria accounting for 10-15%, but sometimes as high as 45%.

In acute acalculous cholecystitis, the cystic duct is usually not obstructed. The cause of the disease is unclear in most patients. It often occurs after trauma or abdominal surgery unrelated to the biliary system, and sometimes in children with non-hemolytic anemia. It is generally believed that factors such as dehydration, fasting, the use of anesthetic analgesics, and severe stress reactions after surgery and trauma lead to reduced gallbladder contraction, retention of gall fel, and decreased resistance of the gallbladder mucosa, which then results in secondary bacterial infection and ultimately acute inflammation of the gallbladder. Some cases are thought to be caused by acute embolism of the gallbladder's nutrient vessels. The pathological progression of this type of acute acalculous cholecystitis is similar to that of calculous cholecystitis, but the disease progresses rapidly, usually developing into gangrenous cholecystitis within 24 hours, and manifests as gangrene of the entire gallbladder.

bubble_chart Clinical Manifestations

Approximately 85% of patients with acute cholecystitis experience paroxysmal colicky pain in the upper middle and upper right abdomen during the initial stage [first stage], with referred pain to the right subscapular region. This is often accompanied by nausea and vomiting. Fever typically ranges between 38～39°C, without shivering. 10～15% of patients may exhibit grade I jaundice. Physical examination reveals tenderness and muscle rigidity in the upper right abdomen, with a positive Murphy's sign. In about 40% of patients, an enlarged and tender gallbladder can be palpated in the middle and upper right abdomen. White blood cell counts often show a grade I increase, generally between 10,000～15,000/mm³. If the condition progresses to gallbladder gangrene, perforation, and leads to gall bladder-induced peritonitis, systemic infection symptoms may significantly worsen, accompanied by shivering, high fever, increased pulse rate, and a marked rise in white blood cell count (usually exceeding 20,000/mm³). At this stage, local signs include an expanded area and increased severity of tenderness and muscle rigidity in the upper right abdomen. Generally, acute cholecystitis has minimal impact on liver function, or may only present with grade I liver function impairment, such as slight elevations in serum bilirubin and alanine aminotransferase levels. The clinical manifestations of acalculous cholecystitis are similar to those of calculous cholecystitis but are often atypical.

bubble_chart Diagnosis

Acute calculous cholecystitis can be diagnosed primarily based on clinical manifestations and B-ultrasound examination. B-ultrasound can reveal an enlarged gallbladder with thickened walls, often exceeding 3mm, and in 85-90% of cases, it can show the shadow of gallstones. When there is doubt in the diagnosis, isotope 99mTc-IDA can be used for biliary system scanning and imaging. The imaging often shows the bile ducts, but the gallbladder does not appear due to obstruction of the cystic duct, thereby confirming the diagnosis of acute cholecystitis. The accuracy rate of this method can exceed 95%. The diagnosis of acute acalculous cholecystitis is more challenging. The key to diagnosis lies in considering the possibility of the disease when the aforementioned clinical manifestations of acute cholecystitis appear after trauma or abdominal surgery. In a few cases of acute emphysematous cholecystitis caused by gas-forming bacteria, a plain film of the gallbladder area can reveal the presence of gas in both the gallbladder wall and cavity.

bubble_chart Treatment Measures

For mild cases of acute simple cholecystitis, non-surgical therapy may be considered initially to control inflammation, followed by elective surgery after further investigation of the condition. For more severe cases of acute suppurative or gangrenous cholecystitis or gallbladder perforation, timely surgical treatment is necessary, but preoperative preparation must be thorough, including correcting typical edema, electrolyte and acid-base balance disorders, and the use of antibiotics. Non-surgical therapy is effective for most (about 80-85%) patients with early acute cholecystitis. This method includes antispasmodic and analgesic treatment, antibiotic application, correction of typical edema, electrolyte and acid-base balance disorders, and systemic supportive therapy. During non-surgical therapy, close observation of the condition is essential. If symptoms and signs progress, timely surgical treatment should be adopted. Especially for elderly patients and those with diabetes, the condition can change rapidly and requires more attention. Statistics show that about 1/4 of patients with acute cholecystitis will develop gallbladder gangrene or perforation. For patients with acute acalculous cholecystitis, due to the rapid progression of the disease, non-surgical therapy is generally not adopted. It is advisable to perform timely surgical treatment after thorough preoperative preparation. Regarding the use of antibiotics in acute cholecystitis, since the cystic duct is blocked, antibiotics cannot enter the gallbladder with gall fel and cannot effectively control the infection within the gallbladder. The occurrence of cholecystitis and its complications is not influenced by the use of antibiotics. However, the application of antibiotics can achieve a certain therapeutic concentration in the blood, reducing systemic infections caused by cholecystitis and effectively decreasing postoperative infectious complications. For patients with fever and high white blood cell counts, especially the elderly or those with diabetes and long-term use of immunosuppressants who are highly susceptible to infection, systemic antibiotic application is still very necessary. Broad-spectrum antibiotics such as gentamicin, chloramphenicol, cephalosporins, or ampicillin are generally used, often in combination.

Surgical treatment: There is still debate over the timing of surgery, but it is generally believed that early surgery should be adopted. Early surgery does not mean emergency surgery, but rather surgery performed after a period of non-surgical treatment and preoperative preparation, and further diagnosis confirmation with B-ultrasound and isotope examination, within 72 hours of the onset of the disease. Early surgery does not increase the mortality and complication rates of surgery. For patients who respond well to non-surgical treatment, delayed surgery (or advanced stage surgery) can be adopted, usually performed after 6 weeks.

There are two surgical methods: one is cholecystectomy. During the acute phase, the tissues around the gallbladder are edematous, and the anatomical relationships are often unclear, so the operation must be performed carefully to avoid damaging the bile duct and adjacent important tissues. When conditions permit, intraoperative cholangiography should be used to detect bile duct stones and possible bile duct malformations. The other surgical method is cholecystostomy, mainly used for some elderly patients in poor general condition or with severe cardiopulmonary diseases who are estimated to be unable to tolerate cholecystectomy. Sometimes, when the anatomy around the gallbladder is unclear during the acute phase, making the operation difficult, cholecystostomy can be performed first. Cholecystostomy can be performed under local anesthesia, aiming to drain the cholecystitis with a simple method to help the patient survive the critical period. After the patient's condition stabilizes, usually 3 months after cholecystostomy, cholecystectomy is performed to cure the lesion. For cholecystitis complicated by acute cholangitis, in addition to cholecystectomy, common bile duct exploration and T-tube drainage must also be performed simultaneously.

With the increasing incidence of cholelithiasis in the elderly population, the number of elderly patients with cholecystitis is also continuously rising. Cholecystitis in the elderly has its unique characteristics in its onset: ① The clinical manifestations are relatively vague, and routine laboratory test results often cannot accurately reflect the severity of the lesions. There is a high risk of gangrene and perforation, often accompanied by complications involving the heart, blood vessels, lungs, liver, kidneys, and other internal organs. ② The overall disease resistance and immune function are weakened, leading to poor tolerance for surgery. The postoperative complication and mortality rates are higher than in the general population, especially for emergency surgeries, where the mortality rate can sometimes reach 6-7%. Therefore, for the treatment of elderly patients with cholecystitis, non-surgical treatment should be considered first. If surgery is necessary, elective cholecystectomy should be performed after infection control. However, on the other hand, if surgical indications are clear, early and proactive surgery should still be pursued, with simplified procedures such as cholecystostomy to temporarily alleviate acute conditions.