Mirizzi syndrome: what is it, symptoms, treatment, prognosis

What is Mirizzi Syndrome?

Mirizzi syndrome - a rare disease caused by obstruction of the common bile duct or common hepatic duct as a result of external compression with multiple injured gallstones or one large damaged gallstone in a sac Hartman. Symptoms are similar to cholecystitisbut can be confused with other obstructive conditions such as common bile duct stones and acute cholangitis due to availability jaundice. Preoperative diagnosis is often difficult and usually overlooked.

Eponym

The syndrome is named after Argentine surgeon Pablo Luis Mirizzi. He was born in 1893 in Cordoba, Argentina. Mirizzi graduated from the Faculty of Medicine of the National University of Cordoba in 1915. His most famous contribution to surgery is the performance of the first intraoperative cholangiography in 1931.

Causes and risk factors

Gallstones usually form from stagnant bile. When bile is not completely drained from the gallbladder, it can precipitate as silt and then turn into stones. Biliary obstruction can also lead to gallstones, including bile duct strictures, and cancer, such as 

pancreatic cancer.

The most common reason cholelithiasis (or cholelithiasis) - the deposition of cholesterol, which later turns into cholesterol stones. The second cause of gallstones is pigmented gallstones, which are the result of increased destruction erythrocytes in the intravascular system, causing an increased concentration of bilirubin, which subsequently accumulates in bile. These stones are usually black in color. The third type of gallstones are mixed pigmented stones, which are a combination of calcium substrates such as calcium carbonate or calcium phosphate, cholesterol, and bile. The fourth type is composed primarily of calcium and is commonly found in patients with hypercalcemia. When multiple gallstones or one large gallstone falls into Hartman's pouch (lower outlet gallbladder), external compression of the common bile duct or common hepatic duct may occur.

The exact mechanism of why this occurs is unknown, but it is believed to be due to the flexible sac. Hartmann containing a higher mass of stones, for example, with several stones or one big blow stone. This causes subsequent inflammation of the area, which can also lead to fistula formation over time.

Symptoms and Signs

Mirizzi's syndrome usually presents with acute or chronic cholecystitis with the addition of jaundice. Patients with chronic cholecystitis usually complain of a dull pain in the upper right corner of the abdomen that radiates to the middle of the back or the right tip of the scapula. This is usually associated with the intake of fatty foods. Nausea and intermittent vomiting also accompany complaints of increased bloating and flatulence. Symptoms often appear in the evening. Less severe, long-term symptoms usually appear over weeks or months. An increased frequency and severity of exacerbations (acute biliary colic) is usually seen with more prolonged chronic symptoms. A classic physical examination will show pain in the upper right corner of the abdomen with deep palpation (Murphy's sign). Patients are usually not severe, but uncomfortable. Patients with advanced Mirizzi syndrome or more severe acute cholecystitis may have more severe symptoms and signs. Jaundice is usually present, and sometimes significantly elevated bilirubin can be found.

Epidemiology

Mirizzi syndrome is relatively rare. The condition develops in only 0.1% of patients with gallstones, and it has been found in 0.7% to 25% of patients undergoing cholecystectomy. There may be an increase in morbidity among the elderly, but there was no predisposition for either men or women with gallstones. Also, there seems to be no prevalence among any particular ethnic group.

Pathophysiology

Gallstones occur when substances in the bile reach the solubility limit. As bile concentrates in the gallbladder, it becomes oversaturated with these substances, which eventually precipitate into small crystals. These crystals, in turn, become stuck in the gallbladder mucus, resulting in a gallbladder sediment. Over time, these crystals grow and form large and / or multiple stones. These gallstones can cause symptoms of cholecystitis, but if they enter Hartman's sac, they can cause additional symptoms of jaundice. As the condition progresses, internal fistulas may develop from the gallbladder to the common bile duct, common hepatic duct, and duodenum. A scoring system has been developed to classify the various stages of Mirizzi syndrome.

• Type I: compression of the common hepatic duct with a stone of the neck of the gallbladder or cystic duct;
• II type: vesicocholedocheal fistula, occupying less than 1/3 of the circumference of the common hepatic duct;
• III type: vesicocholedocheal fistula, occupying 2/3 of the circumference of the common hepatic duct;
• IV type: vesicocholedocheal fistula, occupying the entire circumference of the common hepatic duct (the duct wall is completely destroyed).

Diagnostics

First, a routine examination for cholecystitis is done. The best method for diagnosing gallstones and subsequent acute cholecystitis is an ultrasound examination of the right upper quadrant of the abdomen. It is associated with a specificity of 90% and, depending on the ultrasound operator, can detect stones up to 2 mm in size, as well as sludge and gallbladder polyps. Ultrasound findings that indicate acute cholecystitis versus cholelithiasis include thickening of the gallbladder wall (more than 3 mm), pericholecystic fluid and positive sonographic symptom Murphy.

Gallstones are also often found on CT and MRI, but these tests are not as sensitive in acute cholecystitis. Approximately 10% of gallstones can be found on ordinary plain films due to their high calcium content. Air in the biliary tree can also be detected on these x-rays if there is an intestinal fistula. If a common bile duct stone is suspected based on ultrasound results, magnetic resonance cholangiopancreatography (MRCP) is the next step.

If a common duct stone is found on MRCP, the gastroenterologist should perform endoscopic retrograde cholangiopancreatography (ERCP). A percutaneous transhepatic cholangiogram (PTC) is also useful for diagnosing common bile duct stones if ERCP is not possible. Typically, the diagnosis of Mirizzi syndrome is either mistaken for a simple bile duct stone or is completely missed on preoperative examination.

Treatment

Treatment of Mirizzi syndrome - cholecystectomy. Laparoscopic cholecystectomy is preferred, but more complex surgery may be required if the disease is advanced. Open cholecystectomy is possible. For more advanced disease, partial cholecystectomy may be considered. This requires leaving the Hartmann sac in place and removing the gallbladder body and gallstones. This will reduce the likelihood of damage to the liver gate and bile ducts. In the presence of a fistula, open cholecystectomy with bilioenteric anastomosis is effective.

Forecast

In patients without fistula formation, surgery and outcome are usually favorable. Due to the distorted anatomy and high conversion to open cholecystectomy on this occasion; however, some sources recommend an open surgical approach for all patients with Mirizzi syndrome. The prognosis for patients with fistula formation includes long-term treatment with the placement of a T-tube through a small and medium fistula size or diversion of the bile ducts with choledochoduodenostomy or choledochojejunostomy with gastric bypass for larger fistulas. A long surgical and hospital course for the latter group of patients increases the risk of complications and also increases the morbidity and mortality of these patients. Gallbladder cancer has also been associated with Mirizzi syndrome. Elderly patients with multiple comorbidities and a high risk of surgical complications, non-surgical methods should be considered to minimize complications associated with operation.

Complications

The most common complication of Mirizzi syndrome is the formation of a cholecystobiliary or cholecystointestinal fistula due to prolonged inflammation. Surgical complications with long procedure times due to tight adhesions can also occur. These include damage to the bile ducts and bleeding. In difficult cases, massive bleeding may occur when dissecting the Calot triangle. Other complications of prolonged inflammation that can be seen in patients with Mirizzi syndrome include:

• the formation of a skin fistula;
• secondary biliary cirrhosis;
• delayed strictures of the biliary tract.