What is the treatment for Mirizzi syndrome?

Mirizzi Syndrome: Diagnosis and Management

Mirizzi syndrome is a rare complication of gallstone disease requiring surgical management, with open cholecystectomy being the preferred approach for most cases due to the high risk of bile duct injury with laparoscopic techniques. 1

Definition and Pathophysiology

• Mirizzi syndrome occurs when a gallstone becomes impacted in the cystic duct or gallbladder neck, causing extrinsic compression of the common hepatic duct or common bile duct, resulting in obstructive jaundice 1, 2
• It affects less than 1% of patients with gallstones and is considered an at-risk condition that requires thorough preoperative evaluation 1
• The condition may progress to form cholecystobiliary fistulas in advanced cases (Type II and above) 3

Clinical Presentation

• Right upper quadrant abdominal pain is the most common symptom, present in nearly all patients 4, 3
• Jaundice occurs in approximately 16.7% of patients 3
• Some patients may present with Charcot's triad (right upper quadrant pain, jaundice, and fever) suggesting cholangitis 5
• Abnormal liver function tests are found in about 44.4% of patients 3

Classification

• McSherry's classification divides Mirizzi syndrome into:
  • Type I: External compression of the common bile duct without fistula formation
  • Type II: Presence of a cholecystobiliary fistula 4, 3
• More detailed classifications include Types III-V based on the extent of fistula formation and bile duct involvement 3

Diagnostic Approach

• Preoperative diagnosis is crucial to prevent bile duct injury during surgery but is achieved in only 19.4-38.9% of cases 3, 5
• Ultrasonography is typically the initial imaging modality, showing:
  • Shrunken gallbladder
  • Impacted stone(s) in the cystic duct
  • Dilated intrahepatic biliary tree with normal-sized common bile duct 2
• CT scan helps differentiate Mirizzi syndrome from malignancy in the porta hepatis 2
• MRCP provides detailed biliary anatomy and shows inflammation around the gallbladder 2
• ERCP is the gold standard for diagnosis with 100% sensitivity, as it:
  • Delineates the cause, level, and extent of biliary obstruction
  • Identifies ductal abnormalities including fistulas
  • Offers therapeutic options like stone extraction and biliary stent placement 2, 4, 3

Treatment Approach

Preoperative Management

• Exhaustive preoperative workup is mandatory to balance risks and benefits of the procedure 1
• Preoperative ERCP may be used for both diagnosis and temporary biliary drainage in preparation for surgery 2

Surgical Management

• Open cholecystectomy is the current standard treatment for Mirizzi syndrome, with good short and long-term outcomes 1, 2
• Laparoscopic approach:
  • Generally considered contraindicated in many patients due to increased risk of complications 2
  • May be attempted in carefully selected Type I cases by experienced surgeons 4, 3
  • Has a high conversion rate to open surgery (30.55%) 3
• Surgical principles include:
  • Minimizing dissection in the triangle of Calot to avoid bile duct injury 6
  • Partial cholecystectomy may be the safest option in many cases 6
  • For Type II-V cases with fistula formation:
    • Smaller defects can be repaired with primary closure
    • Larger defects may require biliary reconstruction with hepaticojejunostomy 3, 5

Special Considerations

• If the Critical View of Safety (CVS) cannot be achieved during laparoscopic approach, a bailout procedure such as subtotal cholecystectomy should be considered 1
• In elderly patients or those with multiple comorbidities, endoscopic treatment may serve as an alternative to surgery 2

Outcomes and Prognosis

• Morbidity and mortality can be relatively high if not properly managed 6
• Late biliary strictures may develop in some patients, requiring long-term follow-up 6
• Successful surgical management with appropriate technique results in good outcomes in most patients 5

Prevention of Complications

• Early recognition of Mirizzi syndrome during surgery is crucial to avoid bile duct injury 5
• Intraoperative cholangiography may be helpful when biliary anatomy is unclear 1
• Conversion to open surgery should be considered whenever the operating surgeon cannot safely manage the procedure laparoscopically 1