Overview

Definition:
-Mirizzi syndrome is a condition characterized by extrinsic compression of the common hepatic duct (CHD) or the common bile duct (CBD) by a gallstone impacted in the cystic duct or the gallbladder's infundibulum
-This compression leads to partial or complete obstruction of bile flow, mimicking a malignant biliary obstruction.
Epidemiology:
-It is a relatively rare complication of cholelithiasis, occurring in approximately 0.1% to 4% of patients undergoing surgery for gallstones
-More common in elderly patients and those with chronic gallstone disease
-Some studies suggest a slight female predilection.
Clinical Significance:
-Accurate diagnosis and appropriate surgical management are crucial to prevent complications such as cholangitis, liver abscess, biliary fistula, and pancreatitis
-Failure to recognize Mirizzi syndrome can lead to suboptimal surgical outcomes and increased morbidity.

Clinical Presentation

Symptoms:
-Jaundice, often fluctuating or progressive
-Right upper quadrant (RUQ) pain, typically dull or colicky
-Fever and chills, suggestive of cholangitis
-Nausea and vomiting
-Pruritus due to cholestasis
-Abdominal distension
-Weight loss (less common, but can occur in advanced cases).
Signs:
-Jaundice (icteric sclerae and skin)
-RUQ tenderness on palpation
-Palpable gallbladder (Courvoisier's sign) may be present if there is associated distal CBD obstruction
-Hepatomegaly in some cases
-Signs of cholangitis (fever, tachycardia, RUQ tenderness - Charcot's triad)
-Signs of sepsis (hypotension, altered mental status) if severe cholangitis is present.
Diagnostic Criteria:
-No universally accepted strict diagnostic criteria exist, but the diagnosis is primarily based on a combination of clinical suspicion, imaging findings, and exclusion of other causes of biliary obstruction
-The presence of a gallstone in the cystic duct/infundibulum causing extrinsic compression of the CHD/CBD is the hallmark.

Diagnostic Approach

History Taking:
-Detailed history of gallstone-related symptoms (biliary colic, cholecystitis)
-Duration and progression of jaundice
-Presence of fever or chills
-Previous episodes of cholangitis or pancreatitis
-History of abdominal surgery
-Any known comorbidities.
Physical Examination:
-Thorough abdominal examination focusing on RUQ tenderness, guarding, and rebound tenderness
-Assessment for hepatomegaly and Courvoisier's sign
-Examination for signs of cholangitis and sepsis
-General assessment for signs of chronic liver disease.
Investigations:
-Liver function tests (LFTs): Elevated bilirubin (direct and indirect), alkaline phosphatase, and GGT
-ALT and AST may be elevated
-Complete blood count (CBC): Leukocytosis may indicate cholangitis
-Ultrasound (USG) abdomen: Initial imaging of choice, may show gallstones, thickened gallbladder wall, dilated intra- or extrahepatic bile ducts, and a stone in the cystic duct/gallbladder neck
-Computed tomography (CT) scan: Useful for assessing extent of ductal dilation, presence of stones, and ruling out extrinsic compression by masses
-can also identify fistulas
-Magnetic resonance cholangiopancreatography (MRCP): The gold standard for visualizing the biliary tree, demonstrating the level of obstruction, the impacted stone, and the presence of a cholecystobiliary fistula
-Endoscopic retrograde cholangiopancreatography (ERCP): Primarily therapeutic, but can also be diagnostic
-useful for stone extraction and stent placement if surgery is delayed or not immediately feasible
-Endoscopic ultrasound (EUS): Can provide detailed visualization of the gallbladder, cystic duct, and proximal CBD.
Differential Diagnosis:
-Malignancy of the common hepatic duct or pancreas head
-Cholangiocarcinoma
-Pancreatic adenocarcinoma
-Gallbladder cancer invading the bile duct
-Primary sclerosing cholangitis
-Benign biliary strictures
-Choledocholithiasis with secondary inflammation
-Parasitic infestation of the bile ducts.

Management

Initial Management:
-Fluid resuscitation and correction of electrolyte imbalances
-Broad-spectrum antibiotics for suspected cholangitis
-Analgesia for pain control
-Nutritional support
-Preoperative optimization for surgery.
Medical Management:
-Primarily supportive
-Antibiotics are essential for treating cholangitis.ursodeoxycholic acid (UDCA) may be considered for symptom management in some cases of cholestasis, though its role in Mirizzi syndrome is limited.
Surgical Management:
-Surgery is the definitive treatment
-The approach depends on the type of Mirizzi syndrome and the surgeon's expertise
-Type I: Gallstone in cystic duct/infundibulum causing extrinsic compression
-Standard cholecystectomy is usually sufficient
-Care must be taken to avoid avulsion of the CHD
-Type II: Gallstone erodes into the CHD/CBD, forming a cholecystobiliary fistula
-Requires careful dissection
-Options include: 1
-Cholecystectomy with management of the fistula: If the fistula is small and the CHD/CBD lumen is adequate, cholecystectomy alone may suffice, with spontaneous closure of the fistula
-2
-Cholecystectomy with primary repair of the CHD/CBD: If the fistula is large or causes significant ductal defect, primary repair may be necessary
-3
-Transhepatic or trans-cystic duct stenting: May be used to maintain bile flow across the repaired area
-4
-Hepaticojejunostomy (Roux-en-Y): Reserved for complex cases with extensive damage to the CHD/CBD or when other methods fail
-Laparoscopic vs
-Open Surgery: Laparoscopic cholecystectomy can be performed in Type I Mirizzi syndrome
-For Type II, it is technically more challenging and may require conversion to open surgery
-A cautious approach with intraoperative cholangiography is recommended
-Recognition of the fistula is key
-Sometimes, a staged approach (e.g., ERCP for decompression followed by surgery) might be considered.
Supportive Care:
-Close monitoring of vital signs, fluid balance, and LFTs postoperatively
-Pain management
-Early ambulation
-Gradual resumption of oral intake
-Monitoring for complications like cholangitis, sepsis, fistula formation, or bile leak.

Complications

Early Complications:
-Bile leak from the cystic duct stump or CHD/CBD
-Cholangitis
-Pancreatitis
-Hemorrhage
-Injury to the CHD/CBD or hepatic artery
-Formation of a cholecystobiliary fistula if not recognized and managed
-Abscess formation.
Late Complications:
-Biliary strictures leading to recurrent cholangitis or secondary biliary cirrhosis
-Recurrent choledocholithiasis
-Cholangiocarcinoma (increased risk due to chronic inflammation)..
Prevention Strategies:
-Meticulous surgical technique during cholecystectomy
-Careful dissection of the cystic duct and common bile duct
-Intraoperative cholangiography to identify anatomical variations and stones
-High index of suspicion for Mirizzi syndrome based on preoperative imaging and intraoperative findings
-Prompt recognition and management of any intraoperative bile duct injury or fistula.

Prognosis

Factors Affecting Prognosis:
-The type of Mirizzi syndrome (Type I generally has a better prognosis than Type II)
-The extent of biliary tree damage
-Presence of cholangitis or sepsis at presentation
-Surgeon's experience
-Promptness and appropriateness of surgical intervention.
Outcomes:
-With appropriate surgical management, the prognosis is generally good
-Most patients with Type I Mirizzi syndrome recover uneventfully after cholecystectomy
-Patients with Type II Mirizzi syndrome may have a higher risk of complications and may require more complex reconstructive procedures
-Long-term outcomes are usually favorable if complications are avoided.
Follow Up:
-Regular follow-up appointments are recommended to monitor for recurrent symptoms, signs of biliary stricture, or other late complications
-LFTs may be checked periodically
-Imaging (USG or MRCP) may be considered if symptoms recur
-Duration of follow-up depends on the complexity of the case and presence of any complications.

Key Points

Exam Focus:
-Mirizzi syndrome is extrinsic compression of CHD/CBD by cystic duct stone
-Types I (compression) vs
-II (fistula)
-MRCP is key for diagnosis
-Surgery is definitive
-Laparoscopic approach is feasible for Type I, challenging for Type II
-Be wary of bile duct injury.
Clinical Pearls:
-Always consider Mirizzi syndrome in patients with jaundice and gallstones, especially if imaging suggests a stone in the cystic duct/gallbladder neck
-Intraoperative cholangiography is invaluable
-If a fistula is encountered, do not force dissection
-consider conversion to open or staged management.
Common Mistakes:
-Misdiagnosing Mirizzi syndrome as a malignant obstruction, leading to unnecessary extensive oncological resections
-Aggressive dissection in Type II Mirizzi leading to severe bile duct injury
-Inadequate management of the cholecystobiliary fistula
-Performing routine cholecystectomy in Type II without considering the fistula, leading to bile leak or stricture.