From the Guidelines
Mirizzi syndrome is a rare condition where a gallstone becomes impacted in the cystic duct or the neck of the gallbladder, causing obstruction of the common bile duct.
Definition and Diagnosis
- It occurs in less than 1% of patients with gallstones 1.
- Pre-operative investigations may help in the diagnosis, although the vast majority of cases are identified at surgery 1.
Clinical Context
- Mirizzi syndrome mimics common bile duct stones (CBDS) and can be difficult to diagnose pre-operatively 1.
- The diagnosis of CBDS is often assessed with endoscopic retrograde cholangio-pancreatography (ERCP), which may be prompted by elevated liver function tests (LFTs) 1.
Key Points
- Gamma-glutamyl transpeptidase (GGT) is the most reliable LFT for diagnosing CBDS, with a sensitivity of 80.6% and a specificity of 75.3% 1.
- The presence of elevated LFTs, particularly GGT, may indicate the need for further diagnostic tests to rule out CBDS or Mirizzi syndrome 1.
From the Research
Definition and Characteristics of Mirizzi Syndrome
- Mirizzi syndrome (MS) is a rare complication of chronic gallstones, characterized by an obstruction of the proximal bile duct due to extrinsic compression by either an impacted stone in the gallbladder neck or local inflammatory changes 2.
- It is caused by the impact of one or more gallstones in the infundibulum of the gallbladder or cystic duct, leading to compression of the adjacent bile duct, resulting in partial or complete obstruction of the common hepatic duct 3.
- MS can result in compression of the hepatic duct or fistula formation between the gallbladder and common bile duct (or hepatic duct, right hepatic duct, or even mutative right posterior hepatic duct) 4.
Clinical Features and Diagnosis
- The most common symptoms of MS include abdominal pain, nausea/vomiting, and jaundice 2.
- MS must be in the differential diagnosis in elderly patients with chronic gallstone cholecystitis presenting with obstructive jaundice 5.
- Diagnostic methods for MS include endoscopic retrograde cholangiopancreatography (ERCP), magnetic resonance cholangiopancreatography (MRCP), and ultrasound 3, 6.
- ERCP is considered the most accurate diagnostic method for MS 3.
Treatment and Management
- The traditional treatment for MS has been surgery, involving an incision at the bottom of the gallbladder and calculus removal 3.
- Laparoscopic cholecystectomy may be possible in selected type I cases, but it is considered controversial and technically challenging 2, 3.
- Endoscopic treatment includes biliary drainage and stone extraction 3.
- Open cholecystectomy is the standard of care for type II MS 2.