Biliary fistulas are rare complications of gallstone. They can affect either the biliary or the gastrointestinal tract and are usually classified as primary or secondary. The primary fistulas are related to the biliary lithiasis, while the secondary ones are related to surgical complications. Laparoscopic surgery is a therapeutic option for the treatment of primary biliary fistulas. However, it could be the first responsible for the development of secondary biliary fistulas. An accurate preoperative diagnosis together with an experienced surgeon on the hepatobiliary surgery is necessary to deal with biliary fistulas. Cholecystectomy with a choledocoplasty is the most frequent treatment of primary fistulas, whereas the bile duct drainage or the endoscopic stenting is the best choice in case of minor iatrogenic bile duct injuries. Roux-en-Y hepaticojejunostomy is the extreme therapeutic option for both conditions. The sepsis, the level of the bile duct damage, and the involvement of the gastrointestinal tract increase the complexity of the operation and affect early and late results.
Biliary fistulas are defined as chronic pipe-like ulcers. They can connect the gallbladder with the biliary tree and rarely involve the gastrointestinal tract (internal fistulas) and the abdominal wall (external fistulas) [
Internal fistulas are always caused by inflammation and occur mainly as late complications of gallstone or hydatid diseases, like biliobronchial fistulas [
External fistulas are related to the iatrogenic injury of the biliary tract and are infrequent compared to primary fistulas.
The incidence of the primary biliary fistulas is ranged from 1 to 2%, in symptomatic patients; in Latin America it is more common (4.7–5.7%) [
The complication rate of open cholecystectomy has increased for two reasons: the overall declining experience in the open approach and its use only in challenging cases [
Since only 20–30% of the patients affected by gallstone are symptomatic [ jaundice exists when stricture of the bile duct is associated with the fistula (Mirizzi’s Syndrome); cholangitis and sepsis exist when bacterial overgrowth is associated with the inflammation of the gallbladder and the biliary tract; bowel occlusion occurs when the passage of large stones in the alimentary tract causes obstruction of the small bowel, usually in the terminal ileum (Bouveret’s syndrome); derangement of hepatic function tests is variably present; aerobilia, at the Rx abdominal plain or CT, is a pathognomonic sign of biliary fistulas.
Kehr was the first who described gallstone obstruction of the hepatic duct in 1905 [
In 1942, Puestow [ Type 1 lesion is the external compression of the common bile duct due to a gallstone impacted at the neck of the gallbladder or at the cystic duct (the original Mirizzi’s syndrome). Type 2 lesion is the presence of a cholecystobiliary fistula (cholecystohepatic or cholecystocholedochal) due to the erosion of the anterior or lateral wall of the common bile duct by impacted stones; the fistula involves less than one-third of the circumference of the common bile duct. Type 3 lesion is the presence of a cholecystobiliary fistula with erosion of the wall of the common bile duct that involves up to two-thirds of its circumference. Type 4 lesion is the presence of a cholecystobiliary fistula with complete destruction of the entire wall of the common bile duct.
This physiopathological process begins with the impact of the stones and continues with the erosion of the gallbladder and the common bile duct wall. The fistula can involve the biliary tract and nearby gastrointestinal structures. Based on this physiopathological process, cholecystoenteric fistulas must be considered the late evolving stages of the Mirizzi’s Syndrome.
Classification of the Mirizzi’s Syndrome by Csendes.
In 2008, Beltran et al. [ cholecystoduodenal fistulas: 40%; cholecystocolic fistulas: 28%; cholecystogastric: 32%.
Large stones, recurrent cholangitis, female sex, and old age are risk factors for bilioenteric fistulas [
Secondary biliary fistulas are caused by iatrogenic injury during cholecystectomy, either performed by open or laparoscopic surgery. The main condition favoring injury is an unclear anatomy of the biliary tract due to local peritonitis, inflammation, or bleeding during the operation. The failure to identify the anatomical landmarks within the Calot’s triangle is the most frequent reason of the bile duct injury [ type I: transection > 2 cm from the confluence; type II: transection < 2 cm from the confluence; type III: transection in the hilum; type IV: separation of the major ducts in the hilum; type V: transection injury of aberrant right hepatic duct plus injury in the hilum.
This classification refers to open surgery and it is very useful to plane the surgical operation, but it does not consider the mechanisms leading to biliary duct damage during laparoscopic cholecystectomy. Wrong clipping of the cystic duct or thermal injury by cautery in dissecting Calot’s structures may cause lateral damage of the bile ducts. The classification of the injuries into 5 types proposed by Schmidt et al. allows us to distinguish between lateral damage and complete section or closure of the bile duct [
When the output of the fistula is high (usually >100 mL/day for few days), endoscopic treatment is indicated to avoid a future stenosis. Major damage on the bile ducts (i.e., complete transection) should be treated by a surgeon with a sufficient experience in the advanced biliary surgery.
The preoperative diagnosis of the biliary fistulas is challenging and it is achieved only in 8–17% of the cases [
To plan the best operation, we need to know the cause of the fistula: the presence of gallstones is the most frequent pathological condition; in the absence of stones, other inflammatory conditions or neoplasia should be searched for; the level of obstruction of the biliary tract and the presence of erosion/destruction of the wall; the presence of bilioenteric fistula, easily recognizable by aerobilia and/or biliary ileus.
The presence of gallstones is easily demonstrated by noninvasive diagnostics.
Transabdominal US has a sensitivity of 96% regarding gallstones detection [
Magnetic resonance cholangiopancreatography (MRCP) has a better diagnostic accuracy (about 50% of the cases) and provides better information of the anatomy of the biliary tree and the gallbladder [
Dilatation of the intrahepatic bile ducts with a normal choledochus (personal observation).
The level of obstruction is easily demonstrated by CT, which is also useful to exclude neoplastic lesions located at the hepatic hilum or into the liver [
Level of obstruction (personal observation).
Aerobilia is evident using either US or CT. Bowel obstruction by a biliary stone is typically evident in the CT scans (Figures
Aerobilia (personal observation).
Duodenal fistula and bowel obstruction (personal observation).
Invasive procedures, like endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP), have a higher diagnostic accuracy [
The diagnosis of biliary injury can be reached during cholecystectomy, performed with an opening of laparoscopic surgery. The use of intraoperative cholangiography is useful to identify the site and size of the damage, the presence of common bile duct stones, the presence of stenosis, and other pathological conditions. The correct intraoperative diagnosis allows us to correct the damage immediately, without inflammation and peritonitis [
ERCP is useful both for diagnosis (accuracy 95%) [
The surgical treatment of primary biliary fistulas is a challenge for surgeons.
A good knowledge of the pathology, the damage on the biliary tree, and the involvement of the alimentary tract is necessary. The inflammation in Calot’s triangle causes a significant derangement of the anatomy of the hilum region and may expose the surgeon to intraoperative injury of the bile duct.
Laparoscopic surgery can be applied to type I Mirizzi’s Syndrome and treatment of biliary ileus [
In type 2 Mirizzi’s Syndrome, where a limited involvement of the biliary tract is present, the operation should include a subtotal cholecystectomy, leaving a remnant gallbladder wall (5 mm in size) to perform the reconstruction of the bile duct. The drainage of the bile duct by T tube is performed to protect the choledocoplasty. Laparoscopic surgery is difficult, and it is made only in favourable conditions. Robotic surgery, consisting of subtotal cholecystectomy, associated with plastic stent insertion at ERCP, has been successful in a personal limited series [
In type 3 fistulas, the best treatment is the subtotal cholecystectomy with choledocoplasty, but an hepaticojejunostomy should be also considered when the damage is large, as in type 4 fistulas [
In type 5 fistulas, the presence of biliary ileus allows for an emergency treatment; in the absence of septic complications, the operation consists of enterotomy and stone extraction (it can be performed laparoscopically) with delayed treatment of the cholecystoenteric fistula. When septic complications occur, the operation needs also the treatment of the fistula [
Since no large series have been described, the surgical treatment should be proposed based on personal experience; there is no scientific evidence for the best surgical treatment.
From the systematic review of Antoniou et al. [
Most of the low grade leaks occur from a cystic duct or Luska’s and can be treated definitively by an endoscopic approach. The aim is to decrease the transpapillary pressure gradient; a good transpapillary bile flow allows for a reduction of the biliary loss from the leakage [
The stent is left in place for approximately four to six weeks and removed if ERCP shows the resolution of the leakage. The same approach can be used for minor lateral injuries of the right or common bile duct.
When surgery is necessary, it is usually undertaken to drain loculated collections rather than repair defects in the continuity of the biliary tree. In 10% of patients, bile leaks do not respond to sphincterotomy and/or plastic stent placement [
In the case of refractory bile leaks, we must keep in mind the possibility that the lesion is coming from transection of an anomalous aberrant right hepatic duct from which the cystic duct arose. Diagnosis may require MRCP; this lesion often required a surgical operation involving preferably a hepaticojejunostomy. Injuries to main common bile or common hepatic ducts are the most serious and are similar to the injuries most commonly seen in open cholecystectomy [
The authors declare that there is no conflict of interests regarding the publication of this paper.
The authors acknowledge the grant support provided by the Fondazione Romeo ed Enrica Invernizzi, Milano.