Benign biliary strictures and biliary fistulae

Fistulae involving the gallbladder

In Western countries, where cholesterol cholelithiasis abounds, the gallbladder is most often the site of severe inflammation and obstruction. Cholecystoenteric fistulae, an abnormal connection between the gallbladder and the enteric tract, constitute 70% to 85% of all biliary fistulae reported in the world literature. ^, Of these, 55% to 75% are cholecystoduodenal (gallbladder and duodenum), 15% to 30% are cholecystocolic (gallbladder and colon), and 2% to 5% are cholecystogastric (gallbladder and stomach) (see Fig. 42.1 ). Multiple fistulae (e.g., cholecystoduodenocolic) are very rare.

Gallstone ileus, the historical misnomer for distal ileal obstruction from gallstone impaction, is a dramatic clinical presentation of a cholecystoenteric fistula that is reported in 8% to 20% of large series of patients with biliary-enteric fistulae. ^{, ,} Modern series of bowel obstructions report gallstone ileus to be a very uncommon cause (well under 1%). ^,

Although most fistulae between the gallbladder and intestinal tract are obvious preoperatively or intraoperatively, cholecystocholedochal fistulae are insidious and may not be appreciated even at surgery. These biliobiliary fistulae develop between the gallbladder or cystic duct and the proximal common hepatic or common bile duct (CBD) (see Fig. 42.1D ). In either instance, the mechanism of formation is the same: pressure necrosis into the common duct by a large solitary impacted calculus. Recently, cholecystocholedochal fistula has been estimated to be present in 0.7% to 1.4% of biliary operations for calculous disease. Awareness of this condition is important and may help avoid damage to the common duct at operation.

Fistulae involving the common bile duct, cystic duct remnant, and other extrahepatic ducts

Choledochoduodenal fistulae are classified as either proximal or distal (see Fig. 42.1 E and 42.1 F). A proximal choledochoduodenal fistula is the most common form of abnormal communication between the CBD and adjacent structures (often the duodenum) and represents 4% to 20% of all biliary-enteric fistulae. In the past, the majority were caused by peptic ulcer erosion from the first portion of the duodenum into the proximal CBD. This cause is now much less common as a result of effective medical therapy for peptic ulcer disease. Other, less common causes of choledochoduodenal fistula include cholelithiasis, operative trauma, duodenal diverticula, echinococcal infection, and Crohn’s disease, as well as neoplasms of the stomach, distal bile duct, ampullary region, and duodenum.

Distal choledochoduodenal fistulae connect to the duodenum in the distal 2 cm of the CBD, and the fistula opening can be seen during percutaneous transhepatic cholangiography (PTC) (see Chapters 12 and 31 ) and endoscopic retrograde cholangiopancreatography (ERCP). The incidence of distal choledochoduodenal fistula secondary to cholelithiasis or operative trauma is variable in different parts of the world. With the development of radiologic studies of biliary anatomy, it is becoming apparent that many patients with biliodigestive complaints and gallstone disease may in fact have a distal choledochoduodenal fistula. A large series from Argentina reported the incidence of distal choledochoduodenal fistula to be 0.7%.

In Japan, where there is a high incidence of primary intrahepatic biliary tract calculous disease, Tanaka et al. reported a 5.3% incidence of parapapillary fistula in ERCP studies of 1500 patients. Ikeda et al. classified these as a type I fistula, characterized by a small fistula opening on the longitudinal fold of the duodenum just proximal to the papilla, probably caused by penetration of a small calculus through the intramural portion of the common duct into the duodenum; and type II fistula, a larger opening of the duodenum wall adjacent to the longitudinal fold, probably caused by a relatively large stone eroding from the extramural portion of a greatly dilated common duct into the duodenum.

Fistulae involving the intrahepatic ducts, liver, and lung

Thoracobiliary and bronchobiliary fistulae refer to communications between the biliary tree and the pleural cavity or bronchial tree, and are rare entities. The three major categories of bronchobiliary fistula are those resulting from (1) infection, (2) trauma, and (3) congenital causes. Worldwide, the most common cause of bronchobiliary fistula in adults is parasitic disease of the liver, either echinococcal (see Chapter 72 ) or amoebic disease (see Chapters 45 and 71 ). In developed countries, iatrogenic injury to the biliary system is the most frequent cause.

The hallmark symptom of a bronchobiliary fistula is bilioptysis, coughing up bile, in conjunction with other pulmonary complaints. Jaundice, cholangitis, and external biliary fistula or subphrenic abscess may also occur. Radiographic confirmation of the diagnosis is possible by a variety of methods. In the presence of an external fistula, injection of contrast solution is the most direct approach. PTC and ERCP are equally effective and have the potential for therapeutic intervention. Bronchobiliary fistulae also have been shown by cholescintigraphy. Computed tomography (CT) and magnetic resonance imaging cholangiopancreatography (MRCP) are also useful in assessing the upper abdomen and biliary tract but rarely visualize the fistula tract. ^,

The treatment of parasitic diseases of the liver is discussed elsewhere in this edition (see Chapters 45 , 71 , and 72 ). In large series of surgically treated cases of hepatic echinococcal disease in Greece and Turkey, only 2% were complicated by rupture into the lung or bronchi. Amoebic abscess of the liver has been reported in association with bronchobiliary fistula in 8% of cases. The successful treatment of these fistulae depends on the use of appropriate surgical drainage or resection in conjunction with appropriate pharmacologic therapy.

The incidence of bronchobiliary fistula as a consequence of surgical treatment for hepatobiliary tract neoplasm or calculi has decreased, as patients are operated on earlier in the course of their disease with better-established surgical techniques. ^, Reports of bronchobiliary fistula caused by liver tumor ablative therapies, such as radiofrequency ablation, have been described. These cases resolved with biliary drainage alone; however, there are two reported cases of successful treatment using drainage and pleurocentesis with α-cyanoacrylate glue. ^,

Untreated choledocholithiasis complicated by repeated episodes of biliary obstruction and cholangitis is another, albeit infrequent, cause of bronchobiliary fistula. Brem et al. reported the successful treatment of an 87-year-old patient with this clinical situation by endoscopic papillotomy alone. Bronchobiliary fistulae should be treated by transampullary biliary decompression to reduce the fistula tract pressure. Patients with a persistent fistula or infection may require transthoracic debridement and drainage.

Posttraumatic thoracobiliary fistulae are extremely rare (see Chapter 113 ). ^, Historically, successful treatment required pulmonary decortication, repair of the diaphragm, and adequate drainage above and below the diaphragm. More recent publications have described successful treatment through endoscopic decompression of the biliary system and pleural drainage. ^, Although the optimal management strategy remains undefined, reports suggest that aggressive surgical intervention should be reserved for cases that fail conservative management. ^,

Neuhauser et al. first described congenital bronchobiliary fistula in an infant with a tract communicating between the right main stem bronchus and the hepatic duct that passed through the posterior mediastinum. Tommasoni et al. described two newborn infants with this condition treated surgically. It has also been documented that there is a very high incidence (approximately 36%) of co-existing hypoplasia or biliary atresia and congenital diaphragmatic hernia. ^{, ,} There are several options for reestablishing communication with the intestinal tract, including Roux-en-Y choledochojejunostomy, fistula enteric anastomosis, and portoenterostomy in cases of extrahepatobiliary atresia (see Chapter 32 ). On microscopic examination, the proximal portion of the fistula in most patients resembles the bronchus, and the distal segment resembles the esophagus; the embryologic explanations for this anomaly are conjectural. ^, Transthoracic excision of the fistula with surgical correction of associated biliary anomaly is usually curative.

Computed tomography and magnetic resonance imaging cholangiopancreatography

CT and MRCP (see Chapter 16 ) are able to demonstrate gallstones, air in the biliary tree, the presence of additional stones, and a biliary-enteric fistula. ^, In the case of gallstone ileus, these studies are useful for estimating the size of an impacted stone and determining the site of intestinal obstruction for planning operative approaches ( Fig. 42.2 ). Newer multidetector CT scanners, which use three-dimensional volume-rendering reconstruction, are better able to estimate stone size as well as the presence of additional stones and may be able to detect an impacted stone before severe clinical symptoms are evident. Modern magnetic resonance imaging (MRI) and MRCP have been shown to accurately detect most small fistulous tracts. MRI scanning can also be used to show other important pathologic changes, such as distal common duct stones, other obstructive processes, the presence of a subphrenic abscess, pleural effusion, or parasitic disease of the liver. Scanning can also be used to verify and localize contrast extravasation after invasive cholangiography or after contrast injection of an existing controlled external fistula ( Fig. 42.3 ).

Direct cholangiography

Direct injection of contrast material is the best way to outline the normal and pathologic anatomy of the biliary tract (see Chapter 20 ). This imaging can be accomplished by ERCP, PTC, or through a fistulogram. Intraoperative cholangiograms are another method of directly imaging the biliary tree. Numerous reports have documented the efficacy of ERCP in demonstrating biliary fistulae. ^, Endoscopically, the alimentary side of a fistula near the ampulla of Vater can sometimes be cannulated to obtain a high-quality radiograph of the communicating biliary anatomy. ^{, ,} In fact, the largely unappreciated and frequently asymptomatic parapapillary choledochoduodenal fistula has been found to be quite common. ^{, , ,} There have been far fewer reports of the role of PTC in demonstrating biliary fistulae, but PTC can be helpful in the diagnosis and treatment of various types of biliary fistulae associated with dilated intrahepatic ducts.

Plain and contrast radiographs

Pneumobilia, the presence of air in the biliary tree, may be noted on plain films of 30% to 50% of patients with gallstone ileus ( Fig. 42.4 A). Other classic radiographic signs of gallstone ileus are visualization of a calcified gallstone in the abdominal cavity at a distance away from the gallbladder (see Fig. 42.4 B), serial imaging demonstrating migration of a previously observed calcification, and a change in the level of mechanical intestinal obstruction—the so-called “tumbling obstruction.” ^, However, only 30% of gallstones are sufficiently calcified to be radiopaque.

A barium meal or upper gastrointestinal (GI) series shows reflux of contrast material into the fistula in 40% of cholecystoduodenal communications and 75% of choledochoduodenal fistulae of peptic ulcer origin. ^, If the plain film and barium swallow are used in concert, more than 60% of biliary enteric fistulae are correctly diagnosed preoperatively ( Fig. 42.5 ). Barium enema demonstrates greater than 95% of cholecystocolic fistulae ( Fig. 42.6 ).

Sonography

Sonography is a useful noninvasive diagnostic aid in the preoperative evaluation of a patient with a suspected biliary fistula (see Chapter 16 ). Although a radionuclide scan may readily show a fistula, a sonogram can assess for the presence of calculi in the gallbladder; common duct stones; and inflammatory, cystic, or infiltrative disease of the liver and pancreas. Sonography can be useful to detect pneumobilia, indicating a high likelihood of a biliary-enteric fistula. In gallstone ileus, sonography can detect an ileal stone not seen on plain films. Ripollés et al. reported that 22 of 23 patients who had undergone surgery for gallstone ileus were found on sonogram to have pneumobilia. In contrast, Lassandro et al. were able to identify pneumobilia in 56% of their 27 patients and often required additional investigation to characterize the obstruction. Sonography is also useful to document the persistence or closure of biliary enteric fistulae after initial emergent surgical or combined endoscopic lithotripter treatment of gallstone ileus, and it has aided the decision for or against further surgery.

Laboratory testing

Serum liver function tests, electrolytes, and blood counts are useful in the comprehensive evaluation and management of a patient with a symptomatic biliary fistula. Sputum analysis for bilirubin and viable scolices or membranes can be used as laboratory evidence to establish the diagnosis of bronchobiliary fistulae secondary to echinococcosis.

Radionuclide imaging

Radionuclide scans with imidoacetic acid agents bound to technetium ( p -isopropylacetanilido iminodiacetic acid [PIPIDA] and hepatobiliary iminodiacetic acid [HIDA]) have become an effective method of assessing normal and pathologic anatomy of the extrahepatic bile passages (see Chapter 18 ). Prolonged (24 hours) accumulation of radioactivity, measured by scanning or quantitative isotopic counts of body secretions (e.g., sputum), has been used to demonstrate small or intermittent fistulae from the biliary tract to the respiratory passages and the colon. ^{, , ,}

Gallstone ileus

Gallstone ileus is the blockage of the intestinal tract by a gallstone large enough to occlude its lumen partially or completely (see Chapter 33 ). Often, the site of obstruction is the distal ileum. This rare presentation of intestinal obstruction is too indelibly fixed in the medical imagination to permit amendment of the inappropriate term ileus; perhaps this derives from the frequent initial clinical impression of an unexplained ileus, in that many patients with gallstone obstruction are initially seen without any clinical history or physical signs to suggest mechanical intestinal obstruction. Similar to other patients in Western Europe and English-speaking countries, where cholesterol cholelithiasis predominates, patients seen with this manifestation of advanced biliary tract disease are usually elderly, female, and beset by multiple other medical conditions that may delay or complicate prompt diagnosis and appropriate treatment.

When an elderly person presents with typical signs and symptoms of intestinal obstruction or, perhaps less dramatically, an unexplained ileus without an obvious cause, gallstone ileus should be considered. Approximately half of patients presenting with gallstone ileus describe a history suggesting prior calculous biliary tract disease. At the time of clinical presentation, however, signs of active gallstone disease, cholangitis, and jaundice may be absent. Laboratory data are consistent with fluid and electrolyte disturbances related to intestinal obstruction. Some abnormalities of liver function tests (LFTs) may suggest chronic disease of the liver and biliary tract in approximately one quarter of patients.

The classic plain abdominal film triad of small bowel obstruction, pneumobilia, and ectopic gallstone is considered pathognomonic of gallstone ileus; however, the triad is encountered in only 30% to 35% of cases. Pneumobilia is often not appreciated even in retrospect. If biliary-enteric fistula is suspected and a barium meal is administered, reflux of barium into the biliary tree yields a correct preoperative diagnosis in 60% of patients (see Fig. 42.5 ). Calculi large enough to obstruct the intestine usually do so in the last 50 cm of ileum, although sometimes also in the jejunum or duodenum and rarely in the sigmoid colon. Such calculi are usually larger than 2.5 cm, although smaller stones may increase in size via accretion as they descend through the GI tract. If partially calcified, these stones are readily apparent on plain radiographs (see Fig. 42.2 B).

Abdominal ultrasound, as mentioned earlier, may establish the diagnosis of gallstone ileus or provides other information relevant to the diagnosis, ^{, , , ,} revealing pneumobilia, the site of the fistula, additional stones in the gallbladder or in the common duct, and occasionally the location of an ectopic calculus. The diagnostic superiority of CT over abdominal plain films and sonography for gallstone ileus is now well established. ^{, , ,} In fact, the clinical significance of Rigler’s triad has been revitalized by CT because all three findings are more consistently detected (∼78%) by this method. ^,

The clinical presentation of gallstone ileus has not changed. In patients with intestinal obstruction, preoperative diagnostic accuracy is approximately 75%. Preoperative diagnostic accuracy has contributed to an improved outcome of therapy. The frequent use of CT in patients with symptoms of intestinal obstruction has led to additional improvement in the diagnostic accuracy of gallstone ileus and has resulted in a decrease in the high mortality rate encountered with this disease. ^{, , ,}

The overriding consideration in patients presenting with gallstone obstruction of the intestine should be relief of the life-threatening cause of obstruction (i.e., enterolithotomy). This surgical emergency should be approached expeditiously and without a period of waiting in the hope that a suspected stone will pass; it will not. The only reason for delay should be to provide adequate preoperative fluid and electrolyte resuscitation to these critically ill patients and, if possible, to assess the presence of other gallstones in the gallbladder and common duct by means of sonography or MRCP. The use of nasogastric decompression and preoperative antibiotics is recommended to minimize the risks of aspiration and postoperative wound infection.

Unless the obstructed segment is ischemic or has perforated and requires a small bowel resection, the obstructing calculus can be manipulated proximally to a healthy section of bowel, where a safe enterotomy and stone removal may be executed. Jejunal impaction, often by stones larger than 4 cm, occurs approximately 15% of the time, and enterotomy may be made at the site or just proximal to it. Duodenal obstruction, usually in the bulb, is known as Bouveret syndrome , which occurs in 10% of patients and may be handled by duodenostomy or pyloroplasty. It occasionally may be possible to manipulate the stone back into the stomach and remove it via gastrotomy. Rarely, a gastroenterostomy or duodenal exclusion procedure is necessary to protect a severely traumatized duodenum at the site of impaction.

Bouveret syndrome and other cases of gallstone impaction high in the jejunum have also been managed successfully by a combination of endoscopy and electrohydraulic lithotripsy. However, a review of 128 cases by Cappell et al. noted marginal success with endoscopy. We are aware of one case report of a failed endoscopic extraction that led to spontaneous uneventful passage of the stone. In rare instances, the sigmoid colon is the site of obstruction of a calculus that has managed to pass through the terminal ileum or enter the colon via a cholecystocolic fistula. ^, Almost invariably, some other pathologic process, such as diverticulitis, has produced an area of colonic narrowing. An early report by Milsom et al. suggested that surgical management should include colostomy to decompress the proximal bowel and Hartmann closure of the distal bowel if the impacted stone cannot be manipulated to a transverse colostomy. However, reports have described successful management with enterolithotomy and resection of the fistulous segment. Colostomy with Hartmann’s pouch was reported in a case of sigmoid perforation with purulent-free abdominal fluid due to an impacted gallstone in an elderly patient.

Open exploration and enterolithotomy has been the standard surgical approach for the treatment of classic gallstone ileus. It not only allows removal of the obstructing stone but also permits careful palpation of the entire bowel and gallbladder region, to determine whether other gallstones are in transit more proximally or if any still reside in the diseased gallbladder (see Fig. 42.2 B). These calculi may be poised for passage through the fistula, possibly to induce a recurrent episode of gallstone ileus, a phenomenon estimated to occur in 5% of cases. ^{, ,} Several authors have described laparoscopic or laparoscopic-assisted treatment for patients with gallstone ileus. Yu et al. reported on 34 cases of gallstone ileus treated laparoscopically with satisfactory results. Although the global experience with laparoscopic management of gallstone ileus is growing, the existing literature is based entirely on small numbers of patients and case reports. Because of these limitations, the efficacy and safety of this approach remain unclear, although the available reports suggest favorable outcomes in selected patients.

There is considerable debate in the surgical literature as to whether cholecystectomy, common duct exploration, and/or dismantling and closure of the cholecystenteric fistula should accompany enterotomy and relief of the obstruction or await a second operation. ^{, ,} Historical data of published reports showed a lower mortality rate of 11.7% in the enterolithotomy-alone group compared with 16.7% for patients who underwent a one-stage operation. Several published reports indicated that operative mortality is lower in these critically ill, elderly patients when only the gallstone obstruction is relieved. ^{, , , ,} This has led to the general agreement that enterolithotomy alone should be done for fragile patients with significant comorbidities and that the single-stage procedure should be reserved for young, fit, and low-risk patients. However, data from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database have challenged this conservative approach. Mallipeddi et al. evaluated 127 cases of gallstone ileus and noted a 6% 30-day mortality and 35% morbidity rate; 14 patients underwent cholecystectomy at the time of index operation. Interestingly, there was no significant difference between the two cohorts with regard to age, comorbid conditions, preoperative sepsis, classification as an emergent procedure, or differences in morbidity or mortality rates. Taken together, this report suggests that cholecystectomy and enterolithotomy may be safer than historically reported. ^, We recommend maintaining a conservative approach in such patients and would only consider cholecystectomy in the clinically stable patient. Indeed, careful follow-up of patients treated with enterolithotomy alone indicates that one third to one half will have minimal or no symptoms after relief of the gallstone ileus, and no further treatment will be necessary. ^{, ,} It is important to remember that recurrence of gallstone ileus in patients treated with enterolithotomy alone is estimated to be between 5% and 10%. ^, Common duct stones are found in 40% of patients with biliary-enteric fistula; thus it is likely that patients who continue to be symptomatic will require endoscopic or open surgical removal of their common duct stones in addition to cholecystectomy and repair of the fistula. As mentioned, operative mortality rates were reported at 15% to 25% in large reported series until the early 1970s. Reductions in operative mortality rates have been possible by limiting treatment to enterotomy and stone removal alone without further surgical therapy in high-risk patients. ^{, , , ,}

Cholecystoduodenal fistulae

Most cholecystoduodenal fistulae do not result in gallstone ileus (see Fig. 42.1 A). Rather they are typically asymptomatic or occur in association with common digestive complaints consistent with gastric or biliary tract disease. They may be found during an upper GI barium study or at the time of abdominal surgery for an unrelated problem.

If an asymptomatic or mildly symptomatic cholecystoenteric fistula is diagnosed preoperatively, many of the management decisions regarding gallstone ileus discussed previously may apply. Elective surgery may never be necessary in a completely asymptomatic individual, and surgery may present an unfavorable risk-to-benefit ratio in an elderly, minimally symptomatic patient. Along with dismantling of the fistula and management of common duct stones, other alternatives to cholecystectomy should be considered, such as a period of expectant management with careful observation, endoscopic papillotomy and stone extraction (in the case of common duct stones) with the gallbladder left in situ, or interval cholecystectomy if symptoms of pain or cholangitis persist after endoscopic biliary surgery. In a relatively healthy patient, we believe that cholecystectomy, closure of the fistula, and treatment of any common duct pathology promise the best long-term therapeutic result. ^,

If an incidental cholecystoduodenal fistula is discovered at the time of surgery, the major intraoperative decision revolves around the patient’s need for, and ability to tolerate, additional surgical manipulations. If the patient is judged an unsound risk, or if the biliary tract pathology is not believed to be pertinent to the major indication for operation, observation alone should be considered. One operative consideration is to perform a cholecystostomy and extraction of large calculi, which should add little additional risk. Usually, the gallbladder is shrunken, barely palpable, and stuck to the duodenum. If one is going to proceed with definitive cholecystectomy and closure of the fistula, consideration should be given to performing an operative cholangiogram to rule out common duct stones.

Cholecystocolic fistulae and choleric enteropathy

A cholecystocolic fistula may develop acutely in patients with long-standing mild or moderately symptomatic biliary tract disease and may be heralded by a sudden change in bowel habits with multiple, loose stools and the development of fever, chills, and other signs of cholangitis from colonic bacterial reflux into the biliary tract. There is a female predominance with approximately a 3:1 ratio. Many patients either weather or ignore these symptoms without seeking medical attention, and some develop signs and symptoms that may incriminate the entire GI tract. Increased stool frequency persists, particularly after ingestion of food, and bouts of fever and malaise subside. Other characteristic symptoms then appear, such as eructation, nausea, weight loss, and increasing diarrhea and steatorrhea. These latter symptoms precede the onset of choleric enteropathy, a dramatic complication of cholecystocolonic fistula. This enteropathy also is seen in other major disturbances of bile acid metabolism, such as with major ileal resection or blind loop syndrome.

Choleric enteropathy comprises a wide spectrum of anatomic, physiologic, and biochemical changes produced by a significant alteration of the enterohepatic circulation. The malabsorption syndrome secondary to cholecystocolonic fistula was clinically documented first by Augur and Gracie and has since been studied by others. ^, Ordinarily, 95% of bile acids are passed down the jejunum, aiding in fat and cholesterol absorption, before being largely reabsorbed in the terminal ileum as part of an efficient enterohepatic circulation. Two or three cycles of the bile acid pool per meal occur, with further metabolism of bile acids in the colon and very little lost. With a cholecystocolic fistula, however, a large part of all of the primary bile acid pool is lost directly into the colon, resulting in a high luminal concentration of bile acids. In the colon, the primary bile acids undergo deconjugation and dehydroxylation by fecal bacteria, and this increased concentration of bile acids induces a water secretory diarrhea.

Depending on the amount of bile still passing via the common duct into the small bowel, fat absorption is affected, which over time may result in fatty-acid diarrhea. More immediately, however, colonic secretion of water and electrolytes is maximally stimulated by bile acids. At this point, even with a partial shunt to the colon, the bile acid concentration still normally passing down the common duct and through the small intestine may be too small to effect micellar solubilization of dietary fat. Until the fistula is dismantled, massive shunting of bile acids to the intestine persists and promotes continued watery diarrhea, diminished bile salt pool, and a variable degree of fat malabsorption.

Cholangitis (see Chapter 43 ) seems to be a more prominent feature of cholecystocolic fistula compared with other biliary-enteric fistulae. This may be related to a narrow fistula that is prone to intermittent obstruction. ^{, ,} We are also aware of one case report of a patient with a cholecystocolic fistula who presented with massive lower GI hemorrhage. Given the higher likelihood of cholangitis, serum levels of bilirubin, alanine aminotransferase, and γ-glutamyltransferase may be slightly elevated at presentation.

Because of the unusual initial complaints, a full investigation for malabsorption, which includes upper GI studies, GI sonography, and jejunal biopsy, may be undertaken but usually does not clarify the diagnosis. A pathognomonic triad consisting of pneumobilia, chronic diarrhea, and vitamin K malabsorption was recently suggested by Savvidou et al. to aid in the diagnosis of cholecystocolic fistula. Although the condition of bile acid malabsorption can be diagnosed by the selenium-75-homocholic acid taurine (SeHCAT) test, this study is time consuming and is not widely available. Plain abdominal radiographs have been reported to reveal air in the biliary tree in only 50% of cases. The diagnosis is most readily made by a barium enema (see Fig. 42.6 ) demonstrating air and contrast in the gallbladder and bile ducts. Failure of a barium enema to show a cholecystocolic fistula has been reported, but this is rare. In such cases, the cholecystocolic fistula can be diagnosed by ERCP.

There is little controversy about the appropriate treatment for cholecystocolic fistulae. Except in the most extenuating circumstances, the fistulae should be dismantled because of the risk of sepsis and previously mentioned metabolic disturbances. Cholecystectomy and, if indicated, common duct exploration should be performed at the same time. Laparoscopic surgical treatment of cholecystocolic fistulae has been reported. ^{, , , ,} Preoperative imaging of the CBD and treatment of CBD stones, if present, is mandated in all cases of cholecystocolic fistulae.

Cholecystocholedochal fistula, including Mirizzi syndrome

The pathogenesis of cholecystobiliary fistula is similar to the mechanism of fistula formation between the gallbladder and other adjacent segments of the alimentary tract: The offending calculus remains impacted in the ampulla of the gallbladder or cystic duct, and the resultant inflammation causes adherence and then perforation into the adjacent structure (see Fig. 42.1 D). In 1948 Mirizzi described the clinical picture in detail and called it functional hepatic syndrome. It is now commonly referred to as Mirizzi syndrome . The mechanism of jaundice was postulated by Mirizzi to be due to spasm of the hepatic sphincter secondary to inflammation in the region of the cystic duct junction with the common hepatic duct; however, extensive histologic studies have failed to disclose a “sphincter” in the common hepatic duct. The large size of the stone and the acute cholecystitis with marked pressure necrosis and inflammatory reaction at the site of stone intrusion into the common hepatic duct combine to produce jaundice with variable components of extrinsic compression and intrinsic calculous blockage of bile flow.

The early phase of a cholecystobiliary fistula presumably exists when a large gallstone is impacted in the ampulla of the gallbladder or in the intramural segment of the cystic duct, which often courses parallel to the common duct. The jaundice that occurs as a consequence of this pathologic anatomy is clinically indistinguishable from choledocholithiasis. McSherry et al. suggested that this classic picture ( Fig. 42.7 ) of Mirizzi’s “functional hepatic syndrome” be subclassified as type 1. With progression of the disease, extrusion of the stone into the common hepatic duct may occur, and a fistula forms between the gallbladder and the hepatic duct. This is classified as type 2 (see Fig. 42.1D ), which is characteristically diagnosed intraoperatively by observing a “gush” of bile on removal of the impacted stone. Csendes et al. further subclassified type 2 patients into three categories based on the percentage of the wall of the common duct that was eroded by the calculus. In this subclassification, type II is a fistula involving less than one third of the circumference of the bile duct, type III involves two thirds, and type IV is a fistula with complete bile duct destruction. This classification scheme was recently updated to include a type V, which describes cholecystoenteric fistula, with or without gallstone ileus, co-existing with any of the other types.

The classic findings on ultrasonography include dilation of the biliary tree proximal to the gallbladder neck, a stone impacted in the gallbladder, and an abrupt change in the caliber of the common duct below the stone. Because most of these patients present with jaundice or abnormal LFTs, a preoperative ERCP or PTC frequently is performed. These imaging studies permit a precise delineation of the condition, assisting with surgical strategy.

Historically, biliobiliary fistulae have been referred to as a “trap” in the surgery of cholelithiasis. This term is appropriate because the presence of such a fistula frequently is not recognized until the time of surgery, often not soon enough to prevent injury to the common duct in an attempt to dissect the ampulla of the gallbladder or the cystic duct. Lygidakis et al. emphasized the technical problems in operating on these patients. Other authors emphasized the importance of preoperative direct cholangiography. In patients with jaundice, biliary drainage may be necessary in the preoperative management. The endoluminal biliary stent can be palpated during surgery and used for orientation to the biliary anatomy. In these cases, the acute inflammation is often intense, resulting in severely distorted hilar anatomy. The hepatoduodenal ligament is often “accordioned” or tethered to the base of the liver, making recognition of the CBD difficult. Although some centers are increasingly advocating a minimally invasive approach, we manage these patients by an open technique. For the Mirizzi type 1, our practice is to perform a near-total cholecystectomy leaving the biliary stent in place, if present, throughout the postoperative recovery until the inflammation subsides. For Mirizzi type 2, direct choledochotomy with removal of the stone, followed by direct closure of the gallbladder, may be performed. Alternatively, the opened gallbladder may be anastomosed to the duodenum or a Roux-en-Y loop of jejunum. ^{, ,} It is important to emphasize that stenosis of the biliary tree typically resolves spontaneously in the postoperative period, and choledochotomy is seldom indicated.

A minimally invasive approach to the management of patients with Mirizzi syndrome can be undertaken. ^{, ,} To address the utility of laparoscopic treatment of Mirizzi syndrome, Antoniou et al. conducted a systematic review of the literature on this topic. Because of the strict study criteria, the authors identified only 10 of 66 articles for analysis. The total number of patients treated by laparoscopy was 124, of which 73 (59%) were successfully completed. Interestingly, patients from studies reporting a high preoperative diagnosis rate (>80%) had a significantly lower risk for conversion. The main reasons for conversion included technical failure as a result of dense adhesions in the triangle of Calot, unclear anatomy, and unsuccessful stone retrieval. The analysis showed a complication rate of 16%, with residual stones and bile duct injury the most common complications. The authors concluded that laparoscopic treatment of Mirizzi syndrome cannot be recommended as a standard procedure because of the high failure rate and hazard posed by dissection in this area. ^{, ,} However, greater advances with advanced laparoscopy and endoscopy may offer newer treatment paradigms that preserve patient safety and afford acceptable outcomes. A study by Yuan et al. described 49 patients with type II Mirizzi syndrome successfully managed by laparoscopic subtotal cholecystectomy with ERCP, without need for conversion to open approach, with minimal morbidity, and with reduced postoperative complications compared with a group treated by purely open approach. An approach with combined endoscopic and robotic subtotal cholecystectomy is described by Lee et al. ^, Recent reviews on management advocate for careful patient selection, and for combined minimally invasive/endoscopic approaches for type I and II Mirizzi syndrome to be performed with proper surgical and endoscopic expertise. ^,

Proximal choledochoduodenal fistulae and chronic peptic ulcer disease

Chronic duodenal ulcer can cause inflammation and fibrosis in the entire periampullary area and result in a distal biliary stricture or proximal choledochoduodenal fistulae. Patients may be asymptomatic, or they may present with jaundice and cholangitis in a patient with a long history of duodenal ulcer (see Fig. 42.1E ). Biliary tract symptoms are usually absent, and these patients generally do not have associated cholelithiasis. The diagnosis may be suggested by pneumobilia in 15% to 60% of patients. More often, the diagnosis is made as contrast material from an upper GI study refluxes up the common duct to outline a normal gallbladder. Endoscopy with direct visualization of the ulcer and fistula and ERCP are the best studies to confirm the diagnosis and evaluate the extent of disease.

Given the paucity of reported experience with choledochoduodenal fistula, it is not surprising that, until recently, treatment recommendations have been controversial. ^{, , ,} Most authors now agree that treatment should be directed at the ulcer diathesis and not at the biliary tract or the fistula itself. Medical management with proton-pump inhibitors and therapy for Helicobacter pylori is often sufficient to control the ulcer disease and even result in closure of the fistula.

Modern success rates of medical management for peptic ulcer disease have resulted in a drastic reduction in the number of case reports of patients with proximal choledochoduodenal fistulae. Although choledochoduodenal fistula because of peptic ulcer is now rare, clinicians should remain aware of this clinical entity, especially in symptomatic patients with refractory peptic ulcer disease. In such patients, surgery may be indicated to prevent major complications. If indicated, an exclusion type of gastric resection or duodenal bypass procedure, such as a Billroth II gastrectomy or gastroenterostomy, should be performed in addition to a vagotomy. There is no need to close the fistula and doing so may injure the duodenum or bile duct. Cholecystectomy and biliary enteric reconstruction may be done, but these are reserved for cases of biliary stricture. It should be stressed that in modern times these operations are rarely necessary.

Distal parapapillary choledochoduodenal fistula

Whether caused by spontaneous gallstone erosion or by iatrogenic damage to the distal common duct, parapapillary fistulae have a clinical presentation similar to that of other advanced calculous biliary tract diseases. In the series reported by Tanaka in 1983, the following observations were made: a history of biliary symptoms longer than 10 years’ duration in 46%; pain and/or jaundice in 88% and 69%, respectively; prior biliary surgery in 54%; air or barium in the biliary tree in 41%; cholelithiasis in 71%; and choledocholithiasis in 38%. Additionally, there are more recent case reports of fistulae in patients who present with biliary tumors and who have no prior history of gallstone disease but a history of endoscopic or surgical biliary manipulation. Chronic reflux of bilious material and biliary stasis are thought to precede obstructive biliary tumors that may lead to parapapillary choledochoduodenal fistula. ^, The anatomic diagnosis rests on meticulous endoscopic observation and expertise in the technique of ERCP ( Fig. 42.8 ; also see Fig. 42.1F ).

The management of these biliary fistulae is still evolving, and a variety of endoscopic techniques have been advocated. ^, These techniques involve using endoscopic sphincterotomy to widen the choledochal fistula enough to permit free drainage or to create a common channel between the fistula and natural ampullary orifice. When necessary, open surgical procedures, such as hepaticodochojejunostomy, have been used.

Fistula to the hepatic veins or portal veins

Biliary-venous fistula is a rare occurrence that results in bilhemia (see Chapter 116 ), a condition associated with high biliary pressures and flow of bile into the systemic circulation via hepatic/portal veins. This can be dangerous, especially if there is related biliary infection, which can result in systemic sepsis. This fistula can also be associated with interventional transhepatic maneuvers. Case reports describe portobiliary fistula after ERCP. ^, When a large-caliber intrahepatic bile duct is injured during the creation of a transjugular intrahepatic portosystemic stent-shunt, this may be complicated by a biliary-venous fistula. The resulting biliary leak plays an important role in the subsequent risk of stenosis and occlusion of the portosystemic shunt.

Fistula after cholecystostomy tube or other radiologic procedures

Percutaneous cholecystostomy is the percutaneous placement of a catheter into the lumen of the gallbladder (see Chapter 35 ). This procedure only requires local anesthesia and can be performed under ultrasound guidance at the bedside of critically ill patients. Typically, the catheter is allowed to drain externally to treat underlying infection in an obstructed gallbladder. Persistently elevated cholecystostomy tube drainage or cutaneous drainage of biliary contents after cholecystostomy tube removal may indicate ongoing obstruction in the cystic duct or distally in the common bile duct ( Fig. 42.9 ). A case report by Lofgren et al. describes discovery of an external biliary fistula after cholecystostomy tube removal after a large abdominal wall abscess developed, which was treated by incision and drainage and subsequent cholecystectomy. A retrospective study by Peters et al. found rates of fistula and abscess after percutaneous cholecystostomy tube placement to be 3.6% and 1.8%, respectively.

Biliary fistulae may follow any invasive radiologic procedure involving the hepatobiliary system and are usually the consequence of ongoing distal biliary obstruction. Published rates of clinically significant biliary leak after interventional radiologic procedures vary significantly and depend on patient selection and practitioner experience. Complications result from suboptimal puncture location, incorrect selection of biliary catheter size, and inadequate postprocedural tube care. Burke et al. classified bile leakage, sepsis, and infected biloma as major complications that occur at rates of 2% after PTC and biliary drainage procedures (see Fig. 42.4 ).