Cholecystolithiasis and stones in the common bile duct: Which approach and when?

Transabdominal ultrasound

Transabdominal US is the diagnostic test of choice in evaluating patients with right upper quadrant (RUQ) abdominal pain thought to be related to biliary pathology (see Chapter 16 ). It can readily identify cholelithiasis and signs of gallbladder inflammation and is an appropriate initial modality in the evaluation of CBD stones. US can identify bile duct dilation because of stone obstruction, and it can visualize the actual stone in some cases (sensitivity 0.3, specificity 1.0). If the extrahepatic bile duct diameter is less than 5 mm, CBD stones are exceedingly rare, whereas a diameter greater than 10 mm with signs of jaundice predicts the presence of CBD stones in more than 90% of cases. Axial computed tomography (CT) scans have better sensitivity (84%) for choledocholithiasis than US. Helical CT scans outperform conventional nonhelical CT, with 88% sensitivity and 73% to 97% specificity. In terms of availability, cost, and radiation exposure, US prevails as the first-line diagnostic.

Magnetic resonance cholangiopancreatography

MRCP is the most accurate noninvasive modality available (see Chapter 16 ). It is useful as an adjunct when a definitive diagnosis is not readily apparent on US. MRCP is the standard investigation for CBD stones for patients with intermediate probability or for those who need to be investigated to exclude other differential diagnoses. MRCP is especially helpful when anatomic considerations preclude ERCP (status post–Billroth II gastrectomy, Roux-en-Y biliary bypass, duodenal stenoses). The drawback of MRCP is its high cost, which challenges its routine use as a more front-line diagnostic modality.

Endoscopic retrograde cholangiopancreatography

ERCP is still considered the gold standard diagnostic modality, although it is invasive, requires radiation, and has significant complications (see Chapters 20 and 30 ). Observed complications after ERCP include pancreatitis, hemorrhage, cholangitis, perforation, and a clinically relevant mortality rate. Routine ERCP before all laparoscopic cholecystectomies is impractical and unnecessary and should be reserved for patients with high pretest probability of or known choledocholithiasis. When overused, most cholangiograms are normal, and costs and complication rates are prohibitive. Even in patients at high risk, namely those with jaundice, cholestatic LFTs, CBD dilation, and a history of pancreatitis, half will not have CBD stones at the time of ERCP. The utility of ERCP now lies more with its therapeutic capabilities rather than for diagnostic purposes.

Endoscopic ultrasound

EUS is very sensitive for choledocholithiasis, and a meta-analysis reveals that EUS can reduce unnecessary diagnostic ERCP (see Chapter 22 ). A systematic review reveals that patients who undergo EUS can avoid ERCP in 67% of cases, with fewer complications and less pancreatitis compared with those undergoing ERCP initially. The diagnostic efficacy of EUS and MRCP compared with ERCP have revealed the tests to be quite comparable. ^,

Intraoperative cholangiography

IOC during cholecystectomy can accurately diagnose CBD stones and both minimize and maximize the need for ERCP (see Chapter 24 ). It is best used for intermediate-risk patients. The technique can be performed safely in both open and laparoscopic approaches. Surgeons can respond to such findings, flushing the duct to clear stones or debris. Open and laparoscopic IOC can successfully be completed in about 95% of patients, with sensitivity for detecting CBD stones between 80% and 92% and specificity of 93% to 97%. Regardless, an ongoing debate remains whether IOC should be performed routinely or selectively during cholecystectomy. When used routinely, it has high sensitivity and specificity both for suspected CBD stones and for the 3% to 4% of stones that are not clinically suspected but may become symptomatic postoperatively. Other suggested benefits specifically relate to the prevention of bile duct injuries. The randomized trials that have been performed to address this question are small, and even a systematic review of these trials was not sufficiently powered to demonstrate a significant benefit. Because no large prospective randomized trial has answered the question of whether routine IOC is beneficial, most practicing surgeons perform IOC selectively.

Asymptomatic gallstones

Gallstones are one of the most common pathologies affecting the general population. From 10% to 20% of the Western population has gallstones, and the majority of patients with gallstones, about 65% to 80%, are asymptomatic. Studies of the natural history of silent gallstones have shown that symptoms develop in 1% to 2% of patients per year (see Chapter 33 ). Among patients with asymptomatic gallstones, about 10% develop symptoms in 5 years, and about 20% develop symptoms by 20 years. Importantly, most patients experience symptoms before the development of a complication. Therefore the majority of patients with asymptomatic gallstones can be observed, and surgical intervention (laparoscopic cholecystectomy) should be offered only when symptoms develop.

There are certain groups for which prophylactic cholecystectomy has previously been recommended for asymptomatic gallstones. This is an area of controversy, however, and the recommendations are changing. These populations include solid-organ transplant patients; patients with diabetes; patients with chronic liver disease, sickle cell anemia, or other chronic hemolytic anemias; patients undergoing bariatric or other gastrointestinal (GI) operations; and those with a potentially increased risk of gallbladder carcinoma ( Table 38.1 ).

Prophylactic cholecystectomy for asymptomatic cholelithiasis was previously recommended for patients with diabetes mellitus. Studies in the late 1960s reported a higher mortality after emergency cholecystectomy in patients with diabetes; however, subsequent meta-analysis revealed that diabetes was not an independent variable. Rather, associated risk factors such as cardiovascular, peripheral vascular, cerebrovascular, or prerenal azotemia were associated with more severe acute cholecystitis. ^, More recent series have shown similar complication rates for acute cholecystectomy among diabetic and nondiabetic patients. Patients with diabetes with asymptomatic gallstones today are managed expectantly.

The incidence of gallstones is twice as high in patients with chronic liver disease. Most of these patients remain asymptomatic. Operative morbidity and mortality rates for patients with chronic liver disease are also significantly higher (see Chapter 75 ). Meta-analyses report no increase in mortality in asymptomatic patients with an expectant management approach. ^, Although laparoscopic cholecystectomy has been shown to be safe in well-selected Child-Pugh class A and B cirrhotic patients, it is contraindicated in all but emergent settings in Child-Pugh class C patients because of high complication rates.

Because of the association between morbid obesity and cholelithiasis, a high proportion of patients undergoing bariatric surgery have gallbladder pathology. Patients undergoing bariatric surgery have a higher incidence of cholelithiasis, related both to obesity and rapid weight loss. Studies report a cholelithiasis incidence of 27% to 35% before bariatric operations and a 28% to 71% increase in gallstone formation after bariatric surgery. Some surgeons use bile salt medications during periods of rapid weight change to help prevent cholesterol gallstone formation; however, more recent studies have shown that this approach is not cost-effective. The question of whether or not to perform concomitant cholecystectomy at the time of bariatric surgery is controversial, but an increasing number of studies suggest that prophylactic cholecystectomy in the absence of symptoms is not indicated. ^, In the case of gallstone formation after bariatric surgery without concomitant cholecystectomy, management should be expectant because the majority of patients remain asymptomatic. For patients with symptomatic cholelithiasis and concomitant morbid obesity, elective cholecystectomy is indicated. Some favor directed referral for cholecystectomy to bariatric surgical specialists, given their technical experience and enhanced facilities and equipment for the care of such patients.

Several factors must be considered for potential solid-organ transplant patients with asymptomatic cholelithiasis. In these patients, cholelithiasis is common, immunosuppression may increase infectious morbidity, and morbidity and mortality may be increased with emergency surgery. This problem was examined with decision analysis, using probabilities and outcomes derived from a pooled analysis of published studies. For pancreas and kidney transplant patients with asymptomatic cholelithiasis, however, expectant management was recommended, an approach that is widely agreed upon in the literature. Kao and colleagues recommended prophylactic after transplantation cholecystectomy for cardiac transplant recipients with asymptomatic cholelithiasis, an approach advocated by other studies as well because of the increased morbidity and mortality that has been demonstrated with subsequent urgent or emergent cholecystectomy compared with the general populace. This remains an area of debate, however, because other studies have demonstrated that expectant management of asymptomatic gallstones is safe.

Asymptomatic gallstones found at an unrelated open GI operation should prompt a cholecystectomy, if exposure is adequate and if the operation can be done safely. Studies of expectant management for patients with asymptomatic gallstones undergoing laparotomy for other conditions have shown a high (up to 70%) incidence of symptoms and/or complications from the biliary system, and a significant percentage (up to 40%) of patients require a cholecystectomy within 1 year of the initial operation. Further, no increase in morbidity is associated with concomitant cholecystectomy. ^,

The management of patients with asymptomatic gallstones undergoing abdominal aortic aneurysm (AAA) repair has evolved, especially with the advent of endovascular aortic procedures. In the past, when AAA repair and cholecystectomy were open operations, concomitant cholecystectomy was recommended to prevent the higher morbidity associated with the development of acute cholecystitis in the postoperative period. Studies reported no increase in graft infection or morbidity when cholecystectomy was performed after closure of the retroperitoneum; however, more recent data show similar mortality rates with or without concomitant cholecystectomy. Current management is typically expectant, and laparoscopic cholecystectomy can be performed after AAA repair without increased morbidity if symptoms develop. Although simultaneous laparoscopic cholecystectomy and endovascular AAA repair has been reported, ^, it is not widely practiced and certainly not for asymptomatic gallstones.

Children with asymptomatic gallstones fall into two main etiologic groups: those with hemolytic anemia (sickle cell disease, β-thalassemia, hemoglobinopathies) and those whose cholelithiasis stems from some other cause (total parenteral nutrition, short bowel syndrome, cardiac surgery, leukemia, lymphoma). Expectant management for children with hemolytic anemia is associated with a significant increase in morbidity and postoperative hospital stay, and elective cholecystectomy is therefore recommended. For patients with sickle cell disease and asymptomatic gallstones, elective cholecystectomy is advised because expectant management yields more than a 2-fold increase in morbidity. Further, the diagnosis of acute cholecystitis can be difficult to differentiate from acute vaso-occlusive sickle cell crisis. There is also a high incidence of choledocholithiasis in this population, and studies have demonstrated that ERCP can be safely used in children to perform sphincterotomy and stone extraction. In contrast, children with asymptomatic gallstones caused by other etiologies can be safely managed expectantly, and these gallstones have been shown to regress in 17% to 34% of cases.

Finally, gallstones have a proven association with gallbladder carcinoma (see Chapter 49 ). In a review of 200 consecutive calculous cholecystitis specimens, Albores-Saavedra and colleagues reported that 83% exhibited epithelial hyperplasia, 13.5% atypical hyperplasia, and 3.5% carcinoma in situ. It is not known whether such data apply today, but chronic cholecystitis changes may equate to hyperplasia and dysplasia if not infrequent. Cholecystectomy alone remains sufficient. In areas endemic for gallbladder cancer, the risk of carcinoma increases with larger gallstones. The relative risk rises from 2.4 for stones 2 to 2.9 cm in diameter to 10 for gallstones larger than 3 cm. Some patients with gallbladder calcification also have a higher incidence of gallbladder cancer. Elective cholecystectomy has been recommended in patients with gallstones greater than 3 cm in diameter, but no proof is available to support that such an approach is warranted from an oncologic standpoint. ^{, ,} Preemptive elective cholecystectomy for asymptomatic gallstones is considered in some parts of the world with unusually high gallbladder cancer rates, including some parts of India, Chile, and Mexico.

Symptomatic gallstones

Approximately 20% to 30% of patients with gallstones will develop symptoms, and once this occurs, cholecystectomy is usually indicated for both symptomatic improvement and to prevent further complications (see Chapter 33 ). The spectrum of severity characterizing symptomatic gallstones ranges from episodic pain to life-threatening infection and shock.