Management and Outcome of Borderline Common Bile Duct with Stones: A Prospective Randomized Study

Abstract

Introduction:

Management of common bile duct stones (CBDS) in patients with borderline CBD presents a surgical challenge. The aim of this study was to compare conservative treatment with endoscopic stone extraction for the treatment of borderline CBD with stones.

Patients and Methods:

This prospective randomized controlled trial includes patients with CBDS in borderline CBD (CBD <10 mm) associated with gallbladder stones who were treated with conservative treatment or endoscopic stone extraction followed by laparoscopic cholecystectomy (LC) and intraoperative cholangiogram (IOC). The primary outcome was successful CBD clearance. The secondary outcomes were the overall complications, cost, and hospital stay.

Results:

LC and IOC revealed complete clearance of CBDS in 48 (96%) cases in the endoscopic retrograde cholangiopancreatography (ERCP) group (52% of patients by ERCP, and 44% of patient passed the stone spontaneously), and in the remaining two patients, the CBDS was removed by transcystic exploration. In the conservative group, LC and IOC revealed complete clearance of CBDS in 90% of cases, and in the remaining 10% of patients, the CBDS was removed by transcystic exploration. Post-ERCP pancreatitis (PEP) is noticed significantly in the ERCP group (2 [4%] versus 8 [16%]; P = .04). The average net cost was significantly higher in the ERCP group. Recurrent biliary symptoms developed significantly in the ERCP group after 1 year (10% versus 0%; P = .02) in the form of recurrent cholangititis and recurrent CBDS.

Conclusions:

Management of CBDS in patients with borderline CBD represents a surgical challenge. Borderline CBD increases the technical difficulty of ERCP and increases the risk of PEP. Conservative management of CBDS in borderline CBD not only avoids the risks inherent in ERCP and unnecessary preoperative ERCP, but it is also effective in clearing CBDS. The hepatobiliary surgeon should consider a conservative line of treatment in CBDS in borderline CBD in order to decrease the cost and avoid unnecessary ERCP.

Introduction

Common bile duct stones (CBDS) are seen in approximately 7%–12% of patients who undergo cholecystectomy.^1,2 CBDS can cause serious complications such as cholangitis, pancreatitis, or liver abscess. Endoscopic retrograde cholangiopancreatography (ERCP) with endoscopic sphincterotomy (ES) is a well-established therapeutic procedure for the management of CBDS. It is estimated that nearly 85%–95% of all CBDS can be managed effectively by ERCP.^3–6 It is well established that small stones may pass through the ampulla of Vater spontaneously.^7,8 Moreover, it is not clear what stone size precludes transpapillary migration into the duodenum or which criteria will predict complications of pancreatitis or cholangitis if CBDS are not treated. Therefore, it is generally recommended to treat CBDS whenever detected.⁸ Many studies have found that preoperative ERCP is a useless procedure in 40%–60% of cases due to stones being passed, failed clearance of CBD, and retained stones, despite its complications.^3–8

Management of CBDS in cases of borderline CBD (CBD <10 mm diameter) represents a surgical challenge.⁹ Borderline CBD increases the technical difficulty of ERCP and has been found to increase the risk of post-ERCP pancreatitis (PEP).^10–12 PEP remains the most devastating and frequent complication following ERCP, affecting around 5%–7% of cases, which can increase to 20%–40% in high-risk patients.^13–16 The optimum approach for management of borderline CBD whether by conservative treatment (spontaneous passage of the stone through the papilla) or by endoscopic stone extraction has been reported less in the literature.

The aim of this study was to evaluate the best line of treatment for borderline CBD associated with gallbladder stones, whether by conservative treatment or endoscopic stone extraction as regards the complete clearance rate of the CBDS followed by laparoscopic cholecystectomy (LC). The study also evaluated the overall complications related to each approach, technical difficulties, conversion rate during LC, and cost–benefit relationship of each line of treatment.

Materials and Methods

Study design

This prospective randomized controlled trial included patients with CBDS in borderline CBD (CBD <10 mm in diameter) associated with gallbladder stones who were treated by conservative treatment or endoscopic stone extraction followed by LC from April 2012 to March 2014 at the Gastroenterology Surgical Center, Mansoura University, Egypt. Inclusion criteria included patients with a CBD diameter of <10 mm with one or two stones. The size of the stones was ≤5 mm. Serum bilirubin level was <10 mg/dL. A serum glutamic pyruvic transaminase (SGPT)/serum glutamic-oxaloacetic transaminase (SGOT) ratio <300 IU/L is associated with gallbladder stones. Exclusion criteria included previous cholecystectomy; a history of acute cholecystitis, pancreatitis, or cholangitis; a history of endoscopic sphincterotomy; patients unfit for cholecystectomy; no gallbladder stones; and patients with altered gastrointestinal anatomy.

Informed consent was obtained from all patients included in the study, after a careful explanation of the nature of the disease, and possible treatment with its complications. The study was approved by the Institutional Review Board.

Study procedure

All patients were subjected to careful history taking, clinical examination, and laboratory investigation, including total serum bilirubin, SGPT, and SGOT. Abdominal ultrasound was done for all cases to assess gallbladder and CBD diameter and stones. Magnetic resonance cholangiography (MRCP) was done in all cases to confirm the diameter and presence of CBDS. Participating surgeons were experienced laparoscopic biliary and ERCP surgeons (each had performed >500 cases of ERCP and >1500 biliary operations).

Randomization

Patients were randomized to either conservative treatment or ERCP and stone extraction. The randomization process was done using the closed envelop method, and was drawn by a nurse in the outpatient clinic.

Conservative treatment group

Patients received medical treatment in the form of antibiotics (third-generation cephalosporin), analgesics, and antispasmodics for 3 days. These patients were followed up for improvement of clinical symptoms and serum bilirubin level, and an abdominal ultrasound (US) was carried out to assess the CBDS.

An improvement was declared if the stone passed spontaneously to the duodenum and CBD was completely clear of stones, as indicated by US, and serum bilirubin decreased within 3 days of LC and intraoperative cholangiogram (IOC).

There was deemed to be no improvement (failed conservative treatment) if the stone did not pass spontaneously to the duodenum, as indicated by US, serum bilirubin increased, and the patient underwent early LC and IOC. If residual stone was present, it was managed by trial transcystic exploration.

Preoperative ERCP group

Patients in the ERCP group underwent preoperative ERCP and wide papillotomy and stone extraction directly followed by LC and IOC within 3 days. If residual stone was present, it was managed by trial transcystic exploration.

Data collection

Preoperative data were collected, including patient age, sex, clinical symptoms (jaundice, pain, fever, and vomiting), associated comorbidities (diabetes mellitus, hypertension), as well as preoperative workup data, including laboratory investigations. The size of the CBD and stone detected were based on MRCP findings done for all patients. Patients were monitored for complications following each line of treatment such as PEP, bleeding, and perforation.

IOC was done for all patients to ensure complete clearance of CBD. Degree of adhesion, diameter of cystic duct, and methods of cystic duct closure whether by clips or ligatures were detected. Management of residual stone detected in cholangiogram was evaluated. Rate, cause, and outcome of conversion to open cholecystectomy were assessed.

Postoperative data were collected for follow-up laboratory investigations, including white blood cell count, serum bilirubin, and amylase levels on the first and third day postoperatively. Incidence of hospital readmission and further management of missed or recurrent CBDS was evaluated.

Follow-up was carried out at 1 week, 3 months, 6 months, and 1 year postoperatively. All patients underwent a clinical follow-up, laboratory tests, and US to detect recurrent biliary symptoms, including recurrent CBDS, cholangitis, and biliary pancreatitis.

Assessment

The primary outcome was successful CBD clearance. The procedure was classed as failed when the stone was not removed by either the procedure or other methods. The secondary outcomes were the overall complications related to each approach, technical difficulties, conversion rate during LC, cost–benefit relationship of each line of treatment, hospital stay, and recurrent biliary symptoms.

Pancreatitis was defined as new or worsened abdominal pain, together with a high serum amylase level at least three times the normal level.¹⁷ Pancreatitis was graded according to the days of hospital stay and the requirement of intervention. Mild pancreatitis needed hospitalization for 2–3 days, moderate pancreatitis for 4–10 days, and severe pancreatitis for >10 days, with intervention required or complicated by a pseudocyst.¹⁷

The sample size for each group was calculated to set the level of power for the study at 80% with a 5% significance level supposing CBD clearance rates of 40%–60% after preoperative ERCP and 75% after conservative management. Based on these parameters, a sample size of 50 patients in each group was deemed to be sufficient.

Data analysis

All statistical analyses were performed using IBM SPSS Statistics for Windows v20 (IBM Corp, Armonk, NY). A P value of <.05 was considered statistically significant. Shapiro–Wilk's test was used to assess the normality of the data. Descriptive data were expressed as medians with ranges for continuous data. Categorical variables were described using frequency distributions. Comparison of variables was done by independent Student's t-test for continuous variables and chi-square test for categorical variables.

Results

Patients' characteristics

The study flow chart is shown in Figure 1. Of 605 consecutive patients seen during the study period with CBDS, 196 had CBDS in CBD <10 mm in diameter, and 100 patients were included in the study. The mean age of participants was 32.38 ± 7.78 years (range 18–48 years). These patients were randomly divided into two groups: the conservative treatment group or the ERCP and stone extraction group. Demographic data were comparable in both groups with regard to age, sex, CBD diameter, serum bilirubin, serum amylase, and comorbidity. The characteristics of the two randomized groups are presented in Table 1.

FIG. 1.

Flow diagram of the progress through the phases of a randomized trial (i.e., enrollment, intervention allocation, follow-up, and data analysis).

Table 1.

Demographic Data

	Conservative group	ERCP group	P value
Median age (years)	42 (23–73)	45 (16–63)	.73
Sex:
Male	18 (36%)	19 (38%)	.83
Female	32 (64%)	31 (62%)
Clinical presentation:
Jaundice	40 (80%)	35 (70%)	.25
Pain	44 (88%)	45 (62%)	.75
Diabetes	6 (12%)	7 (14%)	.76
Median serum bilirubin (mg/dL)	1.5 (0.4–9.6)	3.3 (0.4–10)	.09
Serum amylase (IU/L)	59 (28–355)	64 (22–423)	.84
White blood cell count (k/mL)	8.3 (3.1–17.3)	7.7 (2.6–17.4)	.14
Median CBD diameter (mm)	8.5 (5–10)	8 (5–10)	.98
Number of CBDS:
1	40 (80%)	44 (88%)	.27
2	10 (20%)	6 (12%)
CBDS size	4 (2–10)	4 (2–10)	.14

ERCP, endoscopic retrograde cholangiopancreatography; CBD, common bile duct; CBDS, common bile duct stones.

CBD clearance

ERCP was performed in 50 cases, and successful cannulation was done in 45 cases (90%). Precut papallotomy was needed in eight cases to achieve biliary cannulation. Failure of cannulation occurred in five (10%) cases (three due to small papilla, and two due to juxta-diverticulum papilla). ERCP revealed CBDS in 26 (52%) patients and was extracted completely by balloon, and 19 (38%) patients passed the stone spontaneously. In the conservative group, complete clearance of CBD occurred in 38 (76%) cases, while 12 (24%) cases failed to pass the stone spontaneously (Tables 2 and 3).

Table 2.

ERCP Group

Success rate for cannulation	45 (90%)
Number of patients with CBDS	26 (52%)
Number of patients passing stones	19 (38%)
Failed cannulation	5 (10%)
Useless procedure (passed stone + failure of cannulation)	24 (48%)
Number of cannulation attempts:
<5	30 (60%)
≥5	20 (40%)
Median number of pancreatic cannulation:
<3	40 (80%)
≥3	10 (20%)
Precut papillotomy needed for cannulation	8 (16%)

Table 3.

Post Outcome in Both Groups

	Conservative group	ERCP group	P value
Success rate of CBD clearance	38 (76%)	26 (52%)	.01
Useless procedure	12 (24%)	24 (28%)	.01
Serum amylase	59 (35–116)	86 (25–1500)	.001
Number of patients developing pancreatitis	2 (4%)	8 (16%)	.04
Median serum bilirubin (mg%)	1 (0.5–2)	1 (0.5–7)	.03
Median white blood cell count	7.4 (6–15)	7.9 (3–15.9)	.43
IOC:
Clear CBD	45 (90%)	48 (96%)	.24
Residual	5 (10%)	2 (4%)
Number of patients undergoing early LC	48 (96%)	42 (84%)	.05
Number of patients undergoing delayed LC	2 (4%)	8 (16%)	.05
Conversion rate	2 (4%)	1 (2%)	.55
Adhesion	18 (36%)	31 (62%)	.009
Presence of pus in gallbladder	5 (10%)	9 (18%)	.25
Hospital stay (days)	5 (2–8)	4 (2–12)	.77
Recurrent biliary symptoms after 1 year	0	5 (10%)	.02
Recurrent CBDS	0	2 (4%)	.15
Recurrent cholangitis	0	4 (8%)	.04
Recurrent pancreatitis	0	1 (2%)	.31
Cost (US$)	798.9 (712.6–1379.3)	1264.4 (1206.9–1609.2)	.0001

LC, laparoscopic cholecystectomy.

LC and IOC revealed complete clearance of CBD in 48 (96%) cases in the ERCP group (in 26 [52%] patients by ERCP, and in 22 (44%) patients the stone passed spontaneously), and in the remaining two patients, the CBDS was removed by transcystic exploration. In the conservative group, LC and IOC revealed complete clearance of CBDS stone in 45 (90%) cases, and in the remaining 5 (10%) patients, the CBDS was removed by transcystic exploration (Table 3).

The procedure failed significantly more in the ERCP group (12 [24%] versus 24 [48%]; P = .01).

Post-treatment outcome

PEP was noted significantly more in the ERCP group (2 [4%] versus 8 [16%]; P = .04). All cases where pancreatitis developed were managed conservatively (IV fluid, Sandostatin IV, follow-up US). Postoperative amylase was significantly elevated after ERCP (Table 3).

Early LC and IOC was performed in 48 (96%) cases after conservative treatment, while in the remaining two cases, delayed LC and IOC after 2 months was done (due to development of pancreatitis and elevated liver enzymes). Early LC and IOC was done in 42 (84%) patients in the ERCP group, while in the remaining eight cases, delayed LC and IOC after 2 months was done (due to development of pancreatitis and elevated liver enzymes; Table 3).

The median hospital stay was longer in conservative group, but the difference was not significant.

Recurrent biliary symptoms significantly developed in the ERCP group after 1 year of follow-up in five (10%) cases, and no patients developed recurrent symptoms in the conservative group. Recurrent cholangitis is a common presentation in the form of fever, right hypochondrial pain, and mild jaundice, which is treated by antibiotics (third-generation cephalosporin). Recurrent CBDS occurred in two patients in the ERCP group and was managed by ERCP.

Cost

The average net cost (including hospital stay, medical treatment, ERCP, treatment of complications, and LC) was significantly higher in the ERCP group (US$798.9 [range US%712.6–US$1379.3] in conservative group versus US$1264.4 [range US$1206.9–US$1609.2] in ERCP group; P = .0001; Table 3).

Discussion

There are many options available for the extraction of CBDS, including preoperative ERCP before LC, intraoperative ERCP during LC, laparoscopic CBD exploration, open CBD exploration, and postoperative ERCP.^17–20 Many studies have reported that 40%–60% of preoperative ERCP is useless due to the stone passing spontaneously, failed CBDS removal, and residual stones.^7–13 LC with intraoperative ERCP is an alternative option for treatment of gallstones and CBDS.^14,15,21 CBDS passed spontaneously from the papilla in 10%–90% of cases.^7–13 The ideal management of CBDS is dependent on surgical team experience and availability of instruments and endoscopies at the hospital. A single-step procedure obviously has advantages over a two-step procedure.^19,20

Management of CBDS in patients with borderline CBD represents a surgical challenge.^15–17 Borderline CBD increases the technical difficulty of ERCP and has been reported to increase the risk of PEP.^10–15 Despite recent advances in ERCP accessories and techniques, the rate of post-ERCP morbidities has remained unchanged over recent years.^16–18

Many studies have found that 40%–60% of preoperative ERCP is ineffective in complete clearance of CBDS due to stones passing spontaneously, failed cannulation (due to small papilla, juxtadiverticulum papilla, duodenal obstruction), failed CBDS removal, and residual stones.^7–13 Preoperative ERCP is effective treatment for CBDS extraction in most cases, but only 10%–60% of patients will have CBDS on ERCP.^{6–12,21–27} Even with strict selection criteria, >10% of preoperative ERCP are normal, and the possibility of occurrence of post-ERCP pancreatitis varies between 1% and 13.5%.^21–25 Unnecessary pre-ERCP can be avoided in many cases by managing CBDS with conservative treatment, which is effective in most of cases. In this study, ERCP revealed CBDS in 26 (52%) patients and was extracted completely by balloon, and 19 (38%) patients passed the stone spontaneously. In the conservative group, complete clearance of CBD occurred in 38 (76%) cases, while 12 (24%) cases failed to pass the stone spontaneously. This conservative management avoids the risks inherent in ERCP and unnecessary preoperative ERCP.^23–28

PEP is the most frequent complication after ERCP, with the incidence ranging from 5% to 40%.^10–15 PEP is a major cause of morbidities and consumption of hospital resources, and it may lead to patient mortality in severe cases.¹⁵ In a previous study at the authors' center, PEP developed in 51/498 (10.2%) cases of the study population. Forty cases were mild to moderate pancreatitis, and the remaining 11 (21.6%) cases developed severe pancreatitis. Multivariate analysis revealed that young patients aged <35 years old, a CBD diameter >10 mm, and the number of pancreatic cannulations were independent risk factors for the development of PEP.^21–25 In the current study, PEP was noted significantly more in the ERCP group than it was in the conservative group. In all cases, pancreatitis was self-limiting by conservative treatment.

Möller et al.⁷ reported that conservative treatment (natural course) for the management of CBDS was associated with an unfavorable outcome (UO) in 25.3% of cases, which was significantly higher than other methods of clearance of CBD. They concluded that efforts to clear CBD should be performed when small CBDS are present during cholecystectomy because it was associated with more UO. In many studies, CBDS passed spontaneously from the papilla in 10%–90% of cases.^7–13 In the study by Collen et al.,²⁹ an IOC catheter was placed and left trancystic when CBDS were found. The cholangiogram was repeated 2 days and 6 weeks postoperatively and showed a normal finding in more than half of patients, suggesting natural passage of the stones. The transcystic tube in place for 6 weeks with a fine-bore catheter allowed repeated cholangiogram or biliary decompression where necessary in the event of CBDS. In the present study, in the conservative group, complete clearance of CBD occurred in 38 (76%) cases, while 12 (24%) cases failed to pass the stone spontaneously. In the ERCP groups, 19 (38%) patients passed the stone spontaneously (i.e., the ERCP was unnecessary).

Laparoscopic CBD exploration (LCBDE) via choledochotomy and the transcystic duct approach has been widely used with promising results, but it needs surgical experience, instruments, and a choldochoscope. It is also time-consuming, requires a longer learning curve, is difficult in large impacted stone, and has a morbidity rate of about 4%–16%.^26–30 Choledochotomy would be avoided in ducts <10 mm measured at the time of IOC and severely inflamed friable tissues leading to a difficult dissection.³¹ LC and intraoperative ERCP is a single treatment for the management of CBDS that decreases unnecessary ERCP and reduces the need for further surgery following failure of ERCP, thereby decreasing the length of hospital stay and associated costs.^21–25

The average net cost (including hospital stay, medical treatment, ERCP, treatment of complications, and LC) was significantly higher in the ERCP group (US$798.9 [range US$712.6–US$1379.3) in the conservative group versus US$1264.4 [range US41206.9–US$1609.2] in the ERCP group; P = .0001). Conservative treatment for CBDS in CBD >10 mm followed by early LC and IOC decreases unnecessary ERCP and reduces the need for further surgery following failure of ERCP and costs. Increasing efforts to decrease the number of unnecessary ERCPs using MRCP and endoscopic ultrasound are being undertaken.²⁹

In this study, recurrent biliary symptoms developed significantly in the ERCP group after 1 year of follow-up in five (10%) cases, and no patients developed recurrent symptoms in the conservative group. Recurrent cholangitis is a common presentation in the form of fever, right hypochondrial pain, and mild jaundice, which is treated by antibiotics (third-generation cephalosporin). Recurrent CBDS occurred in two patients in the ERCP group and was managed by ERCP.

Conclusions

Management of CBDS in patients with borderline CBD presents a surgical challenge. Borderline CBD increases the technical difficulty of ERCP and increases the risk of PEP. The conservative management of CBDS in borderline CBD not only avoids the risks inherent in ERCP and unnecessary preoperative ERCP, but is also effective in the clearance of the stone. The hepatobiliary surgeon should consider a conservative line of treatment in CBDS in borderline CBD in order to decrease the cost and avoid unnecessary preoperative ERCP.

Footnotes

Disclosure Statement

No competing financial interests exist.

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