Jae Hyuck Chang

Biliary Stricture after Adult Right-Lobe Living-Donor Liver Transplantation with Duct-to-Duct Anastomosis: Long-Term Outcome and Its Related Factors after Endoscopic Treatment

BACKGROUND/AIMS Biliary stricture is the most common and important complication after right-lobe living-donor liver transplantation (RL-LDLT) with duct-to-duct biliary anastomosis. This study evaluated the efficacy and long-term outcome of endoscopic treatment for biliary stricture after LDLT, with the aim of identifying the factors that influence the outcome. METHODS Three hundred and thirty-nine adults received RL-LDLTs with duct-to-duct biliary anastomosis between January 2000 and May 2008 at Kangnam St. Marys Hospital. Endoscopic retrograde cholangiography (ERC) was performed in 113 patients who had biliary stricture after LDLT. We evaluated the incidence of post-LDLT biliary stricture and the long-term outcome of endoscopic treatment for biliary stricture. The factors related to the outcome were analyzed. RESULTS Biliary strictures developed in 121 (35.7%) patients, 95 (78.5%) of them within 1 year of surgery. The mean number of ERCs performed per patient was 3.2 (range, 1 to 11). The serum biochemical markers decreased significantly after ERC (p<0.001). Stent insertion or stricture dilatation during ERC was successful in 90 (79.6%) patients. After a median follow-up period of 33 months from the first successful treatment with ERC, 48 (42.5%) patients achieved treatment success and 12 (10.6%) patients remained under treatment. The factors related to the outcome of endoscopic treatment were nonanastomotic stricture and stenosis of the hepatic artery (p=0.016). CONCLUSIONS Endoscopic treatment is efficacious and has an acceptable long-term outcome in the management of biliary strictures related to RL-LDLT with duct-to-duct biliary anastomosis. Nonanastomotic stricture and stenosis of the hepatic artery are correlated with a worse outcome of endoscopic treatment.

Clinical Outcome of Self-Expandable Metal Stent Placement in the Management of Malignant Proximal Colon Obstruction

Background/Aims There are limited data regarding the clinical outcomes of self-expandable metal stents in the treatment of proximal colon obstruction. We compared the clinical outcomes of stent placement in patients with malignant proximal to distal colon obstructions. Methods We reviewed medical records from 37 consecutive patients from three institutions (19 men; mean age, 72 years) who underwent endoscopic stent placement at a malignant obstruction of the proximal colon. We also examined the records from 99 patients (50 men; mean age, 65 years) who underwent endoscopic stent placement for a distal colon obstruction. Technical success, clinical improvements, complications and stent patency were compared between treatments. Results The technical success rate tended to be lower in stents inserted to treat proximal colon obstructions than in those used to treat distal colon obstructions (86% vs 97%, p=0.06). Clinical improvement was achieved in 78% of patients (29/37) with proximal colonic stenting and in 91% of patients (90/99) with distal colonic stenting (p=0.08). Complications (24% vs 27%), stent migration (8% vs 8%) and stent reocclusion rates (11% vs 17%) did not differ significantly between groups. Two cases of bowel perforation related to stenting (5%) occurred in patients with proximal colonic stenting. Conclusions The technical success and clinical improvement associated with self-expandable metal stents used to treat proximal colon obstruction tend to be lower than cases of distal colon obstruction. Technical failure is an important cause of poor clinical improvement in patients with proximal colon stenting. Complication rates and stent patency appear to be similar in both groups.

Usefulness of the Rendezvous Technique for Biliary Stricture after Adult Right-Lobe Living-Donor Liver Transplantation with Duct-To-Duct Anastomosis

BACKGROUND/AIMS Replacement of a percutaneous transhepatic biliary drainage (PTBD) catheter with inside stents using endoscopic retrograde cholangiography is difficult in patients with angulated or twisted biliary anastomotic stricture after living donor liver transplantation (LDLT). We evaluated the usefulness and safety of the rendezvous technique for the management of biliary stricture after LDLT. METHODS Twenty patients with PTBD because of biliary stricture after LDLT with duct-to-duct anastomosis underwent the placement of inside stents using the rendezvous technique. RESULTS Inside stents were successfully placed in the 20 patients using the rendezvous technique. The median procedure time was 29.6 (range, 7.5-71.8) minutes. The number of inside stents placed was one in 12 patients and two in eight patients. One mild acute pancreatitis and one acute cholangitis occurred, which improved within a few days. Inside stent related sludge or stone was identified in 12 patients during follow-up. Thirteen patients achieved stent-free status for a median of 281 (range, 70-1,351) days after removal of the inside stents. CONCLUSIONS The rendezvous technique is a useful and safe method for the replacement of PTBD catheter with inside stent in patients with biliary stricture after LDLT with duct-to-duct anastomosis. The rendezvous technique could be recommended to patients with angulated or twisted strictures.

A Novel Placement Method of the Bravo Wireless pH Monitoring Capsule for Measuring Intragastric pH

Purpose The delivery system of the Bravo capsule was designed for placement on the esophagus. We evaluated the feasibility of our novel placement method of the Bravo capsule using a clip to monitor intragastric pH and to compare the accuracy of the Bravo wireless system to the traditionally used Slimline catheter-Mark III Digitrapper pH monitoring system. Methods The Bravo capsule was placed by clip or conventional delivery system using suction on the gastric wall in 20 fasted subjects. A separate group of ten healthy volunteers underwent simultaneous intragastric pH monitoring for comparison of the two systems with meals. Results Early dislodgment rate of the capsules was lower when placed using clipping (20%) than using conventional delivery system (70%) within 48 h after placement. We observed prominent movement of one catheter in the stomach during the study. Post-test calibration drifts of the catheters at pH 7.01 were significantly greater than those of the Bravo capsules (P = 0.02). Conclusion Our novel clipping method of the Bravo pH capsule placement provided accurate monitoring of intragastric pH with merits of tolerability, acid stability, and fixing position.

Role of magnetic resonance cholangiopancreatography for choledocholithiasis: Analysis of patients with negative MRCP

Abstract Objective. To investigate the negative predictive value of magnetic resonance cholangiopancreatography (MRCP) for common bile duct (CBD) stones and the prognosis of patients suspected to have choledocholithiasis in whom the MRCP was negative for CBD stones. Methods. We enrolled the patients suspected to have choledocholithiasis in whom the MRCP was negative for the CBD stones between January 2008 and March 2011 and retrospectively analyzed the outcomes of 115 patients. Results. Endoscopic retrograde cholangiopancreatography (ERCP) was performed in 27 patients (23%, group 1), and none had CBD stones. The negative predictive value of MRCP was 100%. During a median follow-up of 18.3 months, acute cholangitis with newly developed CBD stones occurred in two patients. Eighty-eight patients (77%, group 2) did not undergo ERCP and all recovered from acute cholangitis without CBD surgery. During a median follow-up of 18.7 months, acute cholangitis, acute cholecystitis, gallstone pancreatitis, and pancreatico-biliary cancers occurred in four (4.6%), three (3.5%), one (1.2%), and three (3.5%) patients, respectively. New CBD stones were found in only two patients among four patients with recurrent acute cholangitis. No patient had recurrent cholangitis caused by MRCP-missed CBD stones. The rates of recurrent cholangitis and cholangitis-free survival did not differ between groups 1 and 2. Conclusion. The negative predictive value of MRCP was very high. ERCP can be reserved for patients who are MRCP negative for choledocholithiasis, but close follow-up is needed because of recurrent cholangitis or pancreatico-biliary cancer.

Current diagnosis and treatment of benign biliary strictures after living donor liver transplantation

Despite advances in surgical techniques, benign biliary strictures after living donor liver transplantation (LDLT) remain a significant biliary complication and play an important role in graft and patient survival. Benign biliary strictures after transplantation are classified into anastomotic or non-anastomotic strictures. These two types differ in presentation, outcome, and response to therapy. The leading causes of biliary strictures include impaired blood supply, technical errors during surgery, and biliary anomalies. Because patients usually have non-specific symptoms, a high index of suspicion should be maintained. Magnetic resonance cholangiography has gained widespread acceptance as a reliable noninvasive tool for detecting biliary complications. Endoscopy has played an increasingly prominent role in the diagnosis and treatment of biliary strictures after LDLT. Endoscopic management in LDLT recipients may be more challenging than in deceased donor liver transplantation patients because of the complex nature of the duct-to-duct reconstruction. Repeated aggressive endoscopic treatment with dilation and the placement of multiple plastic stents is considered the first-line treatment for biliary strictures. Percutaneous and surgical treatments are now reserved for patients for whom endoscopic management fails and for those with multiple, inaccessible intrahepatic strictures or Roux-en-Y anastomoses. Recent advances in enteroscopy enable treatment, even in these latter cases. Direct cholangioscopy, another advanced form of endoscopy, allows direct visualization of the inner wall of the biliary tree and is expected to facilitate stenting or stone extraction. Rendezvous techniques can be a good option when the endoscopic approach to the biliary stricture is unfeasible. These developments have resulted in almost all patients being managed by the endoscopic approach.

Size and type of periampullary duodenal diverticula are associated with bile duct diameter and recurrence of bile duct stones

Periampullary diverticula (PAD) are not uncommon findings during endoscopic retrograde cholangiopancreatography, but its clinical significance had not been established. To investigate the clinical characteristics associated with PAD and their relationships with the type and size of PAD in patients with common bile duct (CBD) stones was aimed.

Diagnostic value of the PPI test for detection of GERD in Korean patients and factors associated with PPI responsiveness

Abstract Objectives. Data supporting the use of the proton pump inhibitor (PPI) test as a diagnostic test of gastroesophageal reflux disease (GERD) in Asia are lacking. The aims of this study were to evaluate the diagnostic characteristics of the PPI test and factors associated with responsiveness to PPIs. Methods. The PPI test was evaluated using lansoprazole (30 mg bid) for two weeks. All patients underwent endoscopy after symptom assessment. Patients without erosive esophagitis (ERD) underwent 48 h esophageal Bravo pH monitoring. Subjects were considered to be responsive to PPIs if they reported a > 50% reduction in reflux symptom score. Results. Seventy-three patients (M:F = 40:37, 47 ± 13 years) were enrolled. We identified 46 patients with ERD, 18 patients with nonerosive reflux disease (NERD) and 9 patients without GERD. The PPI response rate was higher in patients with GERD than in patients without GERD (49/64, 77% vs. 4/9, 44%; p < 0.05). The sensitivity, specificity, and positive and negative predictive values were 77%, 56%, 92% and 25%, respectively. The PPI responsiveness was 80% (37/46) in the ERD group and 67% (12/18) in the NERD group. PPI response was not affected by age, sex, Helicobacter pylori, the psychological characteristics or cytochrome P2C genotypes. ERD and symptom-reflux association were the factors affecting PPI responsiveness. Conclusions. The PPI test was modestly sensitive and specific for diagnosing GERD. However, it would be useful for discriminating patients with ERD. In the NERD group, patients with positive symptom-reflux association would be most benefit from PPI treatment.

Effect of Dynamic Position Changes on Adenoma Detection During Colonoscope Withdrawal: A Randomized Controlled Multicenter Trial.

OBJECTIVES:Adequate luminal distension is essential for improving adenoma detection during colonoscope withdrawal. A few crossover studies have reported that dynamic position changes maximize luminal distension and increase adenoma detection rates (ADR). We designed a multicenter, randomized, parallel-group trial to verify the effect of dynamic position changes on colonic adenoma detection.METHODS:This study was conducted at the six hospitals of the Catholic University of Korea. Patients aged 45–80 years who underwent a colonoscopy for the first time were included. In the position change group, the position changes during colonoscope withdrawal were as follows: cecum, ascending colon, and hepatic flexure: left lateral position; transverse colon: supine position; splenic flexure, descending colon, sigmoid colon, and rectum: right lateral position. In the control group, the examinations were performed entirely in the left lateral position during colonoscope withdrawal. The primary outcome measure was the ADR, which was defined as the proportion of patients with ≥1 adenoma.RESULTS:A total of 1,072 patients were randomized into the position change group (536 patients) or the control group (536 patients). The ADR was higher in the position change group than in the control group (42.4 vs. 33.0%, P=0.002). More adenomas were detected per subject in the position change group (0.90 vs. 0.67, P=0.01). Increases in the number of adenomas were observed in examinations of the transverse colon (0.22 vs. 0.13, P=0.016) and the left colon (0.37 vs. 0.27, P=0.045). A significant increase in the ADR was observed for endoscopists with a relatively low detection rate. For endoscopists with a high detection rate, non-significant changes in the ADR were observed.CONCLUSIONS:Dynamic position changes during colonoscope withdrawal increased the ADR.

Gastroprotective Effects of Grape Seed Proanthocyanidin Extracts against Nonsteroid Anti-Inflammatory Drug-Induced Gastric Injury in Rats

Background/Aims To investigate the gastroprotective effects of grape seed proanthocyanidin extracts (GSPEs) against nonsteroid anti-inflammatory drug (NSAID)-induced gastric mucosal injury in rats. Methods Sprague-Dawley rats were randomly allocated to the normal control, indomethacin, low-dose GSPE, high-dose GSPE and misoprostol groups. All groups except the normal control group received pretreatment drugs for 6 consecutive days. On the 5th and 6th day, indomethacin was administered orally to all groups except for normal control group. The microscopic features of injury were analyzed. The levels of gastric mucosal glutathione, gastric mucosal prostaglandin E2 (PGE2), and proinflammatory cytokines were investigated. Results The total areas of ulceration in the GSPE and misoprostol groups were significantly decreased compared with the indomethacin group (p<0.05). However, a difference in ulcer formation among the drug treatment groups was not observed. Meanwhile, the glutathione levels in the high-dose GSPE group were higher than those of both the indomethacin and misoprostol groups (p<0.05) and were similar to those of the normal control group. Additionally, there was no difference among the groups in the levels of gastric mucosal PGE2 and proinflammatory cytokines. Conclusions High-dose GSPE has a strong protective effect against NSAID-induced gastric mucosal injury, which may be associated with the antioxidant effects of GSPE.