Background/Aims: Ursodeoxycholic acid (UDCA) is the only well-established and widely used agent for dissolving gallstones. Epidemiological and animal studies have suggested potential therapeutic benefits of n-3 polyunsaturated fatty acids (PUFA) for dissolving cholesterol gallstones. We evaluated whether adding PUFA to UDCA improves gallstone dissolution in patients with cholesterol gallstones. Methods: This randomized, prospective, preliminary clinical trial compared the efficacy and safety of UDCA plus PUFA combination therapy (combination group) with those of UDCA monotherapy (monotherapy group). The inclusion criteria were a gallstone diameter ≤15 mm on ultra-sonography, radiolucent stones on plain X-ray, and no to mild symptoms. Gallstone dissolution rates, response rates, and adverse events were evaluated. Results: Of the 59 screened patients, 45 patients completed treatment (24 and 21 in the monotherapy and combination groups, respectively). The gallstone dissolution rate tended to be higher in the combination group than in the monotherapy group (45.7% vs 9.9%, p=0.070). The radiological response rate was also significantly higher in the combination group (90.5% vs 41.7%, p=0.007). In both groups, dissolution and response rates were higher in patients with gallbladder sludge than in those with distinct stones. Four adverse events (two in each group) were observed, none of which were study drug-related or led to drug discontinuation. The incidence of these adverse events was similar in both groups (combination vs monotherapy: 9.5% vs 8.3%, p=0.890). Conclusions UDCA plus PUFA therapy dissolves cholesterol gallstones more effectively than UDCA monotherapy, without significant complications. Further prospective, large-scale studies of this combination therapy are warranted.

Background/Aims: Ursodeoxycholic acid (UDCA) is the only well-established and widely used agent for dissolving gallstones. Epidemiological and animal studies have suggested potential therapeutic benefits of n-3 polyunsaturated fatty acids (PUFA) for dissolving cholesterol gallstones. We evaluated whether adding PUFA to UDCA improves gallstone dissolution in patients with cholesterol gallstones. Methods: This randomized, prospective, preliminary clinical trial compared the efficacy and safety of UDCA plus PUFA combination therapy (combination group) with those of UDCA monotherapy (monotherapy group). The inclusion criteria were a gallstone diameter ≤15 mm on ultra-sonography, radiolucent stones on plain X-ray, and no to mild symptoms. Gallstone dissolution rates, response rates, and adverse events were evaluated. Results: Of the 59 screened patients, 45 patients completed treatment (24 and 21 in the monotherapy and combination groups, respectively). The gallstone dissolution rate tended to be higher in the combination group than in the monotherapy group (45.7% vs 9.9%, p=0.070). The radiological response rate was also significantly higher in the combination group (90.5% vs 41.7%, p=0.007). In both groups, dissolution and response rates were higher in patients with gallbladder sludge than in those with distinct stones. Four adverse events (two in each group) were observed, none of which were study drug-related or led to drug discontinuation. The incidence of these adverse events was similar in both groups (combination vs monotherapy: 9.5% vs 8.3%, p=0.890). Conclusions UDCA plus PUFA therapy dissolves cholesterol gallstones more effectively than UDCA monotherapy, without significant complications. Further prospective, large-scale studies of this combination therapy are warranted.

Background/Aims: Ursodeoxycholic acid (UDCA) is the only well-established and widely used agent for dissolving gallstones. Epidemiological and animal studies have suggested potential therapeutic benefits of n-3 polyunsaturated fatty acids (PUFA) for dissolving cholesterol gallstones. We evaluated whether adding PUFA to UDCA improves gallstone dissolution in patients with cholesterol gallstones. Methods: This randomized, prospective, preliminary clinical trial compared the efficacy and safety of UDCA plus PUFA combination therapy (combination group) with those of UDCA monotherapy (monotherapy group). The inclusion criteria were a gallstone diameter ≤15 mm on ultra-sonography, radiolucent stones on plain X-ray, and no to mild symptoms. Gallstone dissolution rates, response rates, and adverse events were evaluated. Results: Of the 59 screened patients, 45 patients completed treatment (24 and 21 in the monotherapy and combination groups, respectively). The gallstone dissolution rate tended to be higher in the combination group than in the monotherapy group (45.7% vs 9.9%, p=0.070). The radiological response rate was also significantly higher in the combination group (90.5% vs 41.7%, p=0.007). In both groups, dissolution and response rates were higher in patients with gallbladder sludge than in those with distinct stones. Four adverse events (two in each group) were observed, none of which were study drug-related or led to drug discontinuation. The incidence of these adverse events was similar in both groups (combination vs monotherapy: 9.5% vs 8.3%, p=0.890). Conclusions UDCA plus PUFA therapy dissolves cholesterol gallstones more effectively than UDCA monotherapy, without significant complications. Further prospective, large-scale studies of this combination therapy are warranted.

Background/Aims: Ursodeoxycholic acid (UDCA) is the only well-established and widely used agent for dissolving gallstones. Epidemiological and animal studies have suggested potential therapeutic benefits of n-3 polyunsaturated fatty acids (PUFA) for dissolving cholesterol gallstones. We evaluated whether adding PUFA to UDCA improves gallstone dissolution in patients with cholesterol gallstones. Methods: This randomized, prospective, preliminary clinical trial compared the efficacy and safety of UDCA plus PUFA combination therapy (combination group) with those of UDCA monotherapy (monotherapy group). The inclusion criteria were a gallstone diameter ≤15 mm on ultra-sonography, radiolucent stones on plain X-ray, and no to mild symptoms. Gallstone dissolution rates, response rates, and adverse events were evaluated. Results: Of the 59 screened patients, 45 patients completed treatment (24 and 21 in the monotherapy and combination groups, respectively). The gallstone dissolution rate tended to be higher in the combination group than in the monotherapy group (45.7% vs 9.9%, p=0.070). The radiological response rate was also significantly higher in the combination group (90.5% vs 41.7%, p=0.007). In both groups, dissolution and response rates were higher in patients with gallbladder sludge than in those with distinct stones. Four adverse events (two in each group) were observed, none of which were study drug-related or led to drug discontinuation. The incidence of these adverse events was similar in both groups (combination vs monotherapy: 9.5% vs 8.3%, p=0.890). Conclusions UDCA plus PUFA therapy dissolves cholesterol gallstones more effectively than UDCA monotherapy, without significant complications. Further prospective, large-scale studies of this combination therapy are warranted.

Background/Aims: Endoscopic ultrasound-guided fine-needle aspiration/biopsy (EUS-FNA/B) is essential in diagnosing solid pancreatic lesions (SPLs), but without rapid on-site evaluation (ROSE), a repeat EUS-FNA/B is crucial for clarifying an inconclusive diagnosis. We aimed to evaluate factors associated with improved diagnostic performance of repeat EUS-FNA/B for initially inconclusive SPL diagnoses without ROSE. Methods: Of 5,894 patients subjected to EUS-FNA/B, 237 (4.0%) with an initially inconclusive diagnosis of SPLs were retrospectively enrolled from five tertiary medical centers between January 2016 and June 2021. Diagnostic performance and procedural factors of EUS-FNA/B were analyzed. Results: The diagnostic accuracies of first and repeat EUS-FNA/B were 96.2% and 67.6%, respectively. Of 237 patients with an inconclusive diagnosis from initial EUS-FNA/B, 150were pathologically diagnosed after repeat EUS-FNA/B. In multivariate analysis of repeat EUS-FNA/B, tumor location (body/tail vs head: odds ratio [OR], 3.74; 95% confidence inter-val [CI], 1.48 to 9.46), number of needle passes (≥4 vs ≤3: OR, 4.80; 95% CI, 1.44 to 15.99),needle type (FNB vs FNA: OR, 3.26; 95% CI, 1.44 to 7.36), needle size (22 gauge vs 19/20 gauge: OR, 2.35; 95% CI, 1.19 to 4.62), and suction method (suction vs others: OR, 5.19;95% CI, 1.30 to 20.75) were associated with a significantly improved diagnostic performance. Conclusions Repeat EUS-FNA/B is essential for patients with an inconclusive EUS-FNA/B without ROSE. To improve the diagnostic performance of repeated EUS-FNA/B, it is recom-mended that 22-gauge FNB needles, ≥4 needle passes, and suction methods are used.

Background/Aims: Acute pancreatitis (AP) is a common gastrointestinal disease associated with hospitalization. With the increase in its incidence, AP has become a greater burden on healthcare resources. Early identification of patients with mild AP can facilitate the appropriate use of resources. We aimed to investigate the ability of inflammatory markers, including interleukin-6 (IL-6), procalcitonin, and C-reactive protein (CRP), as well as various scoring systems to differentiate mild AP from more severe diseases. Methods: We retrospectively investigated patients hospitalized with AP, for whom severity assessment and clinical course confirmation were possible. Inflammatory markers were measured at admission, and CRP levels were measured 24 hours after admission (CRP2). Predictive values were calculated using the area under the receiver operating characteristic curve (AUROC) and logistic regression model analysis. Results: Of 103 patients with AP, 42 (40.8%) were diagnosed with mild AP according to the revised Atlanta classification. Based on the AUROC, IL-6 (0.755, p<0.001), CRP2 (0.787, p<0.001), and computed tomography severity index (CTSI) (0.851, p<0.001) were useful predictors of mild AP. With standard cutoff values, the diagnostic sensitivity, specificity, and accuracy were 83.3%, 62.3%, and 70.9% for IL-6 (<50 pg/mL), and 78.6%, 63.9%, and 69.9% for CRP2 (<50 mg/L), respectively. The AUROC of IL-6 and CRP2 were significantly higher than those of other inflammatory markers and were not significantly different from that of CTSI. Conclusions IL-6, CRP2, and CTSI are helpful for early differentiation of AP severity. Among inflammatory markers, IL-6 has the advantage of early prediction of mild pancreatitis at the time of admission.

Background/Aims: The use of a self-expandable metal stent (SEMS) is recommended for unresectable malignant biliary obstruction (MBO). Stent-related adverse events might differ according to the position of the stent through the ampulla of Vater (AOV). We retrospectively evaluated SEMS patency and adverse events according to the position of the SEMS. Methods: In total, 280 patients who underwent endoscopic SEMS placement due to malignant distal biliary obstruction were analyzed retrospectively. Suprapapillary and transpapillary SEMS insertions were performed on 51 patients and 229 patients, respectively. Results: Between the suprapapillary group (SPG) and transpapillary group (TPG), the stent patency period was not significantly different (median [95% confidence interval]: 107 days [82.3 to 131.7] vs 120 days [99.3 to 140.7], p=0.559). There was also no significant difference in the rate of adverse events. In subgroup analysis, the stent patency for an MBO located within 2 cm from the AOV was found to be significantly shorter than that for an MBO located more than 2 cm from the AOV in the SPG (64 days [0 to 160.4] vs 127 days [82.0 to 171.9], p<0.001) and TPG (87 days [52.5 to 121.5] vs 130 [97.0 to 162.9], p<0.001). Patients with an MBO located within 2 cm from the AOV in both groups had a higher percentage of duodenal invasion (SPG: 40.0% vs 4.9%, p=0.002; TPG: 28.6% vs 2.9%, p<0.001) than patients with an MBO located more than 2 cm from the AOV. Conclusions The SPG and TPG showed similar results in terms of stent patency and rate of adverse events. However, patients with an MBO located within 2 cm from the AOV had a higher percentage of duodenal invasion with shorter stent patency than those with an MBO located more than 2 cm from the AOV, regardless of stent position.

Background/Aims: Sphincterotomes are essential for endoscopic sphincterotomy (EST) and can also be used for cannulation in ERCP.A domestic new pull-type sphincterotome (Optimos™, Taewoong, Goyang, Korea) provides acceptable technical feasibility and safety, but there are no comparison results. Thus, this study compared the clinical performance and safety of Optimos™ sphincterotome to a conventional sphincterotome (CleverCut3™, Olympus, Tokyo, Japan) in patients who underwent ERCP. Methods: From April 2021 to July 2021, a randomized prospective comparative study was conducted on 104 consecutive patients who underwent ERCP in three medical centers. The primary endpoint was the clinical performance and safety of sphincterotomes during ERCP. Results: One hundred and four patients were assigned randomly to the Optimos™ group (n=51) or CleverCut3™ group (n=53). All demographic characteristics did not differ between the groups except the BMI. The technical success rate for cannulation, performance of EST, and total procedure time were similar in the two groups. The adverse events did not differ, even though two cases of post-ERCP pancreatitis occurred in CleverCut3™. On the other hand, in questionnaire analysis, CleverCut™ showed a better user’s convenience (median [interquartile range] 4.0 [3.0-4.0] vs. 3.0 [3.0-4.0], p=0.013) and manipulability (median [interquartile range], 4.0 [3.0-4.0] vs. 3.0 [3.0-4.0], p=0.039) than Optimos™, even though the other profiles did not reveal any differences. Conclusions New domestic pull-type sphincterotome can offer comparable clinical performance and safety profiles to conventional sphincterotome, but it needs refinements to increase the user’s convenience and manipulability. Further improvement and innovation will be required to advance domestic medical devices.

Objective: Biliary decompression through bile drainage is a key treatment for common bile duct obstruction with cholangitis. However, the effectiveness of early interventions has not been studied sufficiently in Korea. This study investigated the effectiveness of fast-track biliary decompression. Methods: A group of patients diagnosed with common bile duct obstruction with cholangitis between January 1, 2014, and December 31, 2019, was reviewed retrospectively. We divided them into two groups: before and after the implementation of fast-track biliary decompression. The following items were analyzed in the two groups: time to intervention, number of hospital days, length of stay in the emergency department, and intensive care unit (ICU) admission. Results: Between January 1, 2014, and December 31, 2019, 418 patients were admitted for common bile duct obstruction, and a total of 369 patients were included in this study. Of these, 168 patients visited the hospital prior to implementation of the treatment, and 201 patients visited after implementation. The time to intervention was 6.1 (4.2-11.0) hours in the fast-track group, which was about 9 hours shorter than the other group (P<0.001). There was no statistical difference in the number of hospital days, emergency department length of stay, and ICU admissions (P=0.535, P=0.034, P=0.322). Conclusion The time to intervention was shortened significantly in the fast-track group. However, we did not observe a significant improvement in patient prognosis. It may be possible that the procedure time may need to be shortened for a better prognosis. This should be investigated in future studies.