Moon Kyung Joo

The prevalence of and risk factors for Barrett's esophagus in a Korean population: A nationwide multicenter prospective study.

Objective The aim of this study was to evaluate the prevalence of Barretts esophagus (BE) in the general Korean population by evaluating screening esophagogastroduodenoscopy. In addition, the risk factors for BE were identified. Method An esophagogastroduodenoscopy examination was performed in 25,536 subjects who had upper endoscopy screening from January 2006 to July 2006. Results Two hundred and fifteen subjects were confirmed to have BE by pathology, thus the prevalence of BE was calculated to be 0.84%. The endoscopic findings were subdivided into 2 groups: BE without reflux esophagitis (RE), which included 167 (77.7%), and BE with RE, which included 48 (22.3%). The analysis of symptoms showed that only 60.1% of the subjects with BE had reflux symptoms. Chest pain [odds ratio (OR): 1.48, 95% confidence interval (CI): 1.04-2.11] and epigastric soreness (OR: 1.42, 95% CI: 1.05-1.93) were found more frequently in the subjects with BE compared with the normal subjects. The multivariate analysis showed that the risk factors for all subjects with BE were a male sex (OR: 1.82, 95% CI: 1.32-2.50), nonsteroidal anti-inflammatory drug use (OR: 2.02, 95% CI: 1.28-3.20), hiatal hernia (OR: 5.66, 95% CI: 3.70-8.66), and an age ≥60 compared with an age <40 (OR: 1.81, 95% CI: 1.07-3.09). There was no significant difference associated with RE. Conclusions The prevalence of BE in Korean patients presenting for a routine health check-up was 0.84%, lower than reported in Western countries. Among the subjects with BE 77.7% did not have endoscopic erosions and there were no reflux symptoms in 39.9%. These results suggest that regular endoscopic screening with a high index of suspicion is necessary for the diagnosis of BE.

Change in Serum Hepatitis B Surface Antigen Level and Its Clinical Significance in Treatment-naïve, Hepatitis B e Antigen-positive Patients Receiving Entecavir

Background/Aim We investigated changes in hepatitis B surface antigen (HBsAg) level and its correlation with clinical outcomes in treatment-naive chronic hepatitis B (CHB) patients undergoing entecavir therapy. Patients and Methods Among 51 hepatitis B e antigen (HBeAg)-positive treatment-naive CHB patients receiving entecavir for more than 1 year, 28 were enrolled. HBsAg levels were measured at baseline, 6 months, and 12 months after treatment using the Architect HBsAg QT assay (Abbott, dynamic; range: 0.05 to 125,000 IU/mL). Serum alanine aminotransferase, HBeAg, anti-HBe, and hepatitis B virus (HBV) DNA (Cobas Taqman: low detection limit 1.84 log10 copies/mL) were measured at baseline and every 3 months. The HBsAg response was defined as an HBsAg level that decreased more than 1 log10 IU/mL from baseline level at 12 months after entecavir treatment. Results Twenty-eight patients were treated for a median period of 21 months (range: 18 to 24 mo). Serum HBsAg level showed a mean of 4.0, 3.7, and 3.6 log10 IU/mL at pretreatment, 6, and 12 months, respectively, and declined significantly (P<0.001). Serum HBV DNA level showed a mean of 8.1, 3.1, and 2.4 log10 copies/mL at pretreatment, 6, and 12 months, respectively, and declined significantly (P<0.001). The decline in HBsAg level was significantly correlated with that of the HBV DNA level at 12 months from baseline (γ=0.391, P=0.044). Five patients showed an HBsAg response, and cumulative incidence of HBeAg loss at 1 year after entecavir treatment was 80% versus 30% in patients with an HBsAg response and those without, respectively (P=0.034). Conclusions Monitoring changes in quantitative HBsAg level could be a useful parameter for assessing the response to entecavir therapy in HBeAg-positive treatment-naive CHB patients.

Prevalence and endoscopic features of eosinophilic esophagitis in patients with esophageal or upper gastrointestinal symptoms

OBJECTIVE:  This study was aimed to evaluate the prevalence of eosinophilic esophagitis (EoE) among patients with esophageal or upper gastrointestinal (UGI) symptoms.

Effects of the Temporary Placement of a Self-Expandable Metallic Stent in Benign Pyloric Stenosis

Background/Aims The use of self-expandable metallic stents (SEMS) is an established palliative treatment for malignant stenosis in the gastrointestinal tract; therefore, its application to benign stenosis is expected to be beneficial because of the more gradual and sustained dilatation in the stenotic portion. We aimed in this prospective observational study to evaluate the efficacy and safety of temporary SEMS placement in benign pyloric stenosis. Methods Twenty-two patients with benign stenosis of the prepylorus, pylorus, and duodenal bulb were enrolled and underwent SEMS placement. We assessed symptom improvement, defined as an increase of at least 1 degree in the gastric-outlet-obstruction scoring system after stent insertion. Results No major complications were observed during the procedures. After stent placement, early symptom improvement was achieved in 18 of 22 patients (81.8%). During the follow-up period (mean 10.2 months), the stents remained in place successfully for 6 to 8 weeks in seven patients (31.8%). Among the 15 patients (62.5%) with stent migration, seven (46.6%) showed continued symptomatic improvement without recurrence of obstructive symptoms. Conclusions Despite the symptomatic improvement, temporary SEMS placement is premature as an effective therapeutic tool for benign pyloric stenosis unless a novel stent is developed to prevent migration.

Hepatitis B Viral Surface Mutations in Patients with Adefovir Resistant Chronic Hepatitis B with A181T/V Polymerase Mutations

The hepatitis B virus (HBV) polymerase gene has overlapping reading frames with surface genes, which allows to alter the amino acid codon of the surface genes. In adefovir (ADV) treated chronic hepatitis B patients carrying rtA181T/rtA181V mutations, overlap with surface gene mutations such as sW172stop/sL173F has been reported. However, the clinical consequences of such surface mutations have not been determined. The aim of this study was to determine the surface gene sequence in ADV-resistant patients carrying the A181T/V mutation and to describe the clinical significance. Of the 22 patients included in this study, 13 were ADV-resistant with rtA181T/V mutations (polymerase mutation group, Group P) and nine were antiviral treatment-naïve (control group, Group C). The Pre-S1 gene mutation, V60A, was detected in 11 patients (Group P=8, Group C=3). A start codon mutation in the Pre-S2 gene was found in five patients (Group P=3, Group C=2). An S gene mutation, sA184V, was found in nine patients, all of whom were in group P. Although sW172stop and sL173F mutations were detected, reduced HBsAg titer was not observed. Further study of these mutations and their clinical implications are needed.

The relationship between hepatitis B virus infection and the incidence of pancreatic cancer: a retrospective case-control study

BACKGROUND/AIMS An association between past history of hepatitis B virus (HBV) infection and pancreatic cancer (PC) has recently been reported. We investigated whether HBV and hepatitis C virus (HCV) infections are associated with the development of PC in Korea. METHODS We retrospectively recruited patients with PC and sex- and, age-matched control patients with stomach cancer (SC) during the previous 5 years. Serum HBsAg and anti-HCV were examined, and data on smoking, alcohol intake, diabetes, and the history of chronic pancreatitis (CP) were collected. RESULTS A total of 506 PC and 1008 SC were enrolled, with respectively 58.1% and 97.3% of these cases being confirmed histologically. The mean age and sex ratio (male:female) were 63.5 years and 1.5:1 in the PC patients and 63.9 years and 1.5:1 in the SC patients respectively (P>0.05). The odds ratios (95% confidence interval, 95% CI) in univariate analysis were 0.90 (0.52-1.56; P=0.70) for HBsAg, 1.87 (0.87-4.01; P=0.11) for anti-HCV, 2.66 (2.04-3.48; P<0.001) for the presence of diabetes, 2.30 (1.83-2.90; P<0.001) for smoking, 1.14 (0.89-1.46; P=0.31) for alcohol intake, and 4.40 (1.66-11.66; P=0.003) for the history of CP. Independent risk factors for PC were presence of diabetes (OR, 2.67; 95% CI, 2.00-3.56; P<0.001), smoking (OR, 2.49; 95% CI, 1.93-3.21; P<0.001) and history of CP (OR, 4.60; 95% CI, 1.56-13.53; P=0.006). CONCLUSIONS There was no significant association between seropositivity for HBsAg or anti-HCV and PC. Further studies are warranted to clarify the association between HBV infection and PC in regions where HBV is endemic.

Endoscopic versus surgical resection of GI stromal tumors in the upper GI tract

BACKGROUND AND AIMS Endoscopic resection has been performed for treatment of GI stromal tumors (GISTs) in the upper GI tract. However, the therapeutic roles of the endoscopic procedure remain debatable. We aimed in this retrospective study to evaluate the feasibility and long-term follow-up results of endoscopic resection of GISTs in the upper GI tract, compared with surgery. METHODS Between March 2005 and August 2014, 130 cases of GIST in the upper GI tract were resected. We compared baseline characteristics and clinical outcomes including R0 resection rate and recurrence rate between the endoscopy group (n = 90) and surgery group (n = 40). RESULTS The most common location of GIST was the stomach body in the endoscopy group, whereas it was the duodenum in the surgery group (P = .001). Tumor size was significantly smaller (2.3 vs 5.1 cm; P < .001), and procedure time (51.8 ± 36.2 vs 124.6 ± 74.7 minutes; P < .001) and hospital stay (3.3 ± 2.4 vs 8.3 ± 5.4 days; P < .001) were significantly shorter in the endoscopy group than in the surgery group. The R0 resection rate was 25.6% in the endoscopy group, whereas it was 85.0% in the surgery group (P = .001), and 50.0% of resected tumors belonged to a very low-risk group in the endoscopy group, whereas 35.0% and 30.0% belonged to low-risk and high-risk in the surgery group (P = .001). However, during 45.5 months of follow-up, the recurrence rate was not significantly different between the 2 groups (2.2% vs 5.0%; P = .586). CONCLUSIONS Endoscopic resection might be an alternative therapeutic modality for GISTs in the upper GI tract in selective cases.

Hepatolithiasis and intrahepatic cholangiocarcinoma: A review

Although the incidence of hepatolithiasis is decreasing as the pattern of gallstone disease changes in Asia, the prevalence of hepatolithiasis is persistently high, especially in Far Eastern countries. Hepatolithiasis is an established risk factor for cholangiocarcinoma (CCA), and chronic proliferative inflammation may be involved in biliary carcinogenesis and in inducing the upregulation of cell-proliferating factors. With the use of advanced imaging modalities, there has been much improvement in the management of hepatolithiasis and the diagnosis of hepatolithiasis-associated CCA (HL-CCA). However, there are many problems in managing the strictures in hepatolithiasis and differentiating them from infiltrating types of CCA. Surgical resection is recommended in cases of single lobe hepatolithiasis with atrophy, uncontrolled stricture, symptom duration of more than 10 years, and long history of biliary-enteric anastomosis. Even after resection, patients should be followed with caution for development of HL-CCA, because HL-CCA is an independent prognostic factor for survival. It is not yet clear whether hepatic resection can reduce the occurrence of subsequent HL-CCA. Furthermore, there are no consistent findings regarding prediction of subsequent HL-CCA in patients with hepatolithiasis. In the management of hepatolithiasis, important factors are the reduction of recurrence of cholangitis and suspicion of unrecognized HL-CCA.

The effect of a proton pump inhibitor on bone metabolism in ovariectomized rats.

Recent studies revealed that long-term intake of proton pump inhibitor (PPI) increases the risk of vertebral or hip fracture; however, the exact mechanism for this is not known. To evaluate the effect of long-term PPI therapy on bone turnover, we analyzed the signaling pathway involved in osteoclast differentiation and bone resorption/formation markers using ovariectomized rats. Six-week-old Sprague-Dawley (S-D) rats were ovariectomized, and two weeks later they were divided into four groups (group A, normal diet + placebo; group B, low calcium diet + placebo; group C, normal diet + PPI; and group D, low calcium diet + PPI). Omeprazole, at a concentration of 30 mg/kg, was administered orally for eight weeks and the rats were sacrificed when they were 16 weeks old. The relative expression levels of the receptor activator of NF-κB ligand (RANKL)/osteoprotegerin (OPG) ratio, c-Fos, nuclear factor of activated T cells c1 (NFATc1) and osteocalcin in femoral bone marrow cells were compared, and serum C-terminal cross-linking telopeptide of type I (CTX-1) levels were determined. The relative ratio of RANKL/OPG was increased in group D, and gene expression levels of c-Fos and NFATc1 were upregulated in groups B and D, which are involved in differentiation and activation of osteoclasts. Furthermore, expression levels of osteocalcin, a bone formation marker, were decreased and levels of serum CTX-1, a bone resorption marker, were increased in group D. Taken together, a low calcium diet and PPI administration are thought to collaborate in order to alter osteoclast activity and bone resorption signaling.

Endoscopic Approach for Major Complications of Bariatric Surgery

As lifestyle and diet patterns have become westernized in East Asia, the prevalence of obesity has rapidly increased. Bariatric surgeries, such as Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), and laparoscopic adjustable gastric banding (LAGB), are considered the first-line treatment option in patients with severe obesity. However, postoperative complications have increased and the proper management of these complications, including the use of endoscopic procedures, has become important. The most serious complications, such as leaks and fistulas, can be treated with endoscopic stent placement and injection of fibrin glue, and a novel full-thickness closure over-the-scope clip (OTSC) has been used for treatment of postoperative leaks. Stricture at the gastrojejunal (GJ) anastomosis site after RYGB or incisura angularis in SG can be managed using stents or endoscopic balloon dilation. Dilation of the GJ anastomosis or gastric pouch may lead to failure of weight loss, and the use of endoscopic sclerotherapy, novel endoscopic suturing devices, and OTSCs have been attempted. Intragastric migration of the gastric band can be successfully treated using various endoscopic tools. Endoscopy plays a pivotal role in the management of post-bariatric complications, and close cooperation between endoscopists and bariatric surgeons may further increase the success rate of endoscopic procedures.