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Featured researches published by Yong Cheol Jeon.


Journal of Gastroenterology | 2003

Changing pattern of antimicrobial resistance of Helicobacter pylori in Korean patients with peptic ulcer diseases

Chang Soo Eun; Dong Soo Han; Joon Yong Park; Yong Cheol Jeon; Joon Soo Hahm; Kyung Suk Kim; Jung Oak Kang

Background. Antibiotic resistance of Helicobacter pylori is problematic because it reduces the efficacy of eradication therapy. It has been suggested that the incidence of resistance is rising. In Korea, information on the antimicrobial resistance of H. pylori is rare. The aim of this study was to assess the prevalence of H. pylori antibiotic resistance at a single center in Korea, and the changes in its antimicrobial resistance, and to detect the mutation foci of clarithromycin-resistant strains. Methods. H. pylori isolates obtained from 224 patients with peptic ulcer disease in Korea between June 1996 and March 2000 were tested for antimicrobial resistance. The minimum inhibitory concentration (MIC) for metronidazole and clarithromycin was determined by the broth microdilution method. Isolates were considered resistant when the MIC was more than 8 μg/ml for metronidazole and more than 1 μg/ml for clarithromycin. To detect H. pylori 23S rRNA mutations, polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was performed. Sequencing was performed on the two strands of the nonrestricted amplicons. Results. Overall, resistance to metronidazole and clarithromycin was detected in 41.9% and 5.4% of patients, respectively. There was no significant difference in metronidazole and clarithromycin resistance according to age group and sex. Six strains were resistant to both metronidazole and clarithromycin. Six of nine clarithromycin-resistant isolates possessed the A2144G mutation in the gene encoding 23S rRNA. Sequencing of the three non-restricted clarithromycin-resistant strains revealed a T-to-C mutation at position 2182. Conclusions. In Korea, there was no significant increase in the prevalence of metronidazole resistance, but clarithromycin-resistant H. pylori strains had increased relatively over the 5-year period. There was an increasing tendency for the emergence of strains with dual resistance to metronidazole and clarithromycin. Many of the clarithromycin-resistant strains possessed the A2144G mutation.


Journal of Clinical Gastroenterology | 2008

Association between GERD-related erosive esophagitis and obesity.

Hang Lak Lee; Chang Soo Eun; Oh Young Lee; Yong Cheol Jeon; Ju Hyun Sohn; Dong Soo Han; Byung Chul Yoon; Ho Soon Choi; Joon Soo Hahm; Min Ho Lee; Dong Hoo Lee

Background and Objectives To date, many studies have reported on the association of obesity with gastroesophageal reflux disease (GERD), although none of these have been systematic. In light of this, we conducted this study to examine the association of obesity and GERD. Subjects and Methods A total of 3363 patients underwent gastroscopy at Hanyang University Health Promotion Center. Among these patients, we prospectively examined patients who were diagnosed with GERD-related erosive esophagitis on endoscopy. Results Multivariate analysis showed that the significant risk factors were waist-to-hip ratio (WHR), hiatal hernia, body mass index (BMI), and smoking. As compared with patients who had a WHR less than 0.8, the multivariate odds ratio for erosive esophagitis were 4.055 for a WHR more than 1.0 and 2.316 for a WHR of 0.8 to 1.0. As compared with patients who had a BMI of 20 to 22.5, the multivariate odds ratio for erosive esophagitis was 3.308 (95% confidence interval, 1.792 to 6.107) for a BMI greater than 30. Conclusions Obesity, especially abdominal obesity, was the significant risk factor for erosive esophagitis.


Journal of Clinical Gastroenterology | 2009

Association between erosive esophagitis and visceral fat accumulation quantified by abdominal CT scan.

Hang Lak Lee; Chang Soo Eun; Oh Young Lee; Yong Cheol Jeon; Dong Soo Han; Byung Chul Yoon; Ho Soon Choi; Joon Soo Hahm; You Hern Ahn; Soon Young Song

Background and Aims There were no objective data presented about the association between erosive esophagitis and abdominal fat. We conducted this study to examine the association of abdominal fat and gastroesophageal reflux disease-related erosive esophagitis. Methods Between May 2004 and October 2005, a total of 100 erosive esophagitis patients diagnosed by upper endoscopy were evaluated in a prospective manner. All study patients and controls underwent abdominal computed tomography (CT) scan. Body fat distribution was assessed by CT with a 10-mm-thick slice at the level of the fourth lumbar vertebra. Results Erosive esophagitis patients presented with a significantly higher mean visceral fat (VF) area (104.68±39.47 vs. 75.90±49.10 cm2, P=0.014) than the control group. However, there was no association between erosive esophagitis and subcutaneous fat area (109.72±49.09 vs. 98.66±52.43 cm2, P=0.379) or total fat area (214.41±78.78 vs. 172.59±90.49 cm2, P=0.054). Multivariate logistic regression analysis demonstrated that high VF areas (P=0.0035), VF/subcutaneous fat area (P=0.005), hiatal hernia (P=0.001), high body mass index (P=0.047), high waist-to-hip ratio (P=0.042), and smoking (P=0.005) are independent risk factors of erosive esophagitis. Conclusions These results suggest a role for visceral obesity, quantified by CT, as a risk factor for erosive esophagitis.


The Korean Journal of Hepatology | 2009

Comparison of various noninvasive serum markers of liver fibrosis in chronic viral liver disease

Sun Min Kim; Joo Hyun Sohn; Tae Yeob Kim; Young Wook Roh; Chang Soo Eun; Yong Cheol Jeon; Dong Soo Han; Young-Ha Oh

BACKGROUND/AIMS The aim of this study was to determine the clinical performances of noninvasive serum markers for the prediction of liver fibrosis in chronic viral liver diseases. METHODS We analyzed a total of 225 patients with chronic viral liver diseases (180 with hepatitis B virus, 43 with hepatitis C virus, and 2 with hepatitis B+C virus) who underwent a liver biopsy procedure at the Hanyang University Guri Hospital between March 2002 and February 2007. Serum was also obtained at the time of liver biopsy. Liver fibrosis was staged according to the scoring system proposed by the Korean Study Group for the Pathology of Digestive Diseases. Various noninvasive serum markers were evaluated, including the aspartate aminotransferase (AST)/alanine aminotransferase (ALT) ratio (AAR), age-platelet (AP) index, AST/platelet ratio index (APRI), cirrhosis discriminant score (CDS), platelet count, hyaluronic acid (HA), and type IV collagen. RESULTS There were 17, 40, 61, 74, and 33 patients at stages F0, F1, F2, F3, and F4, respectively. The overall diagnostic accuracies of each marker, as determined by the area under receiver operating characteristics curves, were APRI=0.822, CDS=0.776, platelet count=0.773, AP index=0.756, HA=0.749, type IV collagen=0.718, and AAR=0.642 for predicting significant fibrosis (> or =F2); and CDS=0.835, platelet count=0.795, AP index=0.794, HA=0.766, AAR=0.711, type IV collagen=0.697, and APRI=0.691 for predicting extensive fibrosis (> or =F3). CONCLUSIONS All noninvasive serum markers evaluated in this study were useful for predicting significant or extensive liver fibrosis in chronic viral liver diseases. In particular, APRI was most useful for the prediction of significant fibrosis, and CDS was most useful for the prediction of extensive fibrosis.


Clinical and molecular hepatology | 2012

A fatal case of hepatitis B virus (HBV) reactivation during long-term, very-low-dose steroid treatment in an inactive HBV carrier

Joong Ho Bae; Joo Hyun Sohn; Hye Soon Lee; Hye Sun Park; Yil Sik Hyun; Tae Yeob Kim; Chang Soo Eun; Yong Cheol Jeon; Dong Soo Han

Hepatitis B virus (HBV) may be reactivated after chemotherapy or immunosuppressive therapy, and therefore administration of antiviral agents before such treatment is recommended. Most reported cases of reactivation are associated with high doses of immunosuppressive agents or combination therapy. We present a case of a previously inactive HBV carrier with an acute severe flare-up during a long-term, very-low-dose (2.5 mg/day) steroid treatment for rheumatoid arthritis. We suggest that even a minimal dose of single-regimen oral steroid can cause reactivation of indolent, inactive HBV.


Clinical and molecular hepatology | 2014

Changes in the seroprevalence of IgG anti-hepatitis A virus between 2001 and 2013: experience at a single center in Korea.

Sung Jun Chung; Tae Yeob Kim; Sun Min Kim; Min Roh; Mi Yeon Yu; Jung Hoon Lee; ChangKyo Oh; Eun Young Lee; Seung Ro Lee; Yong Cheol Jeon; Kyo-Sang Yoo; Joo Hyun Sohn

Background/Aims The incidence of symptomatic hepatitis A reportedly increased among 20- to 40-year-old Korean during the late 2000s. Vaccination against hepatitis A was commenced in the late 1990s and was extended to children aged <10 years. In the present study we analyzed the changes in the seroprevalence of IgG anti-hepatitis A virus (HAV) over the past 13 years. Methods Overall, 4903 subjects who visited our hospital between January 2001 and December 2013 were studied. The seroprevalence of IgG anti-HAV was analyzed according to age and sex. In addition, the seroprevalence of IgG anti-HAV was compared among 12 age groups and among the following time periods: early 2000s (2001-2003), mid-to-late 2000s (2006-2008), and early 2010s (2011-2013). The chi-square test for trend was used for statistical analysis. Results The seroprevalence of IgG anti-HAV did not differ significantly between the sexes. Furthermore, compared to the seroprevalence of IgG anti-HAV in the early 2000s and mid-to-late 2000s, that in the early 2010s was markedly increased among individuals aged 1-14 years and decreased among those aged 25-44 years (P<0.01). We also found that the seroprevalence of IgG anti-HAV in individuals aged 25-44 years in the early 2010s was lower than that in the early 2000s and mid-to-late 2000s. Conclusions The number of symptomatic HAV infection cases in Korea is decreasing, but the seroprevalence of IgG anti-HAV is low in the active population.


Clinical Endoscopy | 2013

Xanthogranulomatous inflammation in terminal ileum presenting as an appendiceal mass: case report and review of the literature.

Jun Sik Yoon; Yong Cheol Jeon; Tae Yeob Kim; Dong Soo Han; Joo Hyun Sohn; Kil Woo Nam; Young Su Nam; Ju Yeon Pyo

Xanthogranulomatous inflammation (XGI) is a rare benign inflammatory disease characterized by aggregation of lipid-laden foamy macrophages. This disease entity has been described in various organs but most commonly in the kidney and gallbladder. The occurrence of this disease in the lower gastrointestinal tract is extremely rare. Its clinical importance is that it can be misdiagnosed as an infiltrative cancer. In this case report, a 52-year-old male complained of right lower quadrant abdominal pain for a period of 3 months. Abdominal computed tomography revealed appendiceal mass and colonoscopy revealed multiple erythematous nodular lesions in the terminal ileum and appendiceal orifice, mimicking appendiceal cancer. Right hemicolectomy was done and the pathological specimen revealed XGI of the terminal ileum. To our knowledge, this is the first case of XGI in terminal ileum presenting as abdominal pain and the appendiceal mass on radiologic findings.


PLOS ONE | 2016

The Optimal Cut-Off Value of Neutrophil-to-Lymphocyte Ratio for Predicting Prognosis in Adult Patients with Henoch-Schönlein Purpura.

Chan Hyuk Park; Dong Soo Han; Jae Yoon Jeong; Chang Soo Eun; Kyo-Sang Yoo; Yong Cheol Jeon; Joo Hyun Sohn

Background The development of gastrointestinal (GI) bleeding and end-stage renal disease (ESRD) can be a concern in the management of Henoch–Schönlein purpura (HSP). We aimed to evaluate whether the neutrophil-to-lymphocyte ratio (NLR) is associated with the prognosis of adult patients with HSP. Methods Clinical data including the NLR of adult patients with HSP were retrospectively analyzed. Patients were classified into three groups as follows: (a) simple recovery, (b) wax & wane without GI bleeding, and (c) development of GI bleeding. The optimal cut-off value was determined using a receiver operating characteristics curve and the Youden index. Results A total of 66 adult patients were enrolled. The NLR was higher in the GI bleeding group than in the simple recovery or wax & wane group (simple recovery vs. wax & wane vs. GI bleeding; median [IQR], 2.32 [1.61–3.11] vs. 3.18 [2.16–3.71] vs. 7.52 [4.91–10.23], P<0.001). For the purpose of predicting simple recovery, the optimal cut-off value of NLR was 3.18, and the sensitivity and specificity were 74.1% and 75.0%, respectively. For predicting development of GI bleeding, the optimal cut-off value was 3.90 and the sensitivity and specificity were 87.5% and 88.6%, respectively. Conclusions The NLR is useful for predicting development of GI bleeding as well as simple recovery without symptom relapse. Two different cut-off values of NLR, 3.18 for predicting an easy recovery without symptom relapse and 3.90 for predicting GI bleeding can be used in adult patients with HSP.


Gut and Liver | 2009

Pseudoinvasion in an Adenomatous Polyp of the Colon Mimicking Invasive Colon Cancer

Tae Jun Byun; Dong Soo Han; Sang Bong Ahn; Hyun Seok Cho; Chang Soo Eun; Yong Cheol Jeon; Joo Hyun Sohn; Young Ha Oh

Pseudoinvasion or pseudocarcinomatous invasion in an adenomatous polyp of the colon can be unfamiliar to an endoscopist. Pseudoinvasion in an adenomatous polyp represents prolapse of the adenomatous epithelium into its stalk. In most cases its morphology does not differ from of general adenomatous polyps, but in some cases it can morphologically mimic a malignant polyp with submucosal invasion due to mass-like lesioning of its stalk. This makes it difficult for endoscopists to differentiate pseudoinvasion in an adenoma from an invasive carcinoma by conventional endoscopy; instead, endoscopic ultrasonography can provide useful information for differentiating these conditions. We report on an 82-year-old man who presented with a large pedunculated polyp with a thick stalk in the sigmoid colon, which mimicked a submucosal invasive carcinoma. The patient was diagnosed with pseudoinvasion in an adenomatous polyp after segmental resection of the sigmoid colon.


Digestive Diseases and Sciences | 2005

Pedunculated Angiodysplasia of the Colon Treated with Endoscopic Resection: A Case Report

Yong Woo Chung; Yong Cheol Jeon; Chang Hee Paik; Jong Pyo Kim; Dong Soo Han; Joo Hyun Sohn; Young Ha Oh; Yong Wook Park; Joon Soo Hahm

Angiodysplasia has been increasingly recognized as a major cause of gastrointestinal bleeding, responsible for approximately 6.0% of cases of lower GI bleeding (1). With the advent of colonoscopy and other radiologic techniques, angiodysplasia has been diagnosed frequently. At colonoscopy, typical angiodysplasia generally appears as a bright red, flat area with irregular borders. However, a new type of angiodysplasia, pedunculated angiodysplasia, with an appearance similar to that of pedunculated polyp, has been described in seven Japanese patients (2, 3). No similar case has been reported outside Japan. Here we report a case of pedunculated angiodysplasia which was treated successfully with endoscopic resection.

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