Hae Yeon Kang

Progression of atrophic gastritis and intestinal metaplasia drives Helicobacter pylori out of the gastric mucosa

This study was performed to evaluate the implication of anti-H. pylori IgG positivity when CLOtest, histological test, and culture in the antrum and body are all negative, and to find out the specific disease category that is more affected by the hostile relationship of atrophic gastritis and intestinal metaplasia (IM) with H. pylori. Four hundred thirty-six patients (84 controls, 69 with duodenal ulcer, 96 with benign gastric ulcer, 43 with dysplasia, 144 with gastric cancer), who had not received any eradication therapy, were divided into three groups according to H. pylori test: CLOtest or histological H. pylori-positive group (group A; 294 cases), only anti-H. pylori IgG-positive group (group B; 62 cases), and anti-H. pylori IgG-negative group (group C; 80 cases). The grade of neutrophil and monocyte infiltration, atrophic gastritis, and IM was compared according to the updated Sydney system classification. Neutrophil and monocyte infiltrations were significantly severe in the group A. In contrast, the grade of atrophic gastritis and IM in the antrum was significantly higher in group B than the other two groups, A or C. When patients were divided according to the disease outcome in each group, the grade of IM in the body was statistically higher only in the patients with cancer or dysplasia in group B. These results suggest that anti-H. pylori IgG positivity with all negative invasive H. pylori tests represents past infection with H. pylori rather than a false negative, especially in the case of dysplasia and gastric cancer.

Effect of annual endoscopic screening on clinicopathologic characteristics and treatment modality of gastric cancer in a high‐incidence region of Korea

We investigated risk factors for gastric cancer (GC) and effect of annual endoscopic screening on detection and treatment modality of GC. Asymptomatic adults who underwent upper endoscopy during health checkups at Seoul National University Hospital Healthcare System Gangnam Center were enrolled. We compared clinicopathologic characteristics of GC according to screening interval (repeated vs. infrequent, annual vs. biennial). After age‐ and sex‐matching, relative risk was computed by hazard ratio (HR) using Cox proportional regression with multivariate adjustment. Of the 58,849 subjects who received screening endoscopy, 277 (0.47%) were found to have GC. Intestinal type comprised 55.4% (102/184) followed by diffuse type (n = 65, 35.3%). Age ≥50 years, family history and smoking independently increased the risk of GC for both types, whereas male gender [HR = 4.81, 95% confidence interval (CI): 2.72–8.03] and intestinal metaplasia (IM) (HR = 10.87, 95% CI: 3.36–22.30) were significant predictors for intestinal type only. Proportion of early gastric cancer (EGC) was 98.6% (71/72) in annual screening group and 80.7% (46/57) in biennial screening group (p < 0.01). In the former, tumor size was smaller (1.7 ± 1.3 vs. 2.3 ± 1.8 cm; p < 0.01] and proportion of intramucosal cancer was larger (75.0 vs. 56.1%; p = 0.04). Endoscopic resection was performed more frequently in annual screening group (56.9 vs. 33.3%; p = 0.02). IM along with male gender and older age was a strong risk factor for intestinal type GC. Annual screening group improved detection of early‐stage and endoscopically treatable GC suggesting that intensive screening and surveillance may be useful for high‐risk subpopulations with epidemiologic risk factors or premalignant lesions such as IM.

Comparison of detection and miss rates of narrow band imaging, flexible spectral imaging chromoendoscopy and white light at screening colonoscopy: a randomised controlled back-to-back study

Objective Virtual chromoendoscopy (CE) is expected to enhance adenoma yield and reduce variation in performance between colonoscopists. This study aimed to compare the efficacy of narrow band imaging (NBI), flexible spectral imaging CE (FICE) and white light (WL) colonoscopy and their impact for less experienced endoscopists. Methods We performed a randomised tandem colonoscopy trial controlling for withdrawal time and bowel preparation. Average-risk adults undergoing screening colonoscopy were enrolled and randomly assigned to first withdrawal with one of the three imaging modalities (NBI (NBI-WL group), FICE (FICE-WL group) and WL (WL-WL group)). Eight colonoscopists were categorised into expert and non-expert subgroups. Results 1650 subjects (mean age 51.4 years, 63.9% men) were included (550 in each group). Compared with WL, neither NBI nor FICE increased the mean number of adenomas detected per patient (0.37 vs 0.35 and 0.36; p=0.591) or the percentage of patients with adenoma (25.3% vs 24.5% and 23.6%; p=0.753). For all three modalities, expert subgroups had higher yields of adenomas than non-expert subgroups. Learning curves were observed only for non-expert subgroups with all three modalities. The percentage of missed adenomas did not differ between the three groups (20.8% by WL vs 22.9% by NBI and 26.0% by FICE, p=0.300) and was not affected by endoscopists’ expertise. Conclusions Neither NBI nor FICE improved adenoma detection or miss rates, with no difference in diagnostic efficacy between the two systems. Virtual CE had no additional benefits over WL for non-experts. Clinical trial registration number: KCT0000570.

Incidence and Management of Colonoscopic Perforations in Korea

Background and Aim: Despite the low incidence of perforation after endoscopic procedures in the colon, the increasing use of these procedures is likely to cause a commensurate increase in such problems. This study was undertaken to determine the incidence of iatrogenic perforation of the colon, to define clinical characteristics, and to assess the management of these complications. Methods: A retrospective review of the medical records was performed for all patients with iatrogenic colon perforations after endoscopy between January 2000 and June 2007. Results: Over this 7-year study period, a total of 20,660 sigmoidoscopies, 17,102 colonoscopies, and 6,772 therapeutic procedures were performed, and 53 (0.12%) perforations were determined to be related to endoscopy. A diagnostic procedure was undertaken in 26 of these 53 perforation cases (perforation rate, 0.07%; 1 per 1,452 procedures), and a therapeutic procedure in the remaining 27 (perforation rate, 0.40%; 1 per 251 procedures). Nineteen patients (36%) were treated conservatively, and the remaining 34 (64%) required surgical management. Endoscopic clipping was performed in 9 patients, and conservative treatment was possible in 7 patients with successful closure. No procedure-related mortality occurred. Conclusions: Endoscopic repair of iatrogenic colon perforations with clips could reduce immediate operative intervention rates.

Helicobacter pylori seropositivity in diabetic patients is associated with microalbuminuria

AIM To investigate the relationship between Helicobacter pylori (H. pylori) seropositivity and the presence of microalbuminuria. METHODS Between December 2003 and February 2010, asymptomatic individuals who visited the Seoul National University Healthcare System Gangnam Center for a routine check-up and underwent tests for H. pylori immunoglobulin G antibodies and urinary albumin to creatinine ratio (UACR) were included. All study subjects completed a structured questionnaire, anthropometric measurements and laboratory tests. Anti-H. pylori immunoglobulin G was identified using an enzyme-linked immunosorbent assay kit. A random single-void urine sample, collected using a clean-catch technique, was obtained to determine the UACR. The presence of microalbuminuria was defined as a UACR from 30 to 300 μg/mg. The presence of diabetes mellitus (DM) was defined as either a fasting serum glucose level greater than or equal to 126 mg/dL or taking anti-diabetic medication. Multiple logistic regression analysis was performed to identify the risk factors. The dependent variable was microalbuminuria, and the independent variables were the other study variables. RESULTS A total of 2716 subjects (male, 71.8%; mean age, 54.9 years) were included. Among them, 224 subjects (8.2%) had microalbuminuria and 324 subjects (11.9%) had been diagnosed with DM. Subjects with microalbuminuria had a significantly higher H. pylori seropositivity rate than subjects without microalbuminuria (60.7% vs 52.8%, P = 0.024). Multivariate analysis after adjustment for age, body mass index (BMI), waist circumference, and glucose and triglyceride levels showed that H. pylori seropositivity was significantly associated with microalbuminuria [odds ratio (OR), 1.40, 95% CI, 1.05-1.89, P = 0.024]. After the data were stratified into cohorts by glucose levels (≤ 100 mg/dL, 100 mg/dL < glucose < 126 mg/dL, and ≥ 126 mg/dL or history of DM), H. pylori seropositivity was found to be significantly associated with microalbuminuria in diabetic subjects after adjusting for age, BMI and serum creatinine level (OR, 2.21, 95% CI, 1.20-4.08, P = 0.011). In addition, the subjects were divided into five groups. Those without microalbuminuria (an UACR of < 30 μg/mg) were divided into four groups in accordance with their UACR values, and subjects with microalbuminuria comprised their own group. Notably, H. pylori seropositivity gradually increased with an increase in UACR (P = 0.001) and was highest in subjects with microalbuminuria (OR, 2.41, 95% CI, 1.14-5.11). This suggests that H. pylori seropositivity is positively associated with microalbuminuria in diabetic subjects. CONCLUSION H. pylori seropositivity was independently associated with microalbuminuria, and the prevalence of H. pylori seropositivity was associated with the severity of UACR in diabetic subjects.

Risk of progression for incidental small subepithelial tumors in the upper gastrointestinal tract.

BACKGROUND AND STUDY AIMS Subepithelial tumor is a relatively common finding in upper gastrointestinal endoscopy. This study aimed to evaluate the natural course of incidentally detected small subepithelial tumors in the upper gastrointestinal tract and to analyze risk factors for increase in the size of such tumors. PATIENTS AND METHODS Medical records of 1684 patients with subepithelial tumors in the upper gastrointestinal tract incidentally detected between 2004 and 2013 were retrospectively reviewed. If serial follow-up endoscopy showed significant size increase, endoscopic or surgical resection was recommended because of possibility of malignant change. RESULTS 954 participants with subepithelial tumors underwent serial upper gastrointestinal endoscopy for a period > 6 months. Initial mean size of subepithelial tumors was 8.7 mm (range 1 - 35 mm). During a mean follow-up of 47.3 months (range 6 - 118 months), lesion size was unchanged in 920 participants (96.4 %), and in 34 participants (3.6 %) lesions had increased at least 25 % in diameter (mean increment 6.2 mm, range 2 - 15 mm). Subepithelial tumors with overlying mucosal changes (hyperemia, erosion, or ulcer) had a significantly higher risk of increasing in size (odds ratio [OR] = 3.61, 95 % confidence interval [95 %CI] 1.06 - 12.28). Growth rates (size increment per year) for enlarging lesions were significantly correlated with initial size (r = 0.44, P = 0.009). CONCLUSIONS Most incidentally detected small subepithelial tumors in the upper gastrointestinal tract showed no size change during follow-up. Thus, regular follow-up with serial endoscopy may be sufficient for small subepithelial tumors (< 2 cm) with intact overlying mucosa.

Thirty-day mortality after percutaneous gastrostomy by endoscopic versus radiologic placement: a systematic review and meta-analysis

Background/Aims A percutaneous gastrostomy can be placed either endoscopically (percutaneous endoscopic gastrostomy, PEG) or radiologically (radiologically-inserted gastrostomy, RIG). However, there is no consistent evidence of the safety and efficacy of PEG compared to RIG. Recently, 30-day mortality has become considered as the most important surrogate index for evaluating the safety and efficacy of percutaneous gastrostomy. The aim of this meta-analysis was to compare the 30-day mortality rates between PEG and RIG. Methods Major electronic databases (MEDLINE, Embase, Scopus, and Cochrane library) were queried for comparative studies on the two insertion techniques of gastrostomy among adults with swallowing disturbance. The primary outcome was the 30-day mortality rate after gastrostomy insertion. Forest and funnel plots were generated for outcomes using STATA version 14.0. Results Fifteen studies (n=2,183) met the inclusion criteria. PEG was associated with a lower risk of 30-day mortality after tube placement compared with RIG (odds ratio, 0.60; 95% confidence interval [CI], 0.38–0.94; P=0.026). The pooled prevalence of 30-day mortality of PEG was 5.5% (95% CI, 4.0%–6.9%) and that of RIG was 10.5% (95% CI, 6.8%–14.3%). No publication bias was noted. Conclusions The present meta-analysis demonstrated that PEG is associated with a lower probability of 30-day mortality compared to RIG, suggesting that PEG should be considered as the first choice for long-term enteral tube feeding. Further prospective randomized studies are needed to evaluate and compare the safety of these two different methods of gastrostomy.

Angioimmunoblastic T-Cell Lymphoma Mimicking Crohn’s Disease

Angioimmunoblastic T-cell lymphoma (AITL) is a rare, systemic lymphoproliferative disorder that accounts for approximately 1% of all non-Hodgkins lymphomas [1]. AITL typically presents as generalized lymphadenopathy, usually accompanied by systemic symptoms, such as, fever, malaise, and weight loss [2, 3], but primary gastrointestinal involvement is very rare [4]. In addition, it is difficult for clinicians to confirm lymphoma involving the gastrointestinal tract, based only on endoscopic findings and/or light microscopic findings [5]. We report a case of AITL that presented with chronic diarrhea and generalized weakness. The preliminary diagnosis in this case was Crohns disease, and the final diagnosis was delayed because of the unusual presentation.

The Relationship Between Colonoscopy Procedure Order and Adenoma Detection Rates: A Prospective Study.

Goals: The aim of this study was to prospectively assess the effects of the order of colonoscopic procedures and other possible factors on the adenoma detection rate (ADR). Background: There have been conflicting studies regarding the timing or order of a colonoscopy and its ability to detect adenomas. Study: Between March 2011 and July 2011, consecutive colonoscopies were prospectively performed by 7 board-certified staff endoscopists at the Seoul National University Hospital Healthcare System Gangnam Center. The primary outcome was the overall ADR according to the procedure order of the colonoscopies, and the secondary outcome was the identification of other possible factors influencing the ADR. Results: A total of 1908 colonoscopies were analyzed. The detection rate was 56.5% for all polyps and 37.3% for adenomas. The ADR increased as the performance order of the colonoscopy increased and was highest for the third procedure (43.4%). However, the ADR of the remaining procedures, including later procedures, was similar throughout the workday. In the multivariable analysis, the ADR was significantly associated with older age, male sex, high body mass index, personal history of colorectal polyps, long withdrawal time, and an experienced endoscopist. However, the colonoscopy procedure order was not significantly associated with the ADR. Conclusions: The ADR was stable according to the procedure order for the later procedures of the workday in a setting of moderate daily procedure volumes. The withdrawal time and experience level of the endoscopist were more important than the procedure order in detecting adenomas by colonoscopy.

Effect of Helicobacter pylori Eradication According to the IL-8-251 Polymorphism in Koreans

Previous studies suggested that polymorphisms of proinflammatory cytokine genes are important host genetic factors in Helicobacter pylori infection. The present study evaluated whether IL-8-251 polymorphism affected H. pylori eradication rate and to investigate the effect of H. pylori eradication on angiogenesis and the inflammatory process according to the IL-8-251 polymorphism. A total of 250 H. pylori-positive patients treated by endoscopic resection of the gastric neoplasm were classified into 3 groups (134 H. pylori-eradicated group, 19 H. pylori-eradication failure group, and 97 H. pylori-infected group). H. pylori status, histology, and angiogenic factor levels were evaluated at baseline, 6 months, and 18 months. H. pylori eradication rate was 92.9% in AA genotype, 85.7% in AT genotype and 88.4% in TT genotype (P value = 0.731). Elevated IL-8 and matrix metalloproteinase-9 concentrations in H. pylori-infected gastric mucosa were reversible by successful eradication of H. pylori, independent of the IL-8-251 polymorphism. It is suggested that elevated IL-8 and MMP-9 concentrations in H. pylori-infected gastric mucosa are altered significantly after successful eradication and these conditions continue for 18 months. However, IL-8-251 polymorphism does not affect H. pylori eradication rate and the sequential changes of related angiogenic factors after H. pylori eradication in Koreans.