Increasing burden of biliary tract infection caused by extended-spectrum beta-lactamase-producing organisms in Korea: A nationwide population-based study.

BACKGROUND AND AIM: Biliary tract infections (BTIs) are a major cause of bacteremia. The prevalence of antibiotic-resistant pathogens in BTI patients is reported to be increasing. We used a nationwide database to evaluate the prevalence of, and risk factors for, BTIs caused by extended-spectrum beta-lactamase-producing organisms (ESBL-PO) in Korea. METHODS: Patients with a BTI diagnosis, an admission history, a history of a BTI-related procedure, and antibiotic use for ≥ 4 days between 2007 and 2016 were identified from the Health Insurance Review and Assessment Service database. A BTI treated with carbapenems (BTI-TC) was used as the surrogate for a BTI caused by ESBL-PO. We conducted a multivariate logistic regression analysis to determine the risk factors for BTI-TC. RESULTS: In total, 341 002 patients were enrolled. The overall percentage of BTI-TC among BTIs was 2.4%, with an increasing annual trend (P < 0.0001). The risk of acute cholangitis caused by ESBL-PO increased significantly in men, older patients, patients with comorbidities, patients with a history of a biliary procedure within the previous year, and patients with a history of antibiotic use within the previous 90 days. Regarding antibiotic use, the patients at highest risk were those previously prescribed carbapenems (adjusted odds ratio, 4.77; P < 0.0001). CONCLUSIONS: The prevalence of BTIs caused by ESBL-PO has increased during the last 10 years. Initial carbapenem therapy should be considered for elderly patients with acute cholangitis if they have had a previous biliary procedure and/or a history of carbapenem administration within the previous 90 days.

Imaging Findings of an Intraluminal Duodenal Diverticulum Associated with Adult Duodeno-Duodenal Intussusception and Recurrent Pancreatitis: A Case Report.

Intraluminal duodenal diverticulum (IDD) is a rare congenital abnormality, consisting of a sac-like mucosal lesion in the duodenum. Cases of IDD can present with gastrointestinal bleeding, duodenal obstruction, or pancreatitis. Here, we report a rare case of a 25-year-old female presenting with IDD complicated by duodeno-duodenal intussusception and recurrent pancreatitis. The diagnosis was based on findings from radiologic examinations (CT and MRI), upper gastrointestinal series (barium swallow), and gastroduodenofiberscopy. Laparoscopic excision of the presumed duodenal duplication was performed. The subsequent histopathologic evaluation of the excised sac revealed normal mucosa on both sides, but the absence of a proper muscle layer confirmed the diagnosis of IDD. Radiologic detection of a saccular structure in the second portion of the duodenum can indicate IDD with duodeno-duodenal intussusception as the lead point.

Sectional Analysis of Learning on the KAIST-Ewha Colonoscopy Simulation II.

The goal of this study is to validate the KAIST-Ewha Colonoscopy Simulation II as a training tool by examining the sectional learning curve of the trainees' performance on the simulation. Nine subjects including three fellows and six residents in the internal medicine participated in this study. All the subjects practiced the colonoscopy on the simulation until their performance surpasses the criteria preset by colonoscopy experts. Performance of the subjects during all the trials was measured in terms of eight performance indices and analyzed according to the colon segments. The results show that the trainees' skills significantly improved through training on the KAIST-Ewha Colonoscopy Simulation II. Particularly, most of the improvement appeared in the sigmoid and descending colon. On the other hand, there was little improvement in the ascending colon.

The Impact of Cholecystectomy on the Gut Microbiota: A Case-Control Study.

Cholecystectomy alters the bile flow into the intestine and the enterohepatic circulation of the bile acids; this may affect the gut microbiota. We assessed the gut microbiota composition of patients who had undergone cholecystectomy and compared with those who had not. From a cohort of 1463 adult participants who underwent comprehensive health screening examinations, 27 subjects who had undergone cholecystectomy (cholecystectomy group) and 81 age- and sex-matched subjects who had not (control group) were selected. Clinical parameters were collected and compared. Microbial composition was determined by 16S rRNA gene sequencing of DNA extracted from fecal samples. We evaluated differences in the overall microbial composition and in the abundance of taxa. The two groups were comparable with respect to clinical characteristics and laboratory results. The actual number of taxa observed in a sample (observed features) was significantly lower in the cholecystectomy group than in the control group (p = 0.042). The beta diversity of Jaccard distance index was significantly different between the two groups (p = 0.027). Blautia obeum and Veillonella parvula were more abundant in the cholecystectomy group. The difference in the diversity of the gut microbiota between the cholecystectomy and control groups was subtle. However, B. obeum and V. parvula, which have azoreductase activity, were more abundant in the cholecystectomy group. The impact of such changes in the gut microbiota on health remains to be determined.

Improvement of colonoscopy skills through simulation-based training.

The objective of this study is to determine whether targeted colonoscopy skills are acquired through simulation-based training using the KAIST-Ewha Colonoscopy Simulator II, and the acquired skills can be transferred to colonoscopy to actual patients. Eleven subjects consisting of six fellows and five residents participated in the study. The fellows and residents were divided into two groups, simulation-trained group and control group. Simulation-based training included practicing the targeted skills of colonoscopy using two training scenarios with different colon flexures and degrees of difficulty. The trainees were requested to practice until they reach all the established training goals. The both groups were evaluated during their colonoscopies to actual patients, which were performed under close supervision of colonoscopy experts. The results of this study show that the developed colonoscopy simulator is effective in teaching the targeted colonoscopy skills, and transferring those skills to actual colonoscopy.

Dyslipidemia and H pylori in gastric xanthomatosis.

AIM: To investigate the relationship among gastric xanthomatosis (GX), H pylori, dyslipidemia, and gastritis in Korea, a well-known H pylori endemic area. METHODS: A total of 771 patients who had undergone gastroduodenoscopy by one endoscopist were included in this study. Among them, 54 patients with GX were assessed for H pylori infection and their endoscopic characteristics and serum lipid profiles. The findings were compared with 54 age- and sex-matched control subjects without GX. RESULTS: The prevalence of GX was 7% (54/771) with no sex difference. GX was mainly single (64.8%) and located in the antrum (53.7%). The mean diameter was 7 +/- 3 mm. Mean body mass index (BMI) of patients with GX was 23.1 +/- 2.8 and no one was above 30. Compared with the controls, lipid profiles of GX group showed significantly lower HDL-cholesterol (48.8 +/- 12.3 vs 62.9 +/- 40.5, P = 0.028) and higher LDL-cholesterol (112.9 +/- 29.9 vs 95.9 +/- 22.4, P = 0.032). The level of total serum cholesterol, triglyceride and the existence of dyslipoproteinemia were not related to the presence of GX. However, GX showed a close relationship with endoscopically determined atrophic gastritis and histologic severity (24/53, 44.4% vs 8/54, 14.8%, P = 0.0082). H pylori infection and bile reflux gastritis were not significantly related with GX. CONCLUSION: The prevalence of GX is 7% and it may be an increasing entity in Korea. Moreover, dyslipidemia and atrophic gastritis are found to be related to GX, but H pylori infection is not.

Pancreatic abscess following scrub typhus associated with multiorgan failure.

Clinical severity of scrub typhus ranges from mild to fatal. Acute pancreatitis with abscess formation is a rare complication among patients with scrub typhus. This paper reports a case of scrub typhus in a 75 years old man with acute pancreatitis with abscess formation and multiorgan failure. Abdominal computed tomography showed multiple infected pancreatic pseudocysts with peri-pancreatic infiltration. Multiorgan failure was successfully treated with doxycycline, ceftriaxone, and supportive management. The pancreatic abscess was successfully drained percutaneously and the sizes of pseudocysts decreased remarkably.

Clinical evaluation of the KAIST-Ewha Colonoscopy Simulator II.

This paper presents clinical evaluation of the KAIST-Ewha Colonoscopy Simulator II that is extended from the previous version jointly developed by KAIST and Ewha Womans University. Realism validation was carried out twice before the clinical evaluation. Nine fellows and six residents participated in this part of clinical evaluation study, and they were divided into two groups, simulation-trained and control groups. The control group was assessed through five colonoscopies to actual patients under supervision before starting the traditional patient-based training. They will be assessed again after the regular training is over. The simulation-trained group is being trained with two specially designed training scenarios. The subjects in this group will be also assessed through five colonoscopies to actual patients after completing the training. The study is in progress, and this paper reports preliminary results of the study.

Non-clinical evaluation of the KAIST-Ewha Colonoscopy Simulator II.

This paper presents non-clinical evaluation of the KAIST-Ewha Colonoscopy Simulator II. Thirty one engineering-major students with no medical background were divided into two groups after they had been given instruction on colonoscopy and its operation. The baseline evaluation showed that both groups were equivalent in the level of the colonoscopy skills. The simulation-trained group underwent training until they passed all the performance criteria established by colonoscopy experts. Results of final evaluation showed that the simulation-trained group noticeably improved their skills.

Cytomegalovirus ileitis in an immunocompetent elderly adult.

Cytomegalovirus enteritis is most usually associated with patients positive for human immunodeficiency virus or immunosuppressed transplant patients. The gastrointestinal tract may be affected anywhere from the esophagus to the colon, but the small bowel involvement is rare. We report a case of cytomegalovirus ileitis in an immunocompetent adult, which was confirmed by histopathologic findings through colonoscopic biopsy.

A p53 genetic polymorphism of gastric cancer: difference between early gastric cancer and advanced gastric cancer.

AIM: To investigate the role of the polymorphism of p53 codon 72 in early gastric cancer (EGC) and advanced gastric cancer (AGC) in Korean patients. METHODS: DNA was extracted from blood samples of gastric cancer patients (n=291) and controls (n=216). In the p53 codon 72 genotypes were determined by PCR-RFLP. RESULTS: Patients with gastric cancer had a significantly higher frequency of the homozygous proline (Pro) allele than the control (P=0.032). Patients with AGC had a significantly higher frequency of the Arg/Arg (arginine) allele (P=0.038) than EGC and a similar Pro/Pro allele. The signet ring cell type had a higher frequency of the Pro/Pro allele than other types (P=0.031). The Pro/Pro genotype carries a 3.9-fold increased risk of developing gastric cancer (95% CI, 1.3-15.4, P=0.039) when compared to Arg/Arg and Arg/Pro genotypes and to develop EGC is a 5.25 fold increased risk (95% CI, 1.8-19.6, P=0.021). CONCLUSION: The Pro/Pro genotype of the p53 codon 72 polymorphism carries a higher risk for gastric cancer in general and is also associated with a much higher risk for EGC than AGC.

Centerline-based parametric model of colon for colonoscopy simulator.

This paper presents a centerline-based parametric model of colon for collision detection and visualization of the colon lumen for colonoscopy simulator. The prevailing marching cubes algorithm for 3D surface construction can provide a high resolution mesh of triangular elements of the colon lumen from CT data. But a well organized mesh structure reflecting the geometric information of the colon is essential to fast and accurate computation of contact between the colonoscope and colon, and the corresponding reflective force in the colonoscopy simulator. The colon is modeled as parametric arrangement of triangular elements with its surface along the centerline of the colon. All the vertices are parameterized according to the radial angle along the centerline, so that the triangles around the viewpoint can be found fast. The centerline-based parametric colon model has 75,744 triangular elements compared to 373,364 of the model constructed by the marching cubes algorithm.

Seroprevalence of Helicobacter pylori in female Vietnamese immigrants to Korea.

AIM: To investigate the seroprevalence of Helicobacter pylori (H. pylori) and its relationship to nutritional factors in female Vietnamese immigrants to Korea. METHODS: A total of 390 female immigrants from Vietnam and 206 Korean male spouses participated in the study. Blood samples from 321 female immigrants and 201 Korean male spouses were analyzed for H. pylori antibodies. Data on age, sex, alcohol consumption, smoking status, dietary nutritional factors and gastrointestinal symptoms were collected using questionnaires. The daily intakes of the following nutrients were estimated: energy, protein, niacin, lipid, fiber, calcium, iron, sodium, potassium, zinc, folate, cholesterol, and vitamins A, B1, B2, B6, C and E. RESULTS: The prevalence of H. pylori positivity was lower in the immigrants than in age-matched Korean females (55.7% vs 71.4%, respectively; P < 0.0001) and the domestic population of Vietnam. The prevalence of H. pylori positivity among married couples was 31.7% for both spouses. There were no statistically significant differences in the incidence of smoking, amount of alcohol consumed, or nutritional factors between the H. pylori-positive and negative groups. CONCLUSION: The prevalence of H. pylori positivity was lower among female Vietnamese immigrants than among Korean females. Nutritional factors did not differ between the H. pylori-positive and negative groups.

Associations between single nucleotide polymorphisms of MMP2, VEGF, and HIF1A genes and the risk of developing colorectal cancer.

UNLABELLED: The aim of this study was to investigate the association between the risk for colorectal cancer and single nucleotide polymorphisms (SNP) of matrix metalloproteinase-2 (MMP2) -1306C/T, vascular endothelial growth factor (VEGF) 936C/T and hypoxia inducible factor-1α (HIF1A) 1772C/T. PATIENTS AND METHODS: A total 50 colorectal cancer patients (46% women, mean age 68 ± 11 years) were enrolled. Healthy controls without evidence of cancer history or family cancer predispositions were frequency-matched to the cases by sex and age (±5 years). Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method and the genotype distribution and risk estimate were analyzed. The correlation between the genotypes and clinicopathological parameters (Dukes stage, phenotype, location, differentiation and size) among colorectal cancer patients were investigated. RESULTS: There was a significant association between colorectal cancer and T allele-bearing genotype distribution of HIF1A 1772C/T polymorphism (Odds ratio, OR=3.63, 95% confidence interval, CI = 1.08-12.18, p = 0.03 for CT and TT genotypes relative to CC genotype). In addition, when stratified by age, the association remained in patients older than 60 years old (OR = 13.60, 95% CI = 1.63-113.24, p = 0.01). However, there was no association between the genotypes of the MMP2, VEGF and HIF1A SNP and clinicopathological parameters of colorectal cancer. CONCLUSION: There is a significant association between the HIF1A 1772C/T SNP and the risk of developing colorectal cancer, especially in individuals older than 60 years.

Reinfection rate and endoscopic changes after successful eradication of Helicobacter pylori.

AIM: To determine the long-term outcomes regarding reinfection with Helicobacter pylori (H. pylori) and endoscopic changes after successful H. pylori eradication. METHODS: From June 1994 to January 2007, 186 patients (M:F = 98:88; mean age 50.0 +/- 11.4 years), in whom H. pylori had been successfully eradicated, were enrolled. The mean duration of follow up was 41.2 +/- 24.0 mo. RESULTS: H. pylori reinfection occurred in 58 patients (31.2%). The average annual reinfection rate was 9.1% per patient year. No recurrence of peptic ulcer was detected at the follow up endoscopy. There were no significant differences between the H. pylori eradication regimens for the reinfection rate and no significant differences in endoscopic findings between the H. pylori-recurred group and the H. pylori-cured group. CONCLUSION: The reinfection rate in Korea is 9.1% which represents a decreasing trend. There was no relationship between H. pylori infection status and changes in endoscopic findings. There was also no recurrence or aggravation of ulcers.

Nevus-like appearance of primary malignant melanoma of the esophagus.

The primary malignant melanoma of the esophagus (PMME) is a rare malignant disease, accounting for only 0.1-0.2% of all esophageal neoplasms, and the majority of the patients are diagnosed at advanced stages with poor prognosis. We present here a case of 56-year-old woman with epigastric pain and her endoscopic finding revealed several flat and black pigmented mucosal lesions within the distal portion of the esophagus which looked like flat nevus. The histopathology and immunohistochemical profile of the tissue specimens were diagnostic of malignant melanoma.

Haplotype analysis of the matrix metalloproteinase-9 gene associated with advanced-stage endometriosis.

OBJECTIVE: To investigate whether the -1562C>T, R279Q, P574R, and R668Q polymorphisms of the matrix metalloproteinase-9 (MMP-9) gene are related to endometriosis. DESIGN: Case-control study. SETTING: University-based hospital in Korea. PATIENT(S): Patients with endometriosis stage III/IV (n = 225) who underwent pelvic surgery and controls (n = 198) with no endometriosis in a Korean population. INTERVENTION(S): Peripheral blood samples were collected by venipuncture. MAIN OUTCOME MEASURE(S): Frequencies of genotypes and haplotypes were compared with the risk of endometriosis including -1562C>T, R279Q, P574R, and R668Q polymorphisms of MMP-9. RESULT(S): In the two-locus haplotype analyses using the four single nucleotide polymorphisms (SNPs), an increase in the distribution of the R279Q/P574R (2678G>A/4859C>G) (AC haplotype: odds ratio [OR] = 3.180, 95% confidence interval [CI] = 1.956-5.170; GG haplotype: OR = 4.374, 95% CI = 2.376-8.053) and -1562C>T/R668Q (-1562C>T/5546G>A) (CA haplotype: OR = 3.280, 95% CI = 1.406-7.653) haplotypes was significantly associated with endometriosis. By contrast, the risk of endometriosis was not associated with the individual SNPs studied. CONCLUSION(S): These findings suggest that haplotype analysis was more informative than SNP analysis. The haplotypes in the MMP-9 gene may correlate with the progression of endometriosis, and further study of these variations might improve our understanding of the pathogenesis of endometriosis.

Haptic interface of the KAIST-Ewha colonoscopy simulator II.

This paper presents an improved haptic interface for the Korea Advanced Institute of Science and Technology Ewha Colonoscopy Simulator II. The haptic interface enables the distal portion of the colonoscope to be freely bent while guaranteeing sufficient workspace and reflective forces for colonoscopy simulation. Its force-torque sensor measures the profiles of the user. Manipulation of the colonoscope tip is monitored by four deflection sensors and triggers computations to render accurate graphic images corresponding to the rotation of the angle knob. Tack sensors are attached to the valve-actuation buttons of the colonoscope to simulate air injection or suction as well as the corresponding deformation of the colon. A survey study for face validation was conducted, and the result shows that the developed haptic interface provides realistic haptic feedback for colonoscopy simulations.