The Usefulness of Esophageal Baseline Impedance Levels for the Diagnosis of Nonerosive Reflux Disease and the Proper Time for Measurement in Endoscopy-negative Korean Patients With Esophageal or Supraesophageal Symptoms

Background/Aims@#Low baseline impedance levels (BILs) have been suggested to be evidence of GERD. The aim of this study is to investigate the usefulness of esophageal BILs for the diagnosis of nonerosive reflux disease (NERD) and the proper time for measurement in endoscopy-negative Korean patients with esophageal or supraesophageal symptoms. @*Methods@#Endoscopy-negative patients with esophageal or supraesophageal symptoms who underwent esophageal multichannel intraluminal impedance-pH monitoring were included. BILs were measured in the proximal and distal esophagus around 10 minutes before meals, 10 minutes and 30 minutes after meals, 30 minutes before the start of nighttime sleep, and 30 minutes and 60 minutes after the start of nighttime sleep. @*Results@#A total of 104 patients were included in the study. Distal and proximal esophageal BILs were decreased after meal ingestion. The BILs of the distal esophagus were significantly lower at all time points in the NERD group, but not in the reflux hypersensitivity (RH) group, compared with the functional group. The area under the receiver operating characteristic curve for the diagnosis of NERD was significant at all time points, but that for the diagnosis of RH was not. The cut-off value of 2375 Ω or 2125 Ω measured around 30 minutes before or 60 minutes after the start of nighttime sleep, respectively, were appropriate for the diagnosis of NERD. @*Conclusion@#The BILs of the distal esophagus measured at time points before or after the start of nighttime sleep appear to be useful for the diagnosis of NERD, but not for the diagnosis of RH, in endoscopy-negative Korean patients with esophageal or supraesophageal symptoms.

Fecal Microbiota Alterations and Small Intestinal Bacterial Overgrowth in Functional Abdominal Bloating/Distention

Background/Aims@#The pathophysiology of functional abdominal bloating and distention (FABD) is unclear yet. Our aim is to compare the diversity and composition of fecal microbiota in patients with FABD and healthy individuals, and to evaluate the relationship between small intestinal bacterial overgrowth (SIBO) and dysbiosis. @*Methods@#The microbiota of fecal samples was analyzed from 33 subjects, including 12 healthy controls and 21 patients with FABD diagnosed by the Rome IV criteria. FABD patients underwent a hydrogen breath test. Fecal microbiota composition was determined by 16S ribosomal RNA amplification and sequencing. @*Results@#Overall fecal microbiota composition of the FABD group differed from that of the control group. Microbial diversity was significantly lower in the FABD group than in the control group. Significantly higher proportion of Proteobacteria and significantly lower proportion of Actinobacteria were observed in FABD patients, compared with healthy controls. Compared with healthy controls, significantly higher proportion of Faecalibacterium in FABD patients and significantly higher proportion of Prevotella and Faecalibacterium in SIBO (+) patients with FABD were found. Faecalibacterium prausnitzii, was significantly more abundant, but Bacteroides uniformis and Bifidobacterium adolescentis were significantly less abundant in patients with FABD, compared with healthy controls. Significantly more abundant Prevotella copri and F. prausnitzii, and significantly less abundant B. uniformis and B. adolescentis were observed in SIBO (+) patients, compared with healthy controls. @*Conclusion@#The fecal microbiota profiles in FABD patients are different from those in healthy controls, particularly in SIBO (+) patients, suggesting a role of gut microbiota in the pathogenesis of FABD.

Comparison of Effectiveness between Abdominal Vibration Stimulation and Walking Exercise for Bowel Cleansing before Therapeutic Colonoscopy

Background/Aims@#Adequate bowel preparation is important for successful colonoscopy. We aimed to evaluate the clinical feasibility and effectiveness of abdominal vibration stimulation in bowel preparation before therapeutic colonoscopy. @*Methods@#A single center, prospective, randomized, investigator-blinded study was performed between January 2016 and December 2016. Patients for therapeutic colonoscopy were prospectively enrolled and assigned to either the vibrator group or walking group. Patients who refused to participate in this study as part of the experimental group consented to register in the control group instead. During the preparation period, patients assigned to the walking group walked ≥3,000 steps, whereas those assigned to the vibrator group received abdominal vibrator stimulation and restricted walking. All patients received the same colon cleansing regimen: 4-L split-dose polyethylene glycol (PEG) solution. @*Results@#Three hundred patients who received PEG solution for therapeutic colonoscopy were finally enrolled in this study (n=100 per group). Bowel cleansing with abdominal vibration stimulation showed almost similar results to that with walking exercise (Boston Bowel Preparation Scale score for the entire colon: vibrator vs walking vs control, 7.38±1.55 vs 7.39±1.55 vs 6.17±1.15, p<0.001). There were no significant differences between the vibrator group and walking group regarding instances of diarrhea after taking PEG, time to first diarrhea after taking PEG, total procedure time, and patient satisfaction. @*Conclusions@#This study indicates that, compared with conventional walking exercise, abdominal vibration stimulation achieved similar rates of bowel cleansing adequacy and colonoscopy success without compromising safety or patient satisfaction.

Impact of previous metronidazole exposure on metronidazole-based second-line quadrupletherapy for Helicobacter pylori infection

Background/Aims@#The negative effects on the eradication success of Helicobacter pylori infection after previous exposure to macrolides, including clarithromycin on clarithromycin-based first-line therapy have been demonstrated. However,whether this is true for metronidazole-based second-line quadruple therapy remains unclear. We investigated the relationship between past administration of metronidazole and the failure of metronidazole-based second-line quadruple therapy in patients with H. pylori infection. Methods: Patients over 20 years of age who were diagnosed with H. pylori infection between January 1998 and March 2016 were enrolled in this study. The relationship between the clinical parameters and the results of a C13-urea breath test after metronidazole-based second-line quadruple therapy was analyzed in patients for whom clarithromycin-based triple therapy failed to eradicate H. pylori . @*Results@#The H. pylori eradication failure rate was significantly higher in patients with a history of metronidazole use than in patients without a history of metronidazole use ( p = 0.011). Multivariable analysis showed that the odds ratio of previous metronidazole use for eradication failure was 3.468 (95% confidence interval,1.391 to 8.649; p = 0.008). In the subgroup analysis of patients with a history of metronidazole use, the duration of metronidazole use and interval between its use and eradication therapy did not significantly affect H. pylori eradication failure. @*Conclusions@#Previous exposure to metronidazole was a significant risk factor for treatment failure of metronidazole-based second-line quadruple therapy; therefore, this should be considered when establishing a treatment strategy for patients with H. pylori infection.

Effect of PTEN Polymorphism on the Development of Hepatitis B Virus-associated Hepatocellular Carcinoma

BACKGROUND/AIMS: Phosphatase and tensin homolog (PTEN) is a known tumor suppressor gene that is downregulated in hepatocellular carcinoma (HCC). Here, we investigated the association between single nucleotide polymorphisms (SNPs) of PTEN and HCC development in patients with hepatitis B virus (HBV) infection. METHODS: Six SNPs of PTEN at positions rs1234221, rs1903860, rs1234220, rs1903858, rs2299941, and rs17431184 were analyzed in a development population (417 chronic HBV carriers without HCC and 281 chronic HBV carriers with HCC). PTEN rs1903858, rs1903860, and rs2299941 SNPs were further assessed for the development of HCC in a validation population of 200 patients with HBV-related liver cirrhosis. RESULTS: In the development population, PTEN rs1903860 C allele, rs1903858 G allele, and rs2299941 G allele were associated with a low risk of HCC. The haplotype A-T-A-A-A was associated with an increased risk of HCC (recessive model; odds ratio=2.277, 95% confidence interval [CI] =1.144-4.532, P=0.019). In the validation population, PTEN rs2299941 G allele was the only significant protective genetic polymorphism related to HCC development after adjustment for age and sex (hazard ratio=0.582, 95% CI =0.353–0.962, P=0.035). CONCLUSIONS: These findings suggest that genetic polymorphisms in PTEN may affect HCC development in patients with chronic HBV infection.

A Proposal for Modification of the Barcelona Clinic Liver Cancer Staging System Considering the Prognostic Implication of Performance Status

BACKGROUND/AIMS: Barcelona Clinic Liver Cancer (BCLC) C stage demonstrates considerable heterogeneity because it includes patients with either symptomatic tumors (performance status [PS], 1–2) or with an invasive tumoral pattern reflected by the presence of vascular invasion (VI) or extrahepatic spread (EHS). This study aimed to derive a more relevant staging system by modification of the BCLC system considering the prognostic implication of PS. METHODS: A total of 7,501 subjects who were registered in the Korean multicenter hepatocellular carcinoma (HCC) registry database from 2008 to 2013 were analyzed. The relative goodness-of-fit between staging systems was compared using the Akaike information criterion (AIC) and integrated area under the curve (IAUC). Three modified BCLC (m-BCLC) systems (#1, #2, and #3) were devised by reducing the role of PS. RESULTS: As a result, the BCLC C stage, which includes patients with PS 1–2 without VI/EHS, was reassigned to stage 0, A, or B according to their tumor burden in the m-BCLC #2 model. This model was identified as the most explanatory and desirable model for HCC staging by demonstrating the smallest AIC (AIC=70,088.01) and the largest IAUC (IAUC=0.722), while the original BCLC showed the largest AIC (AIC=70,697.17) and the smallest IAUC (IAUC=0.705). The m-BCLC #2 stage C was further subclassified into C1, C2, C3, and C4 according to the Child-Pugh score, PS, presence of EHS, and tumor extent. The C1 to C4 subgroups showed significantly different overall survival distribution between groups (p<0.001). CONCLUSIONS: An accurate and relevant staging system for patients with HCC was derived though modification of the BCLC system based on PS.

Effects of the Administration of Probiotics on Fecal Microbiota Diversity and Composition in Healthy Individuals

BACKGROUND/AIMS: Probiotics are expected to modify the composition of gut microbiota. We aimed to investigate the changes in the composition and diversity of gut microbiota by the administration of probiotics in healthy individuals. METHODS: Twelve healthy volunteers with age range of 30–42 years provided baseline fecal samples. Subsequently, they took commercially available probiotic capsules (a mixture for Bifidobacterium, Lactobacillus, and Enterococcus) for 4 weeks. Fecal samples were collected at 4 weeks of administration and 2 weeks after the stop of administration. Fecal microbiota was analyzed via 16S ribosomal RNA gene sequencing. RESULTS: The mean Shannon index was not significantly altered by the 4-week administration of probiotics (4.365 vs 4.556, P > 0.05). The proportion of Bacteroidetes, Actinobacteria, Firmicutes, and Proteobacteria was not significantly changed by the 4-week administration of probiotics. At the genus level, the proportions of Lactobacillus (2.138% vs 2.773%, P = 0.028) and Enterococcus (0.022% vs 2.758%, P = 0.004) significantly increased 4 weeks after the administration of probiotics, but reduced 2 weeks after the stop of administration (2.773% vs 3.292%, P = 0.064 and 2.758% vs 0.001%, P = 0.001). CONCLUSIONS: The diversity of fecal microbiota is not significantly affected by 4 weeks of probiotics administration. The proportion of fecal microbiota at the genus level is significantly altered by the administration of probiotics. However, this effect does not seem to last long, probably because of homeostasis or dietary influence.

Negative Histology after Endoscopic Resection: An Endoscopist's Aspect / 대한Helicobacter연구학회지

Endoscopic submucosal dissection (ESD) is accepted as the standard treatment for gastric epithelial dysplasia or early gastric cancer because it enables curative en bloc resection and complete histopathological assessment of the specimen. However, occasionally, a tumorous lesion may not be detected, and histopathological discrepancies can occur after ESD. Reportedly, the prevalence of negative histopathological results after endoscopic resection is 2.0~4.4%. Negative histopathological results after endoscopic resection are commonly attributable to complete removal of the lesion via an endoscopic forceps biopsy (EFB) at the time of the initial diagnostic endoscopic examination, an initial histopathological overestimation of the EFB specimen, and incorrect localization of the original tumor with subsequent ESD performed at a wrong site. A small tumor size and surface area are known to be significant endoscopic predictors of negative histopathological results after ESD. Therefore, clinicians should be mindful of the fact that negative histopathological findings observed after endoscopic resection warrant a comprehensive review of all pre-ESD data and an adequate follow-up to determine the cause of these findings and to detect any possibility of local recurrence.

Can water insufflation and carbon dioxide overcome the difficulties of colonoscope insertion?

No abstract available.

Prediction of Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis Using 4-Hour Post-Endoscopic Retrograde Cholangiopancreatography Serum Amylase and Lipase Levels

Early post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP) prediction may allow safe same-day outpatients discharge after ERCP and earlier proper management. This study aimed to assess the usefulness of the 4-hour post-ERCP serum amylase and lipase levels for PEP early prediction and to investigate predictive cut-off values for 4-hour post-ERCP serum amylase and lipase levels for safe discharge and urgent initiation of resuscitation. The data of 516 consecutive patients with native papilla who underwent ERCP between January 2013 and August 2014 were retrospectively reviewed. Serum amylase and lipase levels were measured before, and 4 and 24 hours after ERCP. PEP occurred in 16 (3.1%) patients. The receiver-operator characteristic curve for 4-hour post-ERCP serum amylase and lipase levels showed that the areas under the curve were 0.919 and 0.933, respectively, demonstrating good test performances as predictors for PEP (both P values 1.5 × the upper limit of reference (ULR) was found useful for PEP exclusion with a sensitivity of 93.8%, while 4 × ULR was found useful to guide preventive therapy with the best specificity of 93.2%. Similarly, the lipase level 2 × ULR showed best sensitivity, while 8 × ULR had the best specificity. Logistic regression analysis showed that 4-hour post-ERCP amylase level > 4 × ULR, lipase level > 8 × ULR, precut sphincterotomy, and pancreatic sphincterotomy were significant predictors for PEP. In conclusion, 4-hour post-ERCP amylase and lipase levels are useful early predictors of PEP that can ensure safe discharge or prompt resuscitation after ERCP.

Non-steroidal anti-inflammatory drug-induced enteropathy

Non-steroidal anti-inflammatory drugs (NSAIDs) are well known to be associated with serious upper gastrointestinal complications, such as peptic ulcer, bleeding, perforation, and obstruction. Recently, attention has been mainly focused on the small bowel injuries caused by NSAIDs, and new endoscopic techniques such as capsule endoscopy and double balloon endoscopy can help in detecting such injuries. This article reviewed the epidemiology, pathogenesis, clinical manifestations, diagnosis, and treatment of small bowel injuries caused by NSAIDs. Small bowel injures by NSAIDs might occur with a similar frequency and extent as those observed in the upper gastrointestinal tract. The pathogenesis of NSAID-induced enteropathy is complex and not clearly understood. The various lesions observed in the small bowel, including petechiae, reddened folds, loss of villi, erosions, and ulcers can be detected by capsule endoscopy. A drug that could prevent or treat NSAID-induced enteropathy has not yet been developed. Therefore, further investigations should be performed to elucidate the pathogenesis of such enteropathy and develop suitable preventive and treatment strategies.

Recurrent Stent Thrombosis in a Patient with Antiphospholipid Syndrome and Dual Anti-Platelet Therapy Non-Responsiveness

Antiphospholipid syndrome (APS), the most common acquired hypercoagulable condition, is diagnosed by persistent presence of antiphospholipid antibodies and episodes of vascular thrombosis. It may be an important predisposing factor for stent thrombosis, resulting in poor outcomes. Also, anti-platelet therapy non-responsiveness is associated with stent thrombosis. We report a case of a 39-year-old man who after undergoing successful percutaneous coronary intervention for significant coronary artery disease suffered repeated stent thrombosis events leading to ST-segment elevation myocardial infarction. Eventually, he underwent coronary artery bypass surgery because of uncontrolled thrombosis and was diagnosed as having APS and dual antiplatelet therapy non-responsiveness.

A Case of Nutritional Osteomalacia in Young Adult Male

Vitamin D is an important hormone that can be a role of bone and calcium metabolism in the human organ. Thus, vitamin D deficiency could contribute to the severity of metabolic bone disease. The osteomalacia, one of the metabolic bone diseases, is the softening of the bones caused by defective bone mineralization secondary to inadequate amounts of available phosphorus and calcium. We experienced a case of osteomalacia presented with walking disturbance, 30 year-old young aged man, caused by vitamin D deficiency due to strict vegetarian diet and lack of sunlight exposures.