Jongha Park

Optimal preparation-to-colonoscopy interval in split-dose PEG bowel preparation determines satisfactory bowel preparation quality: an observational prospective study.

BACKGROUND Several factors influence bowel preparation quality. Recent studies have indicated that the time interval between bowel preparation and the start of colonoscopy is also important in determining bowel preparation quality. OBJECTIVE To evaluate the influence of the preparation-to-colonoscopy (PC) interval (the interval of time between the last polyethylene glycol dose ingestion and the start of the colonoscopy) on bowel preparation quality in the split-dose method for colonoscopy. DESIGN Prospective observational study. SETTING University medical center. PATIENTS A total of 366 consecutive outpatients undergoing colonoscopy. INTERVENTION Split-dose bowel preparation and colonoscopy. MAIN OUTCOME MEASUREMENTS The quality of bowel preparation was assessed by using the Ottawa Bowel Preparation Scale according to the PC interval, and other factors that might influence bowel preparation quality were analyzed. RESULTS Colonoscopies with a PC interval of 3 to 5 hours had the best bowel preparation quality score in the whole, right, mid, and rectosigmoid colon according to the Ottawa Bowel Preparation Scale. In multivariate analysis, the PC interval (odds ratio [OR] 1.85; 95% CI, 1.18-2.86), the amount of PEG ingested (OR 4.34; 95% CI, 1.08-16.66), and compliance with diet instructions (OR 2.22l 95% CI, 1.33-3.70) were significant contributors to satisfactory bowel preparation. LIMITATIONS Nonrandomized controlled, single-center trial. CONCLUSIONS The optimal time interval between the last dose of the agent and the start of colonoscopy is one of the important factors to determine satisfactory bowel preparation quality in split-dose polyethylene glycol bowel preparation.

Is endoscopic resection an acceptable treatment for undifferentiated EGC

BACKGROUND/AIMS Endoscopic resection (ER) is an effective treatment in selected patients with early gastric cancer (EGC). We have evaluated the clinical outcomes of ER in patients with undifferentiated EGCs, including poorly differentiated adenocarcinoma or signet ring cell carcinoma. METHODOLOGY We retrospectively examined the medical records of 77 patients diagnosed with undifferentiated EGC after ER (EMR for 22 patients and ESD for 56 patients) at a single center. RESULTS The mean±SD lesion size was 23.2±14.1mm. The 77 lesions included 65 (84.4%) intramucosal cancers and 12 (15.6%) involving the submucosal layer. Of these 77 patients, 35 underwent curative resection and 42 did not. After a mean follow-up period of 41 months (range, 9-152), local recurrences were observed in four patients (5.2%), all of whom had not undergone curative resection. No patient died of EGC. Univariate analysis showed that tumor involvement of the resection margins (p<0.001) and lymphatic invasion (p=0.003) were significant risk factors for recurrence after ER in undifferentiated EGCs. However, multivariate analysis did not show any significant risk factors. CONCLUSIONS ER may be an alternative treatment modality for selected patients with undifferentiated EGCs.

The Effectiveness of Short Message Service to Assure the Preparation-to-Colonoscopy Interval before Bowel Preparation for Colonoscopy

Background/Aims. The preparation-to-colonoscopy (PC) interval is one of several important factors for the bowel preparation. Short message service (SMS) reminder from a cellular phone has been suggested to improve compliance in various medical situations. We evaluated the effectiveness of SMS reminders to assure the PC interval for colonoscopy. Methodology. This prospective randomized study was investigator blinded. In the No-SMS group, patients took the first 2 L polyethylene glycol (PEG) between 6 and 8 PM on the day before colonoscopy and the second 2 L PEG approximately 6 hours before the colonoscopy without SMS. In the SMS group, patients took first 2 L PEG in the same manner as the No-SMS group and the second 2 L PEG after receiving an SMS 6 hours before the colonoscopy. Results. The SMS group had a lower score than the No-SMS group, according to the Ottawa Bowel Preparation Scale (P < 0.001). Multivariate logistic regression analysis showed that compliance with diet instructions (odds ratio (OR) 2.109; 95% confidence interval (CI), 1.11–3.99, P = 0.022) and intervention using SMS ((OR) 2.329; 95% (CI), 1.34–4.02, P = 0.002) were the independent significant factors for satisfactory bowel preparation. Conclusions. An SMS reminder to assure PC interval improved the bowel preparation quality for colonoscopy with bowel preparation.

DNA hypermethylation of a selective gene panel as a risk marker for colon cancer in patients with ulcerative colitis

Patients with inflammatory bowel disease (IBD) which includes ulcerative colitis (UC) and Crohns disease (CD) of the colon are at risk of developing colorectal cancer (CRC). Here, we analyzed the methylation status of selected genes as a risk marker in UC patients. We assessed methylation frequency of 4 genes [secreted frizzled-related protein 1 (SFRP1), transcription elongation regulator 1-like (TCERG1L), fibrillin 2 (FBN2) and tissue factor pathway inhibitor 2 (TFPI2)] in biopsies of 36 UC patients. SFRP1 and TCERG1L genes showed high methylation frequencies but FBN2 and TFPI2 genes showed methylation frequencies of 50% in UC patients which suggests that our sensitive selective markers could detect half of the UC patients. We also confirmed the methylation status in UC tissues by bisulfite sequencing analysis. We compared the levels of methylation in terms of quantification between UC patients and CRC tumors. Importantly, methylation levels of these 4 genes were found to be significantly higher in CRC compared to UC patients, even though we noted a frequent methylation pattern in UC patients. Our data suggest that sensitive DNA methylation markers are able to identify UC patients and this would implicate the risk of CRC. Therefore, assessing the methylation of these 4 genes in UC patients could contribute to prevent the progression of severe disease with regular colonoscopic surveillance.

Low-Volume Morning-Only Polyethylene Glycol with Specially Designed Test Meals versus Standard-Volume Split-Dose Polyethylene Glycol with Standard Diet for Colonoscopy: A Prospective, Randomized Trial

Background/Aims: Split-dose polyethylene glycol (PEG) is a standard bowel preparation regimen for colonoscopy, but the large volume is burdensome to ingest and the night dose causes sleep disturbance. This study was performed to evaluate the efficacy and tolerability of a bowel preparation protocol using low-volume morning-only PEG with specially designed low-residue test meals (LV-PEG with TM) compared to a standard-volume split-dose PEG bowel preparation with a standard diet (SV-PEG with SD). Methods: This was a single-center, prospective, randomized, investigator-blinded, noninferiority study. The primary end point was bowel preparation quality according to the Ottawa scale. Tolerability, compliance, adverse events, sleep quality and polyp/adenoma detection were also assessed. Results: Among 197 patients analyzed (mean age 54.6 years, 51.3% men), 97 received LV-PEG with TM and 100 received SV-PEG with SD. The Ottawa score for the total colon was 3.76 ± 2.07 in the LV-PEG with TM group and 3.67 ± 1.57 in the SV-PEG with SD group (p = 0.723; difference 0.09, 95% confidence interval -0.60 to 0.42). The compliance was high (more than 95%) in both groups (p = 0.621). PEG was easier to ingest for patients in the LV-PEG with TM group compared to the SV-PEG with SD group [visual analogue scale (VAS) for difficulty: 4.64 ± 2.46 vs. 5.97 ± 2.42, respectively; p < 0.001]. Diet instructions were also easier to comply with for patients in the LV-PEG with TM group compared to the SV-PEG with SD group (VAS for difficulty: 3.11 ± 2.25 vs. 4.00 ± 2.39, respectively; p = 0.008). Patients in the LV-PEG with TM group had a lower incidence of abdominal bloating (p = 0.012) and better sleep quality (p < 0.001). There was no difference between the groups regarding polyp and adenoma detection. Conclusions: LV-PEG with TM and SV-PEG with SD have similar efficacy with regard to bowel preparation for colonoscopy. LV-PEG with TM provided easier PEG intake and diet compliance, less abdominal bloating and better sleep quality than SV-PEG with SD.

The efficacy and safety of carbon dioxide insufflation during colonoscopy with consecutive esophagogastroduodenoscopy in moderately sedated outpatients: a randomized, double-blind, controlled trial.

Goals and Background: Colonoscopy with consecutive esophagogastroduodenoscopy (CCEGD) can be more convenient than performing each procedure individually. There has been no randomized controlled trial comparing carbon dioxide (CO2) versus air insufflations during CCEGD in sedated patients. CO2 insufflation instead of air during CCEGD may reduce abdominal pain and be more comfortable. We investigated the efficacy and safety of CO2 insufflation during CCEGD in moderately sedated outpatients. Study: This was a randomized, double-blind, controlled trial. A total of 96 outpatients were randomly assigned to the groups of CO2 or air insufflation. Postprocedure pain was assessed using a 0 to 10 visual analogue scale, and the proportion of pain-free patients was compared between the groups. Waist circumferences and end-tidal CO2 (ETCO2) were measured. Results: Among 96 patients, cecal intubation failed in 2 patients, who were excluded from the analysis. Forty-eight patients in the CO2 and 46 patients in the air group completed the study. There was significant difference between the 2 groups regarding the proportion of pain-free patients 30 minutes after the procedures [air group, 35/46 (76.1%) vs. CO2 group, 44/48 (91.6%)] (P=0.03). However, there was no significant difference in the proportion at 6 and 24 hours after the procedures. The mean increase in waist circumference was greater with air than with CO2 (1.54 vs. 0.18 cm, P<0.001). The ETCO2 measured immediately after the procedures was slightly higher in the CO2 group than in the air group (38.6 vs. 37.2 mm Hg, P=0.02), but the values were within the normal range. No significant adverse events occurred. Conclusions: CO2 insufflation during CCEGD reduced postprocedural pain and distension compared with air. It was comfortable and safe to use in moderately sedated outpatients.

Determination of the optimal time for premedication with pronase, dimethylpolysiloxane, and sodium bicarbonate for upper gastrointestinal endoscopy.

Goals and Background: Premedication with pronase, dimethylpolysiloxane, and sodium bicarbonate improves visibility during upper gastrointestinal (UGI) endoscopy. However, the optimal time for this combination to take effect is unknown. We investigated the optimal time of pre-UGI endoscopy medication. Study: A randomized, investigator-blind, controlled trial. The 300 patients who were to receive premedication were randomized into 3 groups according to the following medication time before UGI endoscopy: 10 minutes (group A, n=98), 10 to 30 minutes (group B, n=97), and 30 minutes premedication (group C, n=99). Visibility scores (range, 1 to 4, with lower scores indicating better gastric mucosal visibility) were assessed for the antrum, lower body, upper body, and fundus and compared, including the sum of the scores, between the 3 groups. Results: Group B had significantly lower visibility scores for the lower body, upper body, and fundus than group C (P=0.001, 0.009, and 0.002, respectively). Group A obtained significantly lower scores for the antrum and lower body than group C (P=0.007 and 0.005, respectively). The total visibility scores of groups A and B were significantly lower compared with those of group C (P=0.001, 0.003, respectively). Conclusions: Administration of pronase, dimethylpolysiloxane, and sodium bicarbonate within 30 minutes before UGI endoscopy significantly improved endoscopic visualization. However, the optimal time to achieve the best visibility was between 10 to 30 minutes before UGI endoscopy.

Efficacy of prokinetics with a split-dose of polyethylene glycol in bowel preparation for morning colonoscopy: a randomized controlled trial.

Background/Aims: Currently, a split-dose of polyethylene glycol (PEG) is the mainstay of bowel preparation due to its tolerability, bowel-cleansing action, and safety. However, bowel preparation with PEG is suboptimal because residual fluid reduces the polyp detection rate and requires a more thorough colon inspection. The aim of our study was to demonstrate the efficacy of a sufficient dose of prokinetics on bowel cleansing together with split-dose PEG. Methods: A prospective endoscopist-blinded study was conducted. Patients were randomly allocated to two groups: prokinetic with split-dose PEG or split-dose PEG alone. A prokinetic [100 mg itopride (Itomed®)], was administered twice simultaneously with each split-dose of PEG. Bowel-cleansing efficacy was measured by endoscopists using the Ottawa scale and the segmental fluidity scale score. Each participant completed a bowel preparation survey. Mean scores from the Ottawa scale, segmental fluid scale, and rate of poor preparation were compared between both groups. Results: Patients in the prokinetics with split-dose PEG group showed significantly lower total Ottawa and segmental fluid scores compared with patients in the split-dose of PEG alone group. Conclusion: A sufficient dose of prokinetics with a split-dose of PEG showed efficacy in bowel cleansing for morning colonoscopy, largely due to the reduction in colonic fluid.

Does Polyethylene Glycol (PEG) Plus Ascorbic Acid Induce More Mucosal Injuries than Split-Dose 4-L PEG during Bowel Preparation?

Background/Aims The aims of this study were to compare the bowel-cleansing efficacy, patient affinity for the preparation solution, and mucosal injury between a split dose of poly-ethylene glycol (SD-PEG) and low-volume PEG plus ascorbic acid (LV-PEG+Asc) in outpatient scheduled colonoscopies. Methods Of the 319 patients, 160 were enrolled for SD-PEG, and 159 for LV-PEG+Asc. The bowel-cleansing efficacy was rated according to the Ottawa bowel preparation scale. Patient affinity for the preparation solution was assessed using a questionnaire. All mucosal injuries observed during colonoscopy were biopsied and histopathologically reviewed. Results There was no significant difference in bowel cleansing between the groups. The LV-PEG+Asc group reported better patient acceptance and preference. There were no significant differences in the incidence or characteristics of the mucosal injuries between the two groups. Conclusions Compared with SD-PEG, LV-PEG+Asc exhibited equivalent bowel-cleansing efficacy and resulted in improved patient acceptance and preference. There was no significant difference in mucosal injury between SD-PEG and LV-PEG+Asc. Thus, the LV-PEG+Asc preparation could be used more effectively and easily for routine colonoscopies without risking significant mucosal injury.

Detection of DNA hypermethylation in sera of patients with Crohn's disease

Mounting evidence suggests that inflammatory bowel disease (IBD) is caused by genetic predisposition of various genes as well as an abnormal interaction with environmental factors, resulting in epigenetic alterations. It has become evident that epigenetic factors play a significant contributory role during disease development. Additionally, DNA methylation has been reported to be correlated with the development of IBD. In the present study, we examined the role of DNA hypermethylation in Crohns disease (CD) patients. The transcription elongation regulator 1-like (TCERG1L) gene, which has been previously reported to be highly frequently methylated in colon tumors was selected as a candidate for the early detection of biomarkers for colon cancer patients. DNA methylation of TCERG1L in 101 serum samples of CD patients was examined. Results of conventional MSP analysis revealed high methylation [57% (58/101)] of serum samples in CD patients. The DNA methylation pattern of TCEEG1L was confirmed using bisulfate sequencing analysis. The results of the present study suggest that using regular colonoscopic surveillance sensitive DNA methylation markers may detect serum samples of CD patients, leading to reduced risk or prevention of the progression of advanced stages of disease.