Muhammed Kaya

Background: Although it has been suggested that papillary morphology and periampullary diverticulum (PAD) may affect the outcomes of endoscopic retrograde cholangiopancreatography (ERCP), the independent effects of these factors have not been clearly established. In this study, we aimed to evaluate the association of papillary morphology and PAD with ERCP success, procedural difficulty, and post-ERCP complications. Methods: Records of 1046 ERCP procedures performed at a single center were retrospectively reviewed. The primary analysis included 693 patients with native papillae and no prior sphincterotomy. Papilla morphology was available for 381 patients and periampullary diverticulum (PAD) status for 633. Outcomes included cannulation success, difficult cannulation, cannulation time, number of cannulation attempts, post-ERCP complications, and length of hospital stay. Multivariable Firth penalized logistic regression was used to evaluate independent associations with difficult cannulation, overall complications, cannulation failure, and post-ERCP pancreatitis (PEP), adjusting for papilla morphology, PAD status, age, sex, American Society of Anesthesiologists (ASA) physical status class, and Charlson Comorbidity Index (CCI). Results: Regular papilla morphology, compared with the pooled group of atypical papilla morphologies (Small, Bulging, Ridged), was associated with significantly higher cannulation success (97.4% vs. 91.2%; p = 0.012), shorter cannulation time (median 3.0 vs. 4.0 min; p = 0.009), fewer cannulation attempts (p = 0.007), and shorter hospital stay (median 5.0 vs. 6.0 days; p = 0.013). The presence of a PAD was not significantly associated with any procedural outcome or complication (all p > 0.05). CCI was independently associated with cannulation failure (adjusted OR 1.40 per one-point increase; 95% CI 1.03–1.91; p = 0.031) and was the only factor reaching statistical significance across the four multivariable models. The multivariable model showed modest discrimination for difficult cannulation (area under the receiver operating characteristic curve [AUC] = 0.596; 95% CI 0.515–0.675). Conclusions: Atypical papillary morphology was associated with lower cannulation success, longer cannulation time, and more cannulation attempts in univariable analyses; however, neither papillary morphology nor periampullary diverticulum was independently associated with ERCP outcomes. Among the variables evaluated, higher CCI was the only factor independently associated with cannulation failure; however, this finding should be interpreted cautiously given the small number of failure events.

Objective: In ulcerative colitis (UC), endoscopic assessment remains central to disease monitoring, but repeated colonoscopy is invasive and resource-intensive. This study evaluated the association and discriminatory performance of the systemic immune–inflammation index (SII; platelet × neutrophil/lymphocyte) and the hemoglobin–albumin–lymphocyte–platelet (HALP; hemoglobin × albumin × lymphocyte/platelet) score for endoscopic activity in UC and explored whether azathioprine use modified these associations. Methods: Among 428 retrospectively reviewed patients with UC, 218 met the inclusion criteria. Mayo-defined activity (endoscopic score ≥ 2) and Rachmilewitz EAI-defined activity (score ≥ 4) were analyzed as separate outcomes. Laboratory parameters were compared between active disease and remission groups. Receiver operating characteristic (ROC) analyses, multivariable logistic regression, sensitivity analyses accounting for disease duration and treatment category, and azathioprine interaction analyses were performed. Results: According to the Mayo and Rachmilewitz EAI definitions, 80 (36.7%) and 150 (68.8%) patients, respectively, had active disease. For Mayo-defined activity, CRP showed the highest discrimination (AUC = 0.720), followed by SII (AUC = 0.692), whereas HALP showed limited discrimination (AUC = 0.598). In the primary multivariable Mayo model, CRP, SII, younger age, and male sex were independently associated with activity, whereas HALP and azathioprine use were not. Adding SII to CRP produced only a small numerical increase in AUC (0.720 to 0.752), and adding HALP produced essentially no further change. No significant interaction between azathioprine use and SII or HALP was identified. Conclusion: SII was associated with endoscopic activity but showed only modest discriminatory performance, while HALP had limited discriminatory and independent predictive value. CRP remained the strongest individual biomarker. SII and HALP should therefore be interpreted as adjunctive inflammatory indices rather than substitutes for established biomarkers or endoscopic assessment.

Background/Aims: Patients with prior exposure to hepatitis B virus (HBV) (HBsAg [Hepatitis B surface antigen]-negative/anti-HBc [Hepatitis B core] immunoglobulin G (IgG)-positive) who receive immunosuppressive therapy (IST) remain susceptible to HBV reactivation (HBVr). Current clinical guidelines generally estimate HBVr risk according to the immunosuppressive potential of individual agents. However, evidence regarding the cumulative risk associated with the concurrent use of multiple agents within the same risk category remains limited. The current study investigated the effect of frequently used moderate risk IST combinations on the development of HBVr. Materials and Methods: A total of 406 HBsAg-negative/anti-HBc IgG-positive patients treated with moderate-risk IST were retrospectively analyzed. Patients were classified according to the treatment regimen into monotherapy (n = 178) and combination therapy (n = 228). HBVr was defined as either HBsAg seroconversion or the detection of HBV DNA during follow-up. The incidence of HBVr was compared between groups. Results: No significant differences were observed between the groups in baseline demographic and clinical features, including age, sex, and IST-related risk profiles. Among patients receiving combination therapy (58.7% female; mean age 62.8 ± 10.2 years), HBVr occurred in 6 patients, including 4 cases with HBV flare, whereas no reactivation occurred in the monotherapy group (62.3% female; mean age 63.6 ± 10.1 years). All patients who developed HBVr were anti-HBs-negative at baseline. HBVr occurred significantly more frequently among patients receiving combination therapy (P < .05). Conclusion: The use of combination IST and baseline anti-HBs negativity were identified as 2 important factors associated with increased risk of HBVr in HBsAg-negative/anti-HBc IgG-positive patients. In this subgroup, a clinical approach favoring antiviral prophylaxis may be considered. Further prospective studies with larger sample sizes are needed to fully elucidate this association. Cite this article as: Sadeçolak M, Düzenli T, Durak İ, et al. Increased risk of hepatitis B virus reactivation in patients with resolved hepatitis B virus infection receiving combination immunosuppressive therapy: The role of anti-HBs status. Turk J Gastroenterol. Published online June 2, 2026. doi: 10.5152/tjg.2026.26167.

Aim: Adequate bowel preparation is essential for high-quality colonoscopy and directly affects key quality indicators such as adenoma detection and cecal intubation. Although low-volume, nonpolyethylene glycol (PEG) regimens are widely used in clinical practice, real-world comparative data between stimulant-based preparations and sodium picosulfate-based combinations remain limited. This study aimed to compare the effectiveness and tolerability of sennoside A + B versus sodium picosulfate/magnesium oxide/citric acid (PM/Ca) using the Boston Bowel Preparation Scale (BBPS). Methods: This prospective, randomized, observer-blinded trial included adults aged 18–80 years undergoing elective outpatient colonoscopy. Participants were randomized 1:1 to receive either sennoside A + B oral solution (split-dose: 250 mL at 21:00 and 250 mL at 23:00) or PM/Ca (two sachets at 19:00 and 21:00), both administered with a low-residue diet and written instructions; rectal enemas were applied as part of the institutional protocol. Bowel cleanliness was assessed using BBPS. Adequate preparation was defined as BBPS > 6. Multivariable logistic regression was performed to identify independent predictors of adequate preparation. Results: A total of 705 patients were included in the primary analysis cohort (341 sennoside A + B; 364 PM/Ca). Adequate bowel preparation (BBPS > 6) was achieved more frequently in the sennoside A + B group than in the PM/Ca group (70.1% versus 56.3; p < 0.001), and the mean BBPS score was higher (6.64 ± 1.78 versus 5.93 ± 1.92; p < 0.001). Polyp detection rates were similar between groups (21.4% versus 26.6; p = 0.138). In multivariable analysis, higher education (OR 1.38; 95% CI 1.06–1.81; p = 0.016) and sennoside A + B (OR 1.77; 95% CI 1.29–2.43; p < 0.001) were independent predictors of adequate preparation, whereas age, BMI, sex, diabetes mellitus, and constipation were not. Preparation intolerance was more frequent in the sennoside A + B group (7.0% versus 0.7%; p < 0.001; tolerance analysis n = 824). Failure to reach the cecum did not differ significantly between regimens (9.3% versus 12.3%; p = 0.216; analyzed in the entire study population n = 791). Conclusions: In routine clinical practice, sennoside A + B provided higher cleansing efficacy than PM/Ca as reflected by higher BBPS scores and a greater probability of achieving adequate bowel preparation. However, PM/Ca demonstrated a more favorable tolerability profile. Bowel preparation selection should balance efficacy and tolerability while considering patient-related factors such as educational level. Trial registration: ClinicalTrials.gov, NCT06580366.

Background/Aim: Melatonin is a cytoprotective hormone with antioxidant activity and also mediates regulatory effects that inhibit tumor proliferation and angiogenesis. This study aimed to evaluate serum melatonin levels and sleep quality in patients with newly diagnosed colorectal cancer (CRC) compared with controls and to investigate whether melatonin could serve as a potential biomarker. Materials and Methods: A total of 71 participants (36 CRC, 35 controls) were included. Blood samples were obtained between 01:00- 02:00 am and serum melatonin was measured using a high-sensitivity (ELISA) Enzyme-Linked Immunosorbent Assay kit. Sleep quality was assessed with the Pittsburgh Sleep Quality Index (PSQI) and sleep apnea risk was determined by the STOP-Bang questionnaire. Group comparisons were performed, followed by multivariable logistic regression and receiver-operating characteristic analysis. Results: Colorectal cancer patients had significantly lower nocturnal serum melatonin concentrations (131.1 Å} 35.5 vs. 194.8 Å} 50.8 pg/ mL, P < .001) and higher PSQI scores (5.6 Å} 3.1 vs. 5.1 Å} 3.0, P = .028). In multivariable analysis, melatonin remained the only independent predictor of CRC (OR = 0.952, 95% CI: 0.929-0.976, P < .001). Receiver-operating characteristic analysis identified a melatonin threshold of ~150 pg/mL, discriminating CRC patients from controls with 75% sensitivity and 91.4% specificity (AUC = 0.877). Conclusion: Although cancer patients and the control group showed comparable obstructive sleep apnea risk, sleep quality was poorer, and melatonin levels were significantly lower in the cancer group. Melatonin assessment can complement traditional risk stratification and may provide new insights into the interplay between circadian biology, sleep, and colorectal carcinogenesis. Cite this article as: Durak I, Durak B, Duzenli T, et al. Nocturnal melatonin deficiency in colorectal cancer: independent predictive value beyond sleep quality. Turk J Gastroenterol. Published online February 23, 2026. doi: 10.5152/tjg.2026.25808.

Çölyak hastalığı (Gluten Enteropatisi), genetik olarak yatkın bireylerde gluten tüketiminin tetiklediği kronik, immün aracılı bir durumdur. Genel popülasyonun yaklaşık %1'i bu hastalıktan etkilenmektedir. Hastalığın ortaya çıkış mekanizmaları heterojendir (genetik faktörler, çevresel faktörler, glutene maruziyet vs.) ve hekimler ile halk arasında farkındalığın artmasına rağmen, hala tanısal oranlar gerçek hastalık oranlarına göre düşük gibi görünmektedir. Hastalığın genel belirtileri arasında ishal, karın ağrısı, şişkinlik, anemi, vitamin eksiklikleri, büyüme ve gelişme geriliği, adet düzensizlikleri gibi çeşitli bulgular yer almaktadır. Teşhis edilmemiş çölyak hastalığını tanımlamanın en etkili stratejisi, yüksek riskli gruplarda serolojik testler yoluyla vakaları tespit etmektir. Ömür boyu glutensiz diyet, çölyak hastalığı ve diğer glutenle ilişkili bozuklukların tek tedavisidir. Bu bozuklukta glutensiz diyeti takiben ortaya çıkan klinik düzelme, serolojik testlerdeki düzelme ve mukozal iyileşme dramatiktir. Bununla birlikte, glutensiz gıdaya sıkı sıkıya bağlı kalmak; sosyal izolasyon, gluten kontaminasyonu riski, yüksek maliyet, düşük kalite ve glutensiz ürünlerin tadıyla ilgili endişeler nedeniyle çoğu zaman zor olmaktadır.

Background and Aims: Turkish Journal of Gastroenterology is recognized as a prestigious international journal and stands as one of the leading publications in the field of gastroenterology, where researchers closely follow current articles. This research aims to provide a comprehensive perspective on the characteristics of publications in this journal from 2007 to 2023, utilizing bibliometric techniques. Materials and Methods: Articles from Turkish Journal of Gastroenterology, published between 2007 and 2023, were retrieved from the Web of Science database. Subsequent performance analyses were conducted on the same database, and network visualization maps were generated using the VOSviewer package program (Version 1.6.17, Leiden University's Center for Science and Technology Studies). Results: This research includes a total of 1537 articles, with the top three contributing countries being Türkiye, China, and South Korea, respectively. The most frequently addressed topics in publications are ‘Ulcerative colitis’ and ‘Helicobacter pylori’. The reference lists of the 1537 articles collectively contain 35 406 citations and the articles received 9800 citations. The most cited institutions are Ankara University, Ege University, Istanbul University, Gazi University, and Hacettepe University. The most commonly used keywords are "Helicobacter pylori", "Ulcerative colitis", "Children", "Crohn's disease" and "Inflammatory bowel disease". Conclusion: By offering a holistic perspective on the features of articles published in the Turkish Journal of Gastroenterology, this research has the potential to make a meaningful contribution to the literature and establish a noteworthy impact on research within the field of gastroenterology.

The role of human microbiota in mental health and the underlying mechanisms of psychobiotics, which can modulate mood and behavior through the microbiota–gut–brain axis, has been a focus of scientific scrutiny. This work presents a bibliometric analysis to uncover research trends and insights in psychobiotics literature. The Clarivate Analytics Web of Science database served as the source for articles and reviews on psychobiotics spanning the years 2012 to 2023. Bibliometric network visualization and graphing were conducted using VOSviewer, Microsoft Excel for Windows 10, and Datawrapper software. A total of 348 publications were included, and it has been determined that the number of publications and citations shows an increasing trend from 2012 to 2023. The most active authors on psychobiotics, in order, were Dinan TG, Cryan JF, and Tsai YC. The most active organizations have been identified as University College Cork, National Yang Ming Chiao Tung University, and Bened Biomedical Co. Ltd. The most active countries in psychobiotic research were China, Ireland, and United States of America, while the most active journals were Nutrients, International Journal of Molecular Sciences, and Probiotics and Antimicrobial Proteins. The most commonly used keywords were “psychobiotics,” “probiotics,” and “gut–brain axis.” This bibliometric analysis has revealed the growing academic interest in psychobiotics, indicating that the relationship between gut microbiota and mental health will increasingly be supported by scientific evidence in the years ahead.