Background/Aims: We investigated whether patients with inflammatory bowel disease (IBD) in Korea have an increased risk of hepatitis A virus (HAV) and hepatitis C virus (HCV) infections and sought to identify the risk factors for these infections. Methods: We performed a nationwide population-based study using 2013–2021 data from the Korean National Health Insurance Claims Database. We calculated the incidence rates and standardized incidence ratios (SIRs) of HAV and HCV infections in patients with IBD compared with the overall Korean population. Results: A total of 43,513 patients were included in this study. A total of 317 cases of HAV were identified in 276,007 perdison- years, while 297 cases of HAV developed in the Korean general population. The SIR of HAV in the patients with IBD was 1.07 (95% confidence interval [CI], 0.96–1.19) and the increase of HAV infection in patients with IBD was not statistically significant. A total of 289 cases of HCV infection were identified in 276,538 person-years, while 242 cases of HCV infection developed in the Korean general population. The SIR of HCV in patients with IBD was 1.19 (95% CI, 1.06–1.34) and the increase of HCV infection in patients with Crohn's disease (SIR, 1.63; 95% CI, 1.31–2.04). Corticosteroid use was identified as a risk factor for HAV and HCV infections in patients with IBD. Conclusions HCV showed an increasing trend in Korean patients with IBD, especially those with Crohn's disease. Corticosteroids use is a risk factor for hepatitis in patients with IBD.

Objective: We investigated the distribution of AI viruses in fecal samples from wild bird habitats (and nearby poultry-farm areas) surveyed between September and March from 2019 to 2025 and identified associated epidemiological risk factors. Methods: Samples were screened for influenza A (M, H5, H7) genes using real-time reverse transcription polymerase chain reaction (PCR), subjected to virus isolation in embryonated chicken eggs, and subtyped by PCR and sequencing. Host species were identified through DNA barcoding. Relative risks (RRs) with 95% confidence intervals were estimated for province, month, and waterfowl density. Results: Overall prevalence of HPAI and low pathogenic AI (LPAI) virus was 0.10% and 3.21%, respectively. HPAI virus was continuously isolated since 2020–2021, except 2019– 2020, while LPAI prevalence steadily increased (3.01%–4.35%). Twelve hemagglutinin (H1–H12) subtypes were identified in 1,722 isolates, and H3 (16.5%) was the most prevalent, followed by H5 (11.1%) and H7 (5.2%). LPAI H5N3 (55.7%) and H7N7 (75.5%) were the predominant H5 and H7 subtypes, respectively. Detection was higher in western coastal provinces, and higher mallard/spot-billed duck density and sampling in September– December were associated with increased risk. Conclusions and Relevance: Continued surveillance of migratory-bird habitats can provide early warning of HPAIV incursions and support targeted biosecurity measures in high-risk regions and seasons.

The H9N2 avian influenza (AI) has become endemic in poultry in many countries since the 1990s, which has caused considerable economic losses in the poultry industry. Considering the long history of the low pathogenicity H9N2 AI in many countries, once H9N2 AI is introduced, it is more difficult to eradicate than high pathogenicity AI. Various preventive measures and strategies, including vaccination and active national surveillance, have been used to control the Y439 lineage of H9N2 AI in South Korea, but it took a long time for the H9N2 virus to disappear from the fields. By contrast, the novel Y280 lineage of H9N2 AI was introduced in June 2020 and has spread nationwide. This study reviews the history, genetic and pathogenic characteristics, and control strategies for Korean H9N2 AI. This review may provide some clues for establishing control strategies for endemic AIV and a newly introduced Y280 lineage of H9N2 AI in South Korea.

Background/Aims: Efficacy of proton pump inhibitors is limited in patients with nonerosive reflux disease (NERD). The aim of this study was to comparatively evaluate the efficacy and safety of esomeprazole with sodium bicarbonate and esomeprazole alone. Methods: This was a multicenter, randomized, double-blind, active-controlled, noninferiority comparative study. A total of 379 patients with NERD were randomly allocated to receive either EsoduoⓇ/sup> (esomeprazole 20 mg with sodium bicarbonate 800 mg) or NexiumⓇ/sup> (esomeprazole 20 mg) once daily for 4 weeks from January 2019 to December 2019. The patients had a history of heartburn for at least 2 days in the week before randomization as well as in the last 3 months and no esophageal mucosal breaks on endoscopy. The primary endpoint was a complete cure of heartburn at week 4. The secondary and exploratory endpoints as well as the safety profiles were compared in the groups at weeks 2 and 4. Results: A total of 355 patients completed the study (180 in the EsoduoⓇ/sup> group and 175 in the NexiumⓇ/sup> group). The proportions of patients without heartburn in the entire 4th week of treatment were not different between the two groups (33.33% in the EsoduoⓇ/sup> group and 35% in the NexiumⓇ/sup> group, p=0.737). There were no significant differences in most of the secondary and exploratory endpoints as well as the safety profiles. Conclusions EsoduoⓇ/sup> is as effective and safe as NexiumⓇ/sup> for managing typical symptoms in patients with NERD (ClinicalTrial.gov identifier: NCT03928470).

Background/Aims: Subepithelial tumors (SETs) are small, mostly asymptomatic lesions with normal overlying mucosa, usually identified incidentally on endoscopy. The aim of this study was to evaluate the pathologic diagnosis of SETs, and to assess the diagnostic yield and impact of endoscopic submucosal dissection (ESD) biopsy on the management of patients with SETs. Materials and Methods: We included 52 subepithelial lesions in this study during the study period. Inclusion criteria included size of the SET >2 cm, and a gastrointestinal stromal tumor (GIST) that cannot be excluded using EUS. We performed an endoscopic biopsy of each SET using the ESD technique. Results: The mean diameter of the lesions was 24.15±6.0 mm. The diagnostic yield of this method was 96.15%. Among the 52 participants, 45 were located in the stomach, four in the esophagus, and three in the duodenum. The pathologic diagnoses included: 17 leiomyomas, 13 GISTs, 11 ectopic pancreases, two carcinomas, two inflammatory fibroid polyps, two Brunner’s gland hyperplasia, two lipomas, one glomus tumor, and two remained undiagnosed. The mean duration of the procedure was 13.44±2.41 minutes. Three complications were associated with the procedure. Conclusions Deep biopsy via ESD is useful in determining the histopathologic nature of SETs. This method minimizes the need for unnecessary surgery in benign SETs.

Purpose: In young patients with varicocele, preservation of the internal spermatic artery may be advantageous for catch-up growth, but it may also increase the likelihood of treatment failure. Intraoperative venography reduces the likelihood that unsealed veins will remain after varicocelectomy. We analyzed the characteristics of remnant veins visualized through intraoperative venography to investigate the cause of surgical failure in artery-sparing varicocelectomy (ASV). Materials and Methods: We retrospectively analyzed clinical characteristics and outcomes of patients aged 18 years or younger who underwent varicocelectomy with intraoperative venography from January 2005 to December 2017. During varicocelectomy, intraoperative venography was performed to distinguish veins from other structures. Any unsealed veins that were discovered were ligated and classified using the Bähren system. Results: One hundred and sixty-two patients underwent intraoperative venography: 153 cases (94.4%) were for primary varicocelectomy, and 9 cases (5.6%) were for repeat varicocelectomy. Open varicocelectomy was performed in 105 cases (64.8%), and laparoscopic varicocelectomy was performed in 57 cases (35.2%). Venography revealed remnant veins after the first ligation in 51 cases (31.2%), 46 (90.2%) and 5 (9.8%) of which were Bähren types 3 and 4, respectively. Five patients (3.1%) experienced varicocele recurrence, classified as persistence in 1 patient (0.6%) and relapse in 4 patients (2.5%). Conclusion Remnant collateral veins of the internal spermatic vein (ISV) (Bähren type 3) are the most common cause of failure in ASV. In a few patients, an external spermatic vein merges with the ISV at a higher level (Bähren type 4) and is unidentifiable without venography.

Background/Aims: To date, studies on various noninvasive techniques have been suggested to evaluate the degree of liver fibrosis. We aimed to investigate the diagnostic performance of se-rum asialo α1-acid glycoprotein (AsAGP) in the diagnosis of liver cirrhosis compared with chronic hepatitis for clinically useful result. Methods: We conducted a case-control study of 96 patients with chronic liver disease. Chronic hepatitis was defined as the presence of chronic liver disease on ultrasonography, with a liver stiffness of less than 5.0 kPa as shown on magnetic resonance elastography (MRE). Liver cirrho-sis was defined as liver stiffness of more than 5.0 kPa on MRE. The serum AsAGP concentration was compared between the two groups. Results: Serum AsAGP levels were significantly higher in patients with cirrhosis than in those with chronic hepatitis (1.83 μg/mL vs 1.42 μg/mL, p<0.001). Additionally, when comparing pa-tients in each cirrhotic group (Child-Pugh grades A, B, and C) to those with chronic hepatitis, AsAGP levels were significantly higher in all the cirrhotic groups (p<0.05, p<0.01, p<0.001, respectively). The sensitivity and specificity of AsAGP for detecting cirrhosis were 79.2% and 64.6%, respectively, and the area under the curve value was 0.733. The best diagnostic cutoff to predict cirrhosis was 1.4 μg/mL. AsAGP and bilirubin were found to be independent risk factors for the prediction of cirrhosis in the logistic regression analysis. Conclusions Serum AsAGP showed an acceptable diagnostic performance in predicting liver cirrhosis.

Background/Aims: Prokinetics such as mosapride citrate CR (conventional-release; Gasmotin) are commonly used in functional dyspepsia (FD). This study aims to evaluate the efficacy and safety of once-a-day mosapride citrate SR (DWJ1252), a sustained-release formulation of mosapride citrate, compared with mosapride citrate CR 3 times a day, in patients with FD. Methods: In this multicenter, randomized, double-blind, active-controlled, non-inferiority study, 119 patients with FD (by the Rome III criteria, 60 for mosapride citrate SR and 59 for mosapride citrate CR) were randomly allocated to mosapride citrate SR once daily or mosapride citrate CR thrice daily for 4 weeks in 16 medical institutions. Primary end point was the change in gastrointestinal symptom (GIS) score from baseline, assessed by GIS questionnaires on 5-point Likert scale after 4-week treatment. Secondary end points and safety profiles were also analyzed. Results: The study included 51 and 49 subjects in the mosapride citrate SR and mosapride citrate CR groups, respectively. GIS scores at week 4 were significantly reduced in both groups (mean ± SD: − 10.04 ± 4.45 and − 10.86 ± 5.53 in the mosapride citrate SR and mosapride citrate CR groups, respectively; P < 0.001), and the GIS changes from baseline did not differ between the 2 groups (difference, 0.82 point; 95% CI, − 1.17, 2.81; P = 0.643). Changes in GIS at weeks 2 and 4 and quality of life at week 4, and the improvement rates of global assessments at weeks 2 and 4, did not differ between the groups. Adverse events were similar in the 2 groups, and there were no serious adverse events. Conclusion In patients with FD, mosapride citrate SR once daily is as effective as mosapride citrate CR thrice daily, with a similar safety profile.