Background: The World Health Organization has declared the end of the coronavirus disease 2019 (COVID-19) public health emergency. However, this did not indicate the end of COVID-19. Several months after the infection, numerous patients complain of respiratory or nonspecific symptoms; this condition is called long COVID. Even patients with mild COVID-19 can experience long COVID, thus the burden of long COVID remains considerable. Therefore, we conducted this study to comprehensively analyze the effects of long COVID using multi-faceted assessments. Materials and Methods: We conducted a prospective cohort study involving patients diagnosed with COVID-19 between February 2020 and September 2021 in six tertiary hospitals in Korea. Patients were followed up at 1, 3, 6, 12, 18, and 24 months after discharge. Long COVID was defined as the persistence of three or more COVID-19-related symptoms. The primary outcome of this study was the prevalence of long COVID after the period of COVID-19. Results: During the study period, 290 patients were enrolled. Among them, 54.5 and 34.6% experienced long COVID within 6 months and after more than 18 months, respectively. Several patients showed abnormal results when tested for post-traumatic stress disorder (17.4%) and anxiety (31.9%) after 18 months. In patients who underwent follow-up chest computed tomography 18 months after COVID-19, abnormal findings remained at 51.9%. Males (odds ratio [OR], 0.17; 95% confidence interval [CI], 0.05–0.53; P=0.004) and elderly (OR, 1.04; 95% CI, 1.00–1.09; P=0.04) showed a significant association with long COVID after 12–18 months in a multivariable logistic regression analysis. Conclusion Many patients still showed long COVID after 18 months post SARS-CoV-2 infection. When managing these patients, the assessment of multiple aspects is necessary.

Background/Aims: Patients with acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) typically have a poor prognosis; however, no effective treatment is available. In recent years, several retrospective studies have suggested the clinical benefits of direct hemoperfusion with a polymyxin B–immobilized fiber column (PMX-DHP) in patients with AE-IPF. Herein, we aimed to investigate the efficacy and safety of PMX-DHP treatment in patients with AE-IPF. Methods: Patients diagnosed with AE-IPF (n = 10) with a partial pressure of oxygen to fraction of inspiratory oxygen ratio (P/F ratio) > 100 were prospectively enrolled at a single center. PMX-DHP was performed twice for 6 hours (at 24-h intervals) at a flow rate of 80–100 mL/min, and steroid pulse therapy was concurrently administered (500 mg of methylprednisolone for 3 d). Results: The mean patient age was 67 years, and 80.0% were male. During the follow-up (median, 42.5 d; interquartile range, 16.0–174.0 d), seven (70.0%) patients died (including two who underwent transplantation); the in-hospital mortality rate was 70%, while the 30- and 90-day mortality rates were 50.0% and 70.0%, respectively. After 48 hours of PMX-DHP treatment, the P/F ratio improved (mean, 160.0 vs. 229.0; p = 0.054) and C-reactive protein level decreased (mean, 8.3 mg/dL vs. 3.5 mg/dL; p = 0.012). During hospitalization, no PMX-DHP–associated adverse events were observed. Conclusions Our results suggest that PMX-DHP treatment may be useful at improving oxygenation and reducing inflammation in patients with AE-IPF with acceptable safety profiles, however without affecting their prognosis.

Emerging evidence suggests that systemic inflammation may play a critical role in neurological disorders. Recent studies have shown the connection between inflammatory bowel diseases (IBD) and neurological disorders, revealing a bidirectional relationship through the gut-brain axis.Immunotherapies, such as Treg cells infusion, have been proposed for IBD. However, the role of adaptive immune cells in IBD-induced neuroinflammation remains unclear. In this study, we established an animal model for IBD in mice with severe combined immune-deficient (SCID), an adaptive immune deficiency, to investigate the role of adaptive immune cells in IBD-induced neuroinflammation. Mice were fed 1%, 3%, or 5% dextran sulfate sodium (DSS) for 5 days. We measured body weight, colon length, disease activity index (DAI), and crypt damage. Pro-inflammatory cytokines were measured in the colon, while microglial morphology, neuronal count, and inflammatory cytokines were analyzed in the brain. In the 3% DSS group, colitis symptoms appeared at day 7, with reduced colon length and increased crypt damage showing colitis-like symptoms. By day 21, colon length and crypt damage persisted, while DAI showed recovery. Although colonic inflammation peaked at day 7, no significant increase in inflammatory cytokines or microglial hyperactivation was observed in the brain. By day 21, neuroinflammation was detected, albeit with a slight delay, in the absence of adaptive immune cells. The colitis-induced neuroinflammation model provides insights into the fundamental immune mechanisms of the gut-brain axis and may contribute to developing immune cell therapies for IBD-induced neuroinflammation.

Background/Aims: The Korean guidelines for Helicobacter pylori treatment were revised in 2020, however, the extent of adherence to these guidelines in clinical practice remains unclear. Herein, we initiated a prospective, nationwide, multicenter registry study in 2021 to evaluate the current management of H.pylori infection in Korea. Methods: This interim report describes the adherence to the revised guidelines and their impact on firstline eradication rates. Data on patient demographics, diagnoses, treatments, and eradication outcomes were collected using a web-based electronic case report form. Results: A total of 7,261 patients from 66 hospitals who received first-line treatment were analyzed.The modified intention-to-treat eradication rate for first-line treatment was 81.0%, with 80.4% of the prescriptions adhering to the revised guidelines. The most commonly prescribed regimen was the 14-day clarithromycin-based triple therapy (CTT; 42.0%), followed by tailored therapy (TT; 21.2%), 7-day CTT (14.1%), and 10-day concomitant therapy (CT; 10.1%). Time-trend analysis demonstrated significant increases in guideline adherence and the use of 10-day CT and TT, along with a decrease in the use of 7-day CTT (all p<0.001). Multivariate logistic regression analysis revealed that guideline adherence was significantly associated with first-line eradication success (odds ratio, 2.03; 95% confidence interval, 1.61 to 2.56; p<0.001). Conclusions The revised guidelines for the treatment of H. pylori infection have been increasingly adopted in routine clinical practice in Korea, which may have contributed to improved first-line eradication rates. Notably, the 14-day CTT, 10-day CT, and TT regimens are emerging as the preferred first-line treatment options among Korean physicians.

Purpose: Considering the high disease burden and unique features of Asian patients with breast cancer (BC), it is essential to have a comprehensive view of genetic characteristics in this population. An institutional targeted sequencing platform was developed through the Korea Research-Driven Hospitals project and was incorporated into clinical practice. This study explores the use of targeted next-generation sequencing (NGS) and its outcomes in patients with advanced/metastatic BC in the real world. Materials and Methods: We reviewed the results of NGS tests administered to BC patients using a customized sequencing platform—FiRST Cancer Panel (FCP)—over 7 years. We systematically described clinical translation of FCP for precise diagnostics, personalized therapeutic strategies, and unraveling disease pathogenesis. Results: NGS tests were conducted on 548 samples from 522 patients with BC. Ninety-seven point six percentage of tested samples harbored at least one pathogenic alteration. The common alterations included mutations in TP53 (56.2%), PIK3CA (31.2%), GATA3 (13.8%), BRCA2 (10.2%), and amplifications of CCND1 (10.8%), FGF19 (10.0%), and ERBB2 (9.5%). NGS analysis of ERBB2 amplification correlated well with human epidermal growth factor receptor 2 immunohistochemistry and in situ hybridization. RNA panel analyses found potentially actionable and prognostic fusion genes. FCP effectively screened for potentially germline pathogenic/likely pathogenic mutation. Ten point three percent of BC patients received matched therapy guided by NGS, resulting in a significant overall survival advantage (p=0.022), especially for metastatic BCs. Conclusion Clinical NGS provided multifaceted benefits, deepening our understanding of the disease, improving diagnostic precision, and paving the way for targeted therapies. The concrete advantages of FCP highlight the importance of multi-gene testing for BC, especially for metastatic conditions.

Background/Aims: Patients with acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) typically have a poor prognosis; however, no effective treatment is available. In recent years, several retrospective studies have suggested the clinical benefits of direct hemoperfusion with a polymyxin B–immobilized fiber column (PMX-DHP) in patients with AE-IPF. Herein, we aimed to investigate the efficacy and safety of PMX-DHP treatment in patients with AE-IPF. Methods: Patients diagnosed with AE-IPF (n = 10) with a partial pressure of oxygen to fraction of inspiratory oxygen ratio (P/F ratio) > 100 were prospectively enrolled at a single center. PMX-DHP was performed twice for 6 hours (at 24-h intervals) at a flow rate of 80–100 mL/min, and steroid pulse therapy was concurrently administered (500 mg of methylprednisolone for 3 d). Results: The mean patient age was 67 years, and 80.0% were male. During the follow-up (median, 42.5 d; interquartile range, 16.0–174.0 d), seven (70.0%) patients died (including two who underwent transplantation); the in-hospital mortality rate was 70%, while the 30- and 90-day mortality rates were 50.0% and 70.0%, respectively. After 48 hours of PMX-DHP treatment, the P/F ratio improved (mean, 160.0 vs. 229.0; p = 0.054) and C-reactive protein level decreased (mean, 8.3 mg/dL vs. 3.5 mg/dL; p = 0.012). During hospitalization, no PMX-DHP–associated adverse events were observed. Conclusions Our results suggest that PMX-DHP treatment may be useful at improving oxygenation and reducing inflammation in patients with AE-IPF with acceptable safety profiles, however without affecting their prognosis.

Background/Aims: Patients with acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) typically have a poor prognosis; however, no effective treatment is available. In recent years, several retrospective studies have suggested the clinical benefits of direct hemoperfusion with a polymyxin B–immobilized fiber column (PMX-DHP) in patients with AE-IPF. Herein, we aimed to investigate the efficacy and safety of PMX-DHP treatment in patients with AE-IPF. Methods: Patients diagnosed with AE-IPF (n = 10) with a partial pressure of oxygen to fraction of inspiratory oxygen ratio (P/F ratio) > 100 were prospectively enrolled at a single center. PMX-DHP was performed twice for 6 hours (at 24-h intervals) at a flow rate of 80–100 mL/min, and steroid pulse therapy was concurrently administered (500 mg of methylprednisolone for 3 d). Results: The mean patient age was 67 years, and 80.0% were male. During the follow-up (median, 42.5 d; interquartile range, 16.0–174.0 d), seven (70.0%) patients died (including two who underwent transplantation); the in-hospital mortality rate was 70%, while the 30- and 90-day mortality rates were 50.0% and 70.0%, respectively. After 48 hours of PMX-DHP treatment, the P/F ratio improved (mean, 160.0 vs. 229.0; p = 0.054) and C-reactive protein level decreased (mean, 8.3 mg/dL vs. 3.5 mg/dL; p = 0.012). During hospitalization, no PMX-DHP–associated adverse events were observed. Conclusions Our results suggest that PMX-DHP treatment may be useful at improving oxygenation and reducing inflammation in patients with AE-IPF with acceptable safety profiles, however without affecting their prognosis.

Emerging evidence suggests that systemic inflammation may play a critical role in neurological disorders. Recent studies have shown the connection between inflammatory bowel diseases (IBD) and neurological disorders, revealing a bidirectional relationship through the gut-brain axis.Immunotherapies, such as Treg cells infusion, have been proposed for IBD. However, the role of adaptive immune cells in IBD-induced neuroinflammation remains unclear. In this study, we established an animal model for IBD in mice with severe combined immune-deficient (SCID), an adaptive immune deficiency, to investigate the role of adaptive immune cells in IBD-induced neuroinflammation. Mice were fed 1%, 3%, or 5% dextran sulfate sodium (DSS) for 5 days. We measured body weight, colon length, disease activity index (DAI), and crypt damage. Pro-inflammatory cytokines were measured in the colon, while microglial morphology, neuronal count, and inflammatory cytokines were analyzed in the brain. In the 3% DSS group, colitis symptoms appeared at day 7, with reduced colon length and increased crypt damage showing colitis-like symptoms. By day 21, colon length and crypt damage persisted, while DAI showed recovery. Although colonic inflammation peaked at day 7, no significant increase in inflammatory cytokines or microglial hyperactivation was observed in the brain. By day 21, neuroinflammation was detected, albeit with a slight delay, in the absence of adaptive immune cells. The colitis-induced neuroinflammation model provides insights into the fundamental immune mechanisms of the gut-brain axis and may contribute to developing immune cell therapies for IBD-induced neuroinflammation.

Background/Aims: The Korean guidelines for Helicobacter pylori treatment were revised in 2020, however, the extent of adherence to these guidelines in clinical practice remains unclear. Herein, we initiated a prospective, nationwide, multicenter registry study in 2021 to evaluate the current management of H.pylori infection in Korea. Methods: This interim report describes the adherence to the revised guidelines and their impact on firstline eradication rates. Data on patient demographics, diagnoses, treatments, and eradication outcomes were collected using a web-based electronic case report form. Results: A total of 7,261 patients from 66 hospitals who received first-line treatment were analyzed.The modified intention-to-treat eradication rate for first-line treatment was 81.0%, with 80.4% of the prescriptions adhering to the revised guidelines. The most commonly prescribed regimen was the 14-day clarithromycin-based triple therapy (CTT; 42.0%), followed by tailored therapy (TT; 21.2%), 7-day CTT (14.1%), and 10-day concomitant therapy (CT; 10.1%). Time-trend analysis demonstrated significant increases in guideline adherence and the use of 10-day CT and TT, along with a decrease in the use of 7-day CTT (all p<0.001). Multivariate logistic regression analysis revealed that guideline adherence was significantly associated with first-line eradication success (odds ratio, 2.03; 95% confidence interval, 1.61 to 2.56; p<0.001). Conclusions The revised guidelines for the treatment of H. pylori infection have been increasingly adopted in routine clinical practice in Korea, which may have contributed to improved first-line eradication rates. Notably, the 14-day CTT, 10-day CT, and TT regimens are emerging as the preferred first-line treatment options among Korean physicians.