Objective: CT-P13, a biosimilar of infliximab, is widely used for treating ankylosing spondylitis (AS). However, the formation of anti-drug antibodies (ADAs) can reduce its efficacy. This study aimed to identify risk factors associated with high ADA levels in AS patients treated with CT-P13. Methods: A prospective observational study enrolled patients with intravenous CT-P13. Clinical data and disease activity was assessed at baseline, 24 weeks, and 54 weeks after CT-P13 treatment. Blood concentrations of CT-P13 and ADAs were measured at 24 and 54 weeks, and their correlation was investigated. Patients were grouped by ADA levels at 54 weeks. Univariable and multivariable logistic regression identified factors associated with high ADA concentrations. Results: A total of 34 patients was enrolled. Significant decreases in Bath Ankylosing Spondylitis Disease Activity Index and Bath Ankylosing Spondylitis Functional Index scores were observed relative to baseline after 24 weeks of CT-P13 therapy. Serum concentrations of CT-P13 and ADA levels increased following treatment. The median serum CT-P13 concentration was 17.6 [12.8, 22.7] µg/mL at 24 weeks and 23.5 [11.7, 34.2] µg/mL at 54 weeks. ADA levels were 6.7 [6.5, 9.1] AU/mL at 24 weeks and 11.4 [9.0, 28.4] AU/mL at 54 weeks. The serum concentrations of CT-P13 and ADA exhibited a negative correlation. In multivariable analysis, current smoking was associated with high ADA production at 54 weeks. Conclusion Smoking is identified as a significant risk factor for elevated ADAs in AS patients treated with CT-P13. The findings underscore the importance of smoking-cessation strategies in the management of AS patients.

Background: and Purpose Previous research on patients with acute ischemic stroke (AIS) has shown a 0.5% incidence of major gastrointestinal bleeding (GIB) requiring blood transfusion during hospitalization. The existing literature has insufficiently explored the long-term incidence in this population despite the decremental impact of GIB on stroke outcomes. Methods: We analyzed the data from a cohort of patients with AIS admitted to 14 hospitals as part of a nationwide multicenter prospective stroke registry between 2011 and 2013. These patients were followed up for up to 6 years. The occurrence of major GIB events, defined as GIB necessitating at least two units of blood transfusion, was tracked using the National Health Insurance Service claims data. Results: Among 10,818 patients with AIS (male, 59%; mean age, 68±13 years), 947 (8.8%) experienced 1,224 episodes of major GIB over a median follow-up duration of 3.1 years. Remarkably, 20% of 947 patients experienced multiple episodes of major GIB. The incidence peaked in the first month after AIS, reaching 19.2 per 100 person-years, and gradually decreased to approximately one-sixth of this rate by the 2nd year with subsequent stabilization. Multivariable analysis identified the following predictors of major GIB: anemia, estimated glomerular filtration rate <60 mL/min/1.73 m2 , and a 3-month modified Rankin Scale score of ≥4. Conclusion Patients with AIS are susceptible to major GIB, particularly in the first month after the onset of AIS, with the risk decreasing thereafter. Implementing preventive strategies may be important, especially for patients with anemia and impaired renal function at stroke onset and those with a disabling stroke.

Cerebellar ataxia, neuropathy, and vestibular areflexia syndrome (CANVAS) is a neurodegenerative disorder caused by a biallelic expansion of pentanucleotide repeats in the RFC1 gene. Previous studies have reported up to 22% of patients with late-onset ataxia harbor this pathogenic repeat expansion. Despite its relatively high prevalence, CANVAS is often underdiagnosed because the disease is not well recognized and genetic testing is not performed in clinical practice. Here, we present a patient with characteristic clinical features, confirmed by genetic testing.

Background: Despite the critical importance of sleep medicine within neurology, notable gaps in education and clinical practice persist among neurologists. This study aims to explore the extent of involvement and the challenges faced by Korean neurologists in sleep medicine, focusing on awareness of polysomnography training program, the operation of sleep study facilities, and educational exposure. Methods: An online survey collected responses from 233 neurologists, focusing on their demographics, knowledge of and involvement in sleep medicine, operation of sleep study facilities, and participation in residency training. Results: The findings indicated that 84.9% of neurologists were aware of polysomnography training program, primarily through professional societies. Nonetheless, 15.1% reported unfamiliarity with these initiatives, with 72.7% of this subgroup expressing interest in sleep medicine yet lacking access to information. In terms of clinical practice, 74 neurologists operated sleep study facilities, with 63% intending to expand. Key operational challenges included staff management, maintaining patient volumes, and inadequate institutional support. Among respondents from teaching hospitals, only 36 out of 114 reported active resident involvement in sleep study interpretations, predominantly hindered by excessive workloads and insufficient staffing. Conclusions A significant number of neurologists have an interest in sleep medicine; however, substantial challenges impede effective education and clinical practice. These results underscore the need for improved educational resources and institutional support to enhance the growth and effectiveness of sleep medicine practices among neurologists.

Radiofrequency ablation (RFA) is a minimally invasive treatment modality used as an alternative to surgery in patients with benign thyroid nodules, recurrent thyroid cancers (RTCs), and primary thyroid microcarcinomas. The Korean Society of Thyroid Radiology (KSThR) initially developed recommendations for the optimal use of RFA for thyroid tumors in 2009 and revised them in 2012 and 2017. As new meaningful evidence has accumulated since 2017 and in response to a growing global interest in the use of RFA for treating malignant thyroid lesions, the task force committee members of the KSThR decided to update the guidelines on the use of RFA for the management of RTCs based on a comprehensive analysis of current literature and expert consensus.

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.

The crossed occlusion is unstable, and for the treatment of such occlusal conditions, it is recommended to form a balance of occlusal force between the arch in contact with occlusal contact, to secure stable vertical support by symmetrically placing the implants in the posterior area, and it is necessary to improve the distorted occlusal plane, to have a regular check-up and to check whether the occlusal conditions are maintained stably after treatment. In this case, in order to resolve unstable occlusal condition in patient with crossed occlusion, the existing occlusal vertical dimension was maintained at the state of wearing the dentures, and the implant placement positions were planned based on the diagnostic waxup, and then the implants were placed using a surgical guides, and after the temporary prostheses stage, the final fixed prostheses were fabricated by incorporating the temporary prostheses form adapted by the patient to develop a stable vertical support, and finally the anterior maxillary region was restored with implant-supported removable partial denture. In this case, the patient adapted well without discomfort during the four-month follow-up and satisfactory aesthetic and functional clinical results were obtained, leading to this report.

Background/Aims: Multiple myeloma (MM) predominantly affects elderly individuals, but studies on older patients with MM are limited. The clinical characteristics and survival outcomes of patients with MM aged 80 years or over were retrospectively analyzed. Methods: This retrospective multicenter study was conducted to investigate the clinical characteristics, treatment patterns, and survival outcomes of patients aged 80 years or over who were newly diagnosed with MM at five academic hospitals in Daegu, Korea, between 2010 and 2019. Results: A total of 127 patients with a median age of 83 years (range, 80–93 yr) were enrolled: 52 (40.9%) with Eastern Cooperative Oncology Group Performance Status (ECOG PS) > 2, 84 (66.1%) with International Staging System (ISS) stage III disease, and 93 (73.2%) with a Charlson comorbidity index (CCI) > 4. Chemotherapy was administered to 86 patients (67.7%). The median overall survival was 9.3 months. Overall survival was significantly associated with ECOG PS > 2 (HR 2.26, 95% CI 1.43–3.59), ISS stage III (HR 1.99, 95% CI 1.18–3.34), and chemotherapy (HR 0.34, 95% CI 0.21–0.55). There was no statistically significant difference in event-free survival according to the type of anti-myeloma chemotherapy administered. The early mortality (EM) rate was 28.3%. Conclusions Even in patients with MM aged 80 years or over, chemotherapy can result in better survival outcomes than supportive care. Patients aged ≥ 80 years should not be excluded from chemotherapy based on age alone. However, reducing EM in elderly patients with newly diagnosed MM remains challenging.

The crossed occlusion is unstable, and for the treatment of such occlusal conditions, it is recommended to form a balance of occlusal force between the arch in contact with occlusal contact, to secure stable vertical support by symmetrically placing the implants in the posterior area, and it is necessary to improve the distorted occlusal plane, to have a regular check-up and to check whether the occlusal conditions are maintained stably after treatment. In this case, in order to resolve unstable occlusal condition in patient with crossed occlusion, the existing occlusal vertical dimension was maintained at the state of wearing the dentures, and the implant placement positions were planned based on the diagnostic waxup, and then the implants were placed using a surgical guides, and after the temporary prostheses stage, the final fixed prostheses were fabricated by incorporating the temporary prostheses form adapted by the patient to develop a stable vertical support, and finally the anterior maxillary region was restored with implant-supported removable partial denture. In this case, the patient adapted well without discomfort during the four-month follow-up and satisfactory aesthetic and functional clinical results were obtained, leading to this report.