Background: Sanger sequencing is a technology used to identify the gene sequence variants causing rare genetic disorders. However, designing and implementing a proficiency scheme for Sanger sequencing-based genetic testing is challenging because many molecular diagnostic laboratories are running sequencing tests for tens to hundreds of target genes. As such, we aimed to design and implement a method-based proficiency testing (PT) method for Sanger sequencing and to assess its feasibility in Korea. Methods: A pathogenic low density lipoprotein receptor (LDLR) variant was chosen as the positive PT material, and material without an LDLR variant was used as the negative PT material. We distributed the two PT materials with primer pair sets to 17 molecular diagnostic laboratories nationwide.We calculated the correct results (%) for variation type, zygosity, nucleotide change, amino acid change, variant classification, and clinical interpretation. Results: Fourteen laboratories responded to the survey. The results for the two PT materials were 100% correct for all evaluation points including variant type, zygosity, nucleotide change, amino acid change, variant classification, and clinical interpretation. Conclusions This pilot PT survey demonstrates a feasibility of using method-based PT for assessing the Sanger sequencing performance of molecular diagnostic laboratories in Korea.

Objective: To analyze costs and cost-effectiveness of transforaminal endoscopic thoracic discectomy (TETD) for the treatment of symptomatic thoracic disc herniation (TDH) and compare it with open microdiscectomy (MD). Methods: This retrospective cohort study included patients who underwent TETD or MD for symptomatic TDH and had a minimum follow-up of 1 year. Cost analysis included direct costs (primary and secondary hospital costs), indirect costs (lost wages due to work absence), total costs (direct + indirect), and cost-effectiveness (cost per quality-adjusted life year [QALY] and incremental cost-effectiveness ratio [ICER]). Clinical outcomes included patient-reported outcome measures (Oswestry Disability Index [ODI], 36-item Short Form health survey [SF-36]), QALY gained, and reoperation and readmission rates at 1 year. TETD and MD groups were compared for outcome measures. Results: A total of 111 patients (57 TETD, 54 MD) were included. The direct ($6,270 TETD vs. $7,410 MD, p < 0.01), indirect costs ($1,250 TETD vs. $1,450 MD, p < 0.01), total costs ($7,520 TETD vs. $8,860 MD, p < 0.01), and cost per QALY ($31,333 TETD vs. $44,300 MD, p < 0.01) were significantly lower for TETD compared to MD. ICER of TETD was found to be -$33,500. At 1 year, TETD group showed significantly greater improvement in ODI (46% vs. 36%, p < 0.01) and SF-36 (64% vs. 53%, p < 0.01) and significantly greater QALY gained (0.24 vs. 0.2, p < 0.01) compared to MD group. No significant difference was found in reoperation and readmission rates. Conclusion TETD demonstrated significantly better clinical outcomes, lower overall costs, and better cost-effectiveness than MD in appropriately selected patients of symptomatic TDH.

Objective: To analyze costs and cost-effectiveness of transforaminal endoscopic thoracic discectomy (TETD) for the treatment of symptomatic thoracic disc herniation (TDH) and compare it with open microdiscectomy (MD). Methods: This retrospective cohort study included patients who underwent TETD or MD for symptomatic TDH and had a minimum follow-up of 1 year. Cost analysis included direct costs (primary and secondary hospital costs), indirect costs (lost wages due to work absence), total costs (direct + indirect), and cost-effectiveness (cost per quality-adjusted life year [QALY] and incremental cost-effectiveness ratio [ICER]). Clinical outcomes included patient-reported outcome measures (Oswestry Disability Index [ODI], 36-item Short Form health survey [SF-36]), QALY gained, and reoperation and readmission rates at 1 year. TETD and MD groups were compared for outcome measures. Results: A total of 111 patients (57 TETD, 54 MD) were included. The direct ($6,270 TETD vs. $7,410 MD, p < 0.01), indirect costs ($1,250 TETD vs. $1,450 MD, p < 0.01), total costs ($7,520 TETD vs. $8,860 MD, p < 0.01), and cost per QALY ($31,333 TETD vs. $44,300 MD, p < 0.01) were significantly lower for TETD compared to MD. ICER of TETD was found to be -$33,500. At 1 year, TETD group showed significantly greater improvement in ODI (46% vs. 36%, p < 0.01) and SF-36 (64% vs. 53%, p < 0.01) and significantly greater QALY gained (0.24 vs. 0.2, p < 0.01) compared to MD group. No significant difference was found in reoperation and readmission rates. Conclusion TETD demonstrated significantly better clinical outcomes, lower overall costs, and better cost-effectiveness than MD in appropriately selected patients of symptomatic TDH.

Background: Group B Streptococcus (GBS) is one of the leading causes of neonatal earlyonset sepsis, resulting in high mortality and significant comorbidity. Intrapartum penicillin prophylaxis is recommended for pregnant women with GBS colonization to prevent vertical transmission. For pregnant women at high risk of anaphylaxis to penicillin, clindamycin is recommended only if the susceptibility of GBS isolates has been identified. We retrospectively examined the GBS detection rate and clindamycin resistance among Korean women of reproductive age over the last 20 years. Methods: Microbiologic studies using vaginal, vaginal–rectal or vaginal–perianal swabs from female patients 15–49 years of age during 2003–2022 were reviewed. Annual GBS detection rates and clindamycin resistance rates were calculated. The study period was divided into two periods (period 1, 2003–2015; period 2, 2016–2022) based on the introduction of universal culture-based GBS screening in our center in 2016. GBS detection rates and clindamycin resistance rates were compared between the periods using χ2 tests. Results: A total of 14,571 women were tested 16,879 times and GBS was isolated in 1,054 tests (6.2%), with 423 clindamycin-resistant isolates (40.1%). The GBS detection rate increased from 3.4% (301/8,869) in period 1 to 9.4% (2,753/8,010) in period 2 (P < 0.001). Even during period 1, the GBS detection rate was higher in 2009–2015 compared to 2003–2008 (P < 0.001). Clindamycin resistance rates have remained at similar levels since 2009, which were 39.5% (199/301) in period 1 and 40.2% (303/753) in period 2 (P = 0.833). Conclusion This study demonstrated that GBS detection rates in Korean women of reproductive age significantly increased almost three times during the twenty years of the study period, with a persistently high clindamycin resistance rate of up to 40%.

Background: This study aimed to identify key priorities for the development of guidelines for information and communication technology (ICT)-based patient education tailored to the needs of patients with rheumatic diseases (RDs) in the Republic of Korea, based on expert consensus. Methods: A two-round modified Delphi study was conducted with 20 rheumatology, patient education, and digital health literacy experts. A total of 35 items covering 7 domains and 18 subdomains were evaluated. Each item was evaluated for its level of importance, and the responses were rated on a 4-point Likert scale. Consensus levels were defined as “high” (interquartile range [IQR] ≤ 1, agreement ≥ 80%, content validity ratio [CVR] ≥ 0.7), "Moderate" (IQR ≥ 1, agreement 50–79%, CVR 0.5–0.7), and "Low" (IQR > 1, agreement < 50%, CVR < 0.5). Results: Strong consensus was reached for key priorities for developing guidelines in areas such as health literacy, digital health literacy, medical terminology, user interface, and user experience design for mobile apps. Chatbot use and video (e.g., YouTube) also achieved high consensus, whereas AI-powered platforms such as ChatGPT showed moderate-to-high agreement. Telemedicine was excluded because of insufficient consensus. Conclusion The key priorities identified in this study provide a foundation for the development of ICT-based patient education guidelines for RDs in the Republic of Korea.Future efforts should focus on integrating digital tools into clinical practice to enhance patient engagement and improve clinical outcomes.

Background: Shortage of organ donors in the Republic of Korea has become a major problem. To address this, it has been questioned whether heart transplant (HTx) allocation should be modified to reduce priority of older patients. We aimed to evaluate post-HTx outcomes according to recipient age and specific pre-HTx conditions using a nationwide prospective cohort. Methods: We analyzed clinical characteristics of 628 patients from the Korean Organ Transplant Registry who received HTx from January 2015 to December 2020. Enrolled recipients were divided into three groups according to age. We also included comorbidities including ambulatory status. Non-ambulatory status was defined as pre-HTx support with either extracorporeal membrane oxygenation, continuous renal replacement therapy, or mechanical ventilation. Results: Of the 628 patients, 195 were < 50 years, 322 were 50–64 years and 111 were ≥ 65years at transplant. Four hundred nine (65.1%) were ambulatory and 219 (34.9%) were nonambulatory. Older recipients tended to have more comorbidities, ischemic cardiomyopathy, and received older donors. Post-HTx survival was significantly lower in older recipients (P = 0.025) and recipients with non-ambulatory status (P < 0.001). However, in contrast to non-ambulatory recipients who showed significant survival differences according to the recipient’s age (P = 0.004), ambulatory recipients showed comparable outcomes (P = 0.465). Conclusion Our results do not support use of age alone as an allocation criterion. Transplant candidate age in combination with some comorbidities such as non-ambulatory status may identify patients at a sufficiently elevated risk at which suitability of HTx should be reconsidered.

Background: The increasing incidence and mortality rates of tuberculosis among older individuals who suffer from multiple morbidities and are vulnerable to malnutrition are major obstacles to efforts to eradicate tuberculosis in the Republic of Korea. Herein, we identified the factors associated with mortality during anti-tuberculosis treatment in patients with pulmonary tuberculosis. Methods: We conducted a case-control study and extracted data from the database of a multi-center prospective observational cohort study in Korea. Among the participants with rifampicin-susceptible pulmonary tuberculosis, the survival group was defined as those who successfully completed treatment within one year, whereas the mortality group was defined as those who died during treatment. Univariable and multivariable logistic regression analyses were performed to identify factors associated with TB mortality. Results: Among 1,119 participants with pulmonary TB registered between 2019 and 2021, 799 and 59 were grouped in the survival and mortality groups, respectively. Age, positive smear results, alarming symptoms, nutrition risk score, Charlson comorbidity index score, and initial standard treatment regimen were significant based on univariable analysis and were selected for the multivariable logistic regression model. Nutrition risk score (adjusted odds ratio, 2.44; 95% confidence interval, 1.72–3.48) and Charlson comorbidity index score (adjusted odds ratio, 1.62; 95% confidence interval, 1.35–1.94) remained statistically significant in the multivariate analysis. Conclusion Nutritional status and comorbidities at baseline were identified as important factors associated with mortality in patients with pulmonary tuberculosis.

Background: While the clinical course of radiation-induced meningioma (RIM) is considered to be more aggressive than that of sporadic meningioma (SM), the genetic predisposition for RIM is not established well. The present study aimed to analyze the clinical and genetic characteristics of RIMs to increase understanding of the tumorigenesis and prognosis of RIMs. Methods: We investigated a database of 24 patients who met the RIM criteria between January 2000 and April 2023. Genetic analysis through next-generation sequencing with a targeted gene panel was performed on 10 RIM samples. Clinical, radiological, and pathological parameters were evaluated with genetic analyses. Results: The median ages for receiving radiotherapy (RT) and RIM diagnosis were 8.0 and 27.5 years, respectively, with an interval of 17.5 years between RT and RIM diagnosis. RIMs tended to develop in non-skull bases and multifocal locations. Most primary pathologies included germ cell tumors and medulloblastoma. The tumor growth rate was 3.83 cm 3 per year, and the median doubling time was 0.8 years. All patients underwent surgical resection of RIMs. The histological grade of RIMs was World Health Organization grade 1 (64%) or 2 (36%). RIMs showed higher incidences in young-age (63%), high-dose (75%), and extendedfield (79%) RT groups. The recurrence rate was 21%. Genetic analysis revealed NF2 one copy loss in 90% of the patients, with truncating NF2 mutations and additional copy number aberrations in grade 2 RIMs. TERT promoter mutation and CDKN2A/B deletion were not identified. Notably, loss of H3K27me3 was identified in 26% of RIMs. H3K27me3 loss was associated with a higher prevalence of grade 2 RIMs (67%) and high recurrence rates (33%). Conclusion The study reveals a higher prevalence of high-grade tumors among RIMs with more rapid growth and higher recurrences than SMs. Genetically, RIMs are primarily associated with NF-2 alterations with chromosomal abnormalities in grade 2 tumors, along with a higher proportion of H3K27me3 loss.

It is difficult to determine a cause of bile duct stricture and dilatation. Eosinophilic cholangitis, a rare benign condition, may be one cause of bile duct stricture and dilatation. It can be evaluated using various methods of histopathology, radiographs, endoscopy, and hematologic findings. Treatment generally involves steroid therapy which can lead to improvement. This case report will discuss eosinophilic cholangitis, emphasizing that while it can easily be overlooked but should be considered in differential diagnoses.