Background: Primary Merkel cell carcinoma of the salivary gland is currently not listed in the World Health Organization classification. However, cases of Merkel cell type neuroendocrine carcinomas of the salivary gland with perinuclear cytokeratin 20 positivity have been intermittently reported. We here investigated the clinicopathologic features of additional cases. Methods: Data of four cases of Merkel cell type small cell neuroendocrine carcinoma of the salivary gland were retrieved. To confirm the tumors’ primary nature, clinical records and pathologic materials were reviewed. Optimal immunohistochemical staining was performed to support the diagnosis. Results: All tumors were located in the parotid gland. Possibilities of metastasis were excluded in all cases through a meticulous clinicopathological review. Tumor histology was consistent with the diagnosis of small cell neuroendocrine carcinoma. Tumors’ immunohistochemical phenotypes were consistent with Merkel cell carcinoma, including Merkel cell polyomavirus large T antigen positivity in two of the four cases. Conclusions Merkel cell carcinomas can originate in salivary glands and are partly associated with Merkel cell polyomavirus infection as in cutaneous Merkel cell carcinomas.

Purpose: Congenital hypothyroidism (CH) is a major preventable cause of intellectual disability, particularly in very low birth weight (VLBW) infants, who are at increased risk due to hypothalamic-pituitary-thyroid axis immaturity. Early differentiation between transient CH (TCH) and permanent CH (PCH) is crucial to optimize L-thyroxine (LT4) treatment duration. This study aimed to determine the incidence of PCH among Korean VLBW infants and to identify clinical factors that may aid in distinguishing TCH from PCH. Methods: This retrospective cohort study included VLBW infants diagnosed with CH and treated with LT4 at a single tertiary neonatal intensive care unit between 2011 and 2020. Infants requiring LT4 beyond 3 years were classified as PCH, while those who discontinued earlier were considered TCH. Clinical characteristics, neonatal morbidities, and thyroid-related parameters were compared between the groups. Results: Among 1,292 VLBW infants, 122 (9.4%) were diagnosed with CH. After excluding deaths and those lost to follow-up, 73 infants were included in the final analysis (TCH, n=50; PCH, n=23). The PCH group had a significantly higher mean gestational age and greater LT4 requirements at both 12 and 36 months of age. Major anomalies were more frequently observed in PCH infants, including congenital heart defects. In multivariate analysis, higher gestational age, the presence of major anomalies, screening thyroid-stimulating hormone (TSH) >10 μIU/mL, and higher LT4 dose at 36 months were significantly associated with PCH. Conclusion The incidence of PCH in Korean VLBW infants was relatively higher than that reported in previous studies studies. Screening TSH level and LT4 dose requirements may support individualized follow-up and help distinguish PCH from TCH.

Purpose: This study aims to develop and test the psychometric properties of a scale for measuring the continuity of care specific to home health care patients in the context of Korean long-term care insurance services. Methods: In phase 1, the initial item pool was created based on the concept analysis results using a literature review and in-depth interviews. Phase 2 evaluated the psychometric properties of the scale in the survey conducted in 2021 using a sample of 202 receiving longterm care visiting nursing services. Exploratory factor analysis (EFA) was used to examine the construct validity. An internal consistency was examined using Cronbach’s α. Known group validity and criterion validity were assessed. Results: The EFA suggested five factors: therapeutic relationship, coordination of care, service availability, customized care plan, and consistency in service provision. The internal consistency reliability of the continuity of care scale was satisfactory (Cronbach’s α=.96). Known-group validity was established by comparing the continuity of care scores for high utilizers of home-visiting nursing services and low utilizers of home-visiting nursing services. Criterion validity was confirmed through the correlation between the developed scale and the performance of the visiting nurse service scale. Conclusion The developed scale was found to be reliable and relatively valid for measuring the patient’s perceived continuity of care within the Korean long-term care visiting nursing system.

With the increasing emphasis on diversity, equity, and inclusion (DEI) in organizations and institutions, academic societies in gastroenterology and hepatology are beginning to take actionable steps toward achieving DEI. The successful implementation of DEI initiatives leads to excellence in the field, improved patient outcomes, particularly in areas where health disparities are prevalent, and advances in the gastrointestinal discipline. Such implementation also results in a workforce that better reflects the growing diversity of the population. This review defines DEI and introduces the DEI policies and strategies adopted by the academic societies of gastroenterology in other countries. This paper proposes strategies to integrate DEI better into the Korean Society of Gastroenterology, emphasizing the importance of embedding DEI into the culture and strategic framework. The key strategies include establishing a DEI committee, setting clear targets, and conducting formal assessments to measure DEI progress. This study focused on enhancing workforce diversity, particularly among women and young doctors, and advocates for the need to support their academic development through male allyship and the promotion of equitable and inclusive academic cultures.

Gastrointestinal stromal tumors (GISTs) are rare mesenchymal neoplasms that mainly occur in the stomach and small intestine; those arising in the esophagus are rarer. A 54-year-old woman was referred to our hospital with a one-month history of dysphagia. Esophagogastroduodenoscopy (EGD), performed approximately five months earlier, had not revealed any specific findings. However, an EGD performed in our hospital showed the presence of a round, protruding lesion (approximately 40×30 mm in size), with a normal overlying mucosal surface, 35–39 cm from the upper incisor. Chest computed tomography (CT) revealed a large esophageal mass. Enucleation was performed on the esophageal mass, and a GIST was diagnosed using immunochemical staining. Imatinib mesylate administration was initiated two months postoperatively. The patient was stable, without any evident recurrence in the 8-month postoperative follow-up EGD and chest CT examinations. Therefore, physicians should consider that patients with worsening dysphagia may have an underlying organic condition, such as an acute increase in size of an esophageal GIST, even if recent examinations were unremarkable.

The LabGenius C-CT/NG-BMX assay (LabGenius CT/NG; BIOMEDUX, Gyeonggi, Republic of Korea) is a recently developed real-time PCR assay that can simultaneously detect the sexually transmitted pathogens Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) in genitourinary specimens. We evaluated the analytical performance of this assay in comparison with BD MAX CT/GC/TV (Becton Dickinson, Franklin Lakes, NJ, USA). The results of both assays were in nearly perfect agreement for the detection of CT and NG. LabGenius CT/NG demonstrated acceptable analytical performance, comparable with that of another commercially available kit, and provides a cost-effective option for detecting sexually transmitted pathogens in routine and follow-up testing.

Background: TP53 mutations are associated with poor prognosis in myelodysplastic neoplasm (MDS) and AML. The updated 5th WHO classification and International Consensus Classification (ICC) categorize TP53-mutated MDS and AML as unique entities. We conducted a multicenter study in Korea to investigate the characteristics of TP53-mutated MDS and AML, focusing on diagnostic aspects based on updated classifications. Methods: This study included patients aged ≥ 18 yrs who were diagnosed as having MDS(N = 1,244) or AML (N = 2,115) at six institutions. The results of bone marrow examination, cytogenetic studies, and targeted next-generation sequencing, including TP53, were collected and analyzed. Results: TP53 mutations were detected in 9.3% and 9.2% of patients with MDS and AML, respectively. Missense mutation was the most common, with hotspot codons R248/ R273/G245/Y220/R175/C238 accounting for 25.4% of TP53 mutations. Ten percent of patients had multiple TP53 mutations, and 78.4% had a complex karyotype. The median variant allele frequency (VAF) of TP53 mutations was 41.5%, with a notable difference according to the presence of a complex karyotype. According to the 5th WHO classification and ICC, the multi-hit TP53 mutation criteria were met in 58.6% and 75% of MDS patients, respectively, and the primary determinants were a TP53 VAF > 50% for the 5th WHO classification and the presence of a complex karyotype for the ICC. Conclusions Collectively, we elucidated the molecular genetic characteristics of patients with TP53-mutated MDS and AML, highlighting key factors in applying TP53 mutation-related criteria in updated classifications, which will aid in establishing diagnostic strategies.

Background: Citrin deficiency is an autosomal recessive disorder caused by pathogenic variants in SLC25A13, presenting with various age-dependent clinical phenotypes and a broad spectrum of severity. However, few studies have examined the frequency and prevalence of citrin deficiency. We aimed to analyze the carrier frequency and disease prevalence in East Asian populations and Koreans. Methods: We comprehensively reviewed the literature and conducted a cross-sectional study to analyze genomic databases, including the Genome Aggregation Database (gnomAD), Korean Variant Archive (KOVA), and Tohoku Medical Megabank Organization (ToMMo), to identify pathogenic SLC25A13 variants in East Asian populations. A founder 3-kilobase (kb) insertion in intron 16 of SLC25A13 was investigated using whole-genome sequencing data from 681 Koreans with the Linux grep command. Results: Twenty-three pathogenic SLC25A13 variants were identified, with c.852_855del being the most common. Analysis of data from 17,501 East Asian individuals in the gnomAD and ToMMo databases revealed a carrier frequency of 1 in 62 people. Analysis of data from 7,214 individuals in the gnomAD and KOVA databases revealed a carrier frequency of 1 in 86, corresponding to an estimated disease prevalence of 1 in 29,502.c.1177+1G > A was identified as the most prevalent pathogenic variant in Koreans. The 3 kb insertion in intron 16 was detected in three out of 681 individuals, indicating a carrier frequency of 1 in 228. Conclusions The high carrier frequency of citrin deficiency in East Asians highlights the need for enhanced genetic screening and counseling, particularly in Korea, providing a valuable reference for future studies on genetic diversity and pathogenic variants in this population.