Background: Community acquired lower respiratory tract infection (LRTI) is a leading cause for hospitalization in children and important cause for antibiotic prescription. We aimed to describe the aetiology of LRTI in children and analyse factors associated with bacterial or viral infection. Methods: Patients aged < 19 years with a diagnosis of LRTI were identified from the Observational Medical Outcomes Partnership Common Data Model Database of Seoul National University Bundang Hospital from January 2005–July 2019, and their clinical characteristics were obtained from the electronic medical records and retrospectively reviewed. Results: Among 5,924 cases of LRTI, 74.2% were pneumonia and 25.8% were bronchiolitis/ bronchitis. Patients’ median age was 1.8 (interquartile range, 3.1) years and 79.9% were < 5 years old. Pathogens were identified in 37.8%; 69.1% were viral and 30.9% were bacterial/ Mycoplasma pneumoniae. Respiratory syncytial virus was most common (70.9%) among viruses and M. pneumoniae (94.6%) was most common among bacteria. Viral LRTI was associated with winter, age < 2 years, rhinorrhoea, dyspnoea, lymphocytosis, thrombocytosis, wheezing, stridor, chest retraction, and infiltration on imaging. Bacteria/ M. pneumoniae LRTI was associated with summer, age ≥ 2 years, fever, decreased breathing sounds, leucocytosis, neutrophilia, C-reactive protein elevation, and positive imaging findings (consolidation, opacity, haziness, or pleural effusion). Conclusion In children with LRTI, various factors associated with viral or bacterial/ M. pneumoniae infections were identified, which may serve as guidance for antibiotic prescription.

Background: Improving β-cell function can lead to remission in some patients with type 2 diabetes mellitus (T2DM). However, research on pharmacotherapy-induced remission in youth-onset T2DM remains scarce. Our study aimed to identify the clinical characteristics of pediatric patients who experience remission. Methods: We retrospectively reviewed 88 pediatric patients with T2DM followed for at least 1 year at Seoul National University Bundang Hospital between 2013 and 2023. Remission was defined as a glycosylated hemoglobin (HbA1c) level less than 6.5% for at least 3 months after ceasing glucose-lowering pharmacotherapy. Results: Among 88 patients (60 males, 68.2%) diagnosed at an average age of 14.4±2.1 years, 19 patients (21.6%) achieved remission after a median duration of 1.4 years. The remission group had a larger proportion of males (89.5% vs. 62.3%, P=0.024) and a lower urinary albumin-to-creatinine ratio (ACR) at diagnosis (P=0.011). They also showed lower HbA1c levels at 1 year and more significant changes in HbA1c and body mass index (all P<0.05). Higher urinary ACR levels correlated with a longer duration to achieve remission (hazard ratio, 0.928; P= 0.013). In three of the 19 remission patients (15.8%), recurrence occurred after a median of 1.5 years. Conclusion Among Korean youth with T2DM, 21.6% achieved remission after a median duration of 1.4 years.Those who experienced remission were predominantly male, had lower ACR at diagnosis, and had significant weight loss within the first year. Further investigation into the factors influencing remission and long-term outcomes is essential.

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: In Korea, the absence of a modified physical activity (PA) questionnaire specifically tailored for Koreans hinders the accurate assessment of PA among individuals with spinal cord injury (SCI). This study aimed to evaluate PA levels in individuals with SCI using a modified PA questionnaire and to provide insights into their PA patterns in Korea. Methods: A self-reported questionnaire was developed by revising and adapting the Korean version of the International Physical Activity Questionnaire (K-IPAQ) during an advisory meeting. Between April and June 2023, 176 individuals with SCI from metropolitan areas in Korea were recruited to assess their weekly PA. PA was quantified in Metabolic Equivalent Task-min/week (MET-min/week) by multiplying the reported PA duration. Results: The average PA level among individuals with SCI in Korea was 2,907.2±194.8 MET-min/week. By intensity, high-intensity activities accounted for 2,760.0±280.5 MET-min/week, moderate-intensity activities for 1,148.8±89.0 MET-min/week, and low-intensity activities for 1,869.4±110.3 MET-min/week. Approximately half of the participants met the World Health Organization (WHO) recommendations for PA. Conclusion Although Korean individuals with SCI demonstrated higher average PA levels compared to findings from other countries and the WHO recommendations, only about half of the participants met the WHO’s guidelines. These results underscore the need to strengthen efforts to promote PA participation among individuals with SCI.

Objective: We aimed to investigate the effectiveness of buspirone as an adjunctive therapy for alleviating anxiety symptoms in patients with depressive disorders who are already taking antidepressants. Methods: This was an open-label prospective multicenter non-interventional observational study conducted over 12 weeks. We enrolled 180 patients diagnosed with depressive disorders according to DSM-5 criteria and Hamilton Anxiety Rating Scale (HAMA) scores ≥ 18. Participants were already taking selective serotonin reuptake inhibitors or serotoninnorepinephrine reuptake inhibitors and were prescribed adjunctive buspirone. Efficacy was assessed using HAMA, Hamilton Depression Rating Scale (HAMD), Clinical Global Impression Scale-Improvement, Clinical Global Impression Scale-Severity, Sheehan Disability Scale (SDS), and WHO-5 Well-Being Index. Results: The efficacy analysis included 161 patients. HAMA scores decreased significantly from 25.2 ± 6.7 at baseline to 15.4 ± 8.6 at 12 weeks (p ＜ 0.001), whereas HAMD scores decreased from 19.4 ± 4.6 to 12.7 ± 5.7 (p ＜ 0.001).WHO-5 and SDS scores showed significant improvements. The HAMA response rate was 39.1% and the remission rate was 13.7% at 12 weeks. Adverse drug reactions were reported in 3.7% of participants. Subgroup analyses showed no significant differences in treatment response based on buspirone dosage, baseline anxiety/depression severity, or benzodiazepine use. Conclusion Adjunctive buspirone therapy effectively improved anxiety symptoms in depressed patients taking antidepressants, regardless of baseline symptom severity or buspirone dosage. The treatment was well-tolerated with few adverse events. Future studies using a control group are needed.

Background: This study aimed to assess the severity of postoperative delirium (PD) in elderly patients who underwent reverse total shoulder arthroplasty (rTSA) for irreparable massive rotator cuff tears (mRCTs) under general anesthesia (GA) compared to those under interscalene block (IB). Methods: Forty elderly patients aged 65 years or older diagnosed with an irreparable mRCT who underwent rTSA were included in the prospective case-controlled study. Of these, 20 patients were operated under GA and the other 20 under IB. The average age was 77.1 years (range, 65–95 years). The severity of delirious symptoms was evaluated by the Delirium Rating Scale–revised–98 (DRS) score from the patients or guardians before the surgery and at 0, 3, and 7 days and 1, 3, and 6 months after the surgery and compared between the 2 groups. Results: Immediately after surgery, the visual analog scale score difference between the groups was statistically significant, with the GA group at 6.25 (standard deviation, ± 0.85) and the IB group at 3.80 (± 0.62) (p < 0.001). On the day of operation, the mean DRS score in the GA and IB groups were 9.10 (± 5.63) and 6.60 (± 5.33), respectively (p = 0.157). On day 3 of surgery, the mean DRS score in the GA group peaked to 9.95 (± 8.73), while in the IB group, it declined to 6.40 (±5.81) (p = 0.138). After 3 days, DRS scores showed a decreasing trend in both groups. When comparing the mean change (∆) from the preoperative baseline scores to the postoperative values, the ∆DRS score was significantly higher with 4.15 (± 4.53) points in the GA group as compared to 1.30 (± 1.92) in the IB group (p = 0.014). Conclusions IB can be an attractive and efficient anesthetic choice in preventing PD for elderly patients undergoing rTSA for irreparable mRCTs. The IB group showed lower DRS scores and a peak on day 0 compared to the higher DRS scores and peak on day 3 in the GA group. Additionally, IB showed less pain than GA.

Radiation-induced cavernous malformations (RICMs) are rare but significant late complications of highdose radiation therapy, particularly in young survivors of brain tumors. This report presents two cases of RICMs following aggressive multimodal treatment, including surgery, chemotherapy, and radiation therapy. Case 1 was a 22-year-old male patient with medulloblastoma treated with craniospinal irradiation, tumor bed boost, and tandem autologous peripheral blood stem cell transplantation. Approximately 8 years after treatment completion, routine follow-up imaging revealed a small focal hemorrhage in the right cerebellum, consistent with an RICM. The lesion was asymptomatic and managed conservatively with regular imaging, showing spontaneous resolution over time, with a significant size reduction noted 9 years post-treatment. Case 2 describes a 32-year-old male with an intracranial germinoma treated with whole-ventricular irradiation. Three years after treatment, the patient developed a symptomatic hemorrhagic RICM near a pre-existing developmental venous anomaly. Surgical resection and Gamma Knife Surgery stabilized the lesion; however, residual symptoms, including tremors and gait disturbances, persisted, affecting the patient’s daily activities. These cases illustrate the diverse clinical courses of RICMs, ranging from spontaneous resolution to the necessity of surgical intervention, and emphasize the importance of long-term surveillance and tailored management strategies for late-onset complications.

Background: Community acquired lower respiratory tract infection (LRTI) is a leading cause for hospitalization in children and important cause for antibiotic prescription. We aimed to describe the aetiology of LRTI in children and analyse factors associated with bacterial or viral infection. Methods: Patients aged < 19 years with a diagnosis of LRTI were identified from the Observational Medical Outcomes Partnership Common Data Model Database of Seoul National University Bundang Hospital from January 2005–July 2019, and their clinical characteristics were obtained from the electronic medical records and retrospectively reviewed. Results: Among 5,924 cases of LRTI, 74.2% were pneumonia and 25.8% were bronchiolitis/ bronchitis. Patients’ median age was 1.8 (interquartile range, 3.1) years and 79.9% were < 5 years old. Pathogens were identified in 37.8%; 69.1% were viral and 30.9% were bacterial/ Mycoplasma pneumoniae. Respiratory syncytial virus was most common (70.9%) among viruses and M. pneumoniae (94.6%) was most common among bacteria. Viral LRTI was associated with winter, age < 2 years, rhinorrhoea, dyspnoea, lymphocytosis, thrombocytosis, wheezing, stridor, chest retraction, and infiltration on imaging. Bacteria/ M. pneumoniae LRTI was associated with summer, age ≥ 2 years, fever, decreased breathing sounds, leucocytosis, neutrophilia, C-reactive protein elevation, and positive imaging findings (consolidation, opacity, haziness, or pleural effusion). Conclusion In children with LRTI, various factors associated with viral or bacterial/ M. pneumoniae infections were identified, which may serve as guidance for antibiotic prescription.

Background: Improving β-cell function can lead to remission in some patients with type 2 diabetes mellitus (T2DM). However, research on pharmacotherapy-induced remission in youth-onset T2DM remains scarce. Our study aimed to identify the clinical characteristics of pediatric patients who experience remission. Methods: We retrospectively reviewed 88 pediatric patients with T2DM followed for at least 1 year at Seoul National University Bundang Hospital between 2013 and 2023. Remission was defined as a glycosylated hemoglobin (HbA1c) level less than 6.5% for at least 3 months after ceasing glucose-lowering pharmacotherapy. Results: Among 88 patients (60 males, 68.2%) diagnosed at an average age of 14.4±2.1 years, 19 patients (21.6%) achieved remission after a median duration of 1.4 years. The remission group had a larger proportion of males (89.5% vs. 62.3%, P=0.024) and a lower urinary albumin-to-creatinine ratio (ACR) at diagnosis (P=0.011). They also showed lower HbA1c levels at 1 year and more significant changes in HbA1c and body mass index (all P<0.05). Higher urinary ACR levels correlated with a longer duration to achieve remission (hazard ratio, 0.928; P= 0.013). In three of the 19 remission patients (15.8%), recurrence occurred after a median of 1.5 years. Conclusion Among Korean youth with T2DM, 21.6% achieved remission after a median duration of 1.4 years.Those who experienced remission were predominantly male, had lower ACR at diagnosis, and had significant weight loss within the first year. Further investigation into the factors influencing remission and long-term outcomes is essential.

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.