• Pediatric Infection and Vaccine
• /
• v.29 no.2
• /
• pp.77-83
• /
• 2022

A small proportion of children with coronavirus disease 2019 (COVID-19) develop severe pneumonia. We reported the severe COVID-19 pneumonia in children aged <18 years with COVID-19 treated with remdesivir and dexamethasone from August 2021 to November 2021 by a retrospective review of their medical records. Eight children were included (5 males and 3 females). Their median age was 16 years (range: 9 to 17 years) and their median body mass index was 30.5 kg/m² (range: 22.8-38.5 kg/m²). All patients had fever and dyspnea with hypoxia. Chest radiographic findings were variable and included diffuse or multifocal consolidation, nodules, and ground-glass opacities in the lungs. After receiving intravenous remdesivir and dexamethasone, 7 of the 8 children experienced an improvement in their symptoms within 2 days. In our case series, obesity was present in 6 out of 8 children with severe COVID-19 pneumonia.

• Pediatric Infection and Vaccine
• /
• v.28 no.3
• /
• pp.144-148
• /
• 2021

Purpose: Nonpharmaceutical measures, such as social distancing, have resulted in unintended consequences, including a decrease in the incidence of childhood diseases. This study aimed to estimate the impact of social distancing on the incidence of febrile seizure (FS) in Korea using nationally representative data. Methods: We used claims data from the Health Insurance Review and Assessment Service, a single-payer database capturing >95% of the Korean population. The database included any inpatient encounter with a FS diagnosis from January 2010 to September 2020 for those aged 0-5 years old. We aggregated the monthly number of cases to estimate the incidence per 100,000 patient-years in 2020 (January 1 to September 30) for the same periods in 2010-2019. Results: The incidence of FS in 2020 ranged from 113 per 100,000 (95% confidence interval [CI], 108-118 per 100,000) in January to 27 per 100,000 (95% CI, 25-30 per 100,000) in September, whereas the average FS incidence in 2010-2019 ranged from 116 per 100,000 (95% CI, 112-121 per 100,000) in January to 101 per 100,000 (95% CI, 97-106 per 100,000) in September. Conclusions: The incidence of FS decreased by -38% in 2020, suggesting that social distancing contributed towards decreasing the incidence of FS.

• Pediatric Infection and Vaccine
• /
• v.28 no.3
• /
• pp.173-180
• /
• 2021

After initial reports of multisystem inflammatory syndrome in children (MIS-C) in April 2020 in Europe, this disease has been known to occur in children with recent history of coronavirus disease 2019 (COVID-19) and most cases have been reported in Europe and the Unites States of America. We report a case of a 14-year-old girl who was diagnosed with MIS-C with acute myocarditis and successfully treated with intravenous immunoglobulin (IVIG), methylprednisolone, and anakinra. At initial presentation, she had persistent high fever, generalized rash, generalized swelling, abdominal pain, and low blood pressure. She showed a remarkably elevated level of inflammation and cardiac enzyme markers and had a previous history of COVID-19 5 weeks before the initial presentation. After extensive work up, other infectious and non-infectious causes were excluded. She was diagnosed with MIS-C and initially treated with IVIG and high-dose methylprednisolone; however, despite treatment, her heart function deteriorated and coronary artery dilatation progressed. Therefore, anakinra, an interleukin-1 receptor antagonist, was administered on hospital day 6, after which her cardiac function exhibited improvement. She was discharged on hospital day 19 without any symptoms, and follow-up echocardiography after 1 month revealed fully recovered heart function with normal coronary arteries.

• Pediatric Infection and Vaccine
• /
• v.29 no.3
• /
• pp.147-154
• /
• 2022

The clinical severity of coronavirus disease 2019 (COVID-19) in children is usually mild. Most of the affected patients completely recovered from COVID-19 before being released from approximately 7-day quarantine. However, children with comorbidities are at risk of more severe disease and adverse outcomes. We report three cases of COVID-19-affected adolescents with underlying chronic respiratory difficulty due to neurologic diseases who showed sudden clinical aggravations at the time of discharge, even after full clinical improvement. Patient 1 is a 17-year-old boy with Ullrich congenital muscular dystrophy who had cardiopulmonary arrest 9 days after the initial COVID-19 symptoms. Patient 2 is a 17-year-old girl with intracerebral hemorrhage with infarction in bed-ridden status who had cardiopulmonary arrest 11 days after the initial symptoms. Patient 3 is a 12-year-old boy with intraventricular hemorrhage with hydrocephalus in bed-ridden status who showed multiorgan failure 10 days after the initial symptoms. Remdesivir, dexamethasone, and empirical antibiotics were administered with mechanical ventilation and intensive unit care. Among the three patients, two (patients 1 and 3) were alive, and one (patient 2) expired. Clinicians caring for adolescents with chronic neurologic and/or pulmonary disease should keep in mind that these patients could have sudden deterioration after recovery from the acute phase of COVID-19 around or after the time of discharge.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.26 no.2
• /
• pp.32-36
• /
• 2022

Purpose There are reports that the COVID-19 vaccine causes false positive uptake of axillary lymph nodes. Therefore, this paper intends to evaluate the change in SUVmax of axillary lymph nodes with the period after the COVID-19 vaccination. Materials and Methods In 134 breast cancer patients who were tested for ¹⁸F-FDG PET/CT at Severance hospital, 3.7 MBq/kg of ¹⁸F-FDG was intravenously injected and scanned for 2 minutes per bed after 60 minutes. The equipment was Discovery 600 (GE Healthcare, MI, USA). The period was divided into four groups, 0 to 2 weeks, 3 to 6 weeks, 7 to 10 weeks, and 11 weeks or more. SUVmax was measured after checking the uptake of axillary lymph nodes on the ipsilateral side of vaccination and the Kruskal-Wallis test was performed using SPSS Statistics 28 (IBM Corp., Armonk, NY, USA). Results From 0 to 2 weeks groups to 11 weeks or more group, the average of SUVmax was measured in the order of 5.52, 2.85, 1.82, and 1.7. As a result of the Kruskal-Wallis test, there was a significant difference between 0 to 2 weeks group from all other groups (P < 0.05), and there was no significant difference between the remaining three groups. Conclusion The SUVmax of axillary lymph nodes decreased over the period after the COVID-19 vaccination and no significant difference was found after 3 weeks of vaccination. Therefore, it is recommended to record COVID-19 vaccination information before examination.

• Journal of Life Science
• /
• v.33 no.1
• /
• pp.64-72
• /
• 2023

Despite several advances in identification of cardiac transcription factors, there are still needs to find new bioactive molecules that promote cardiomyogenesis from stem cells to highly efficient myocardial differentiation. We analyzed Illumina expression microarray data of mouse embryonic stem cells (mESCs)-derived cardiomyocytes. 276 genes were upregulated (≥ 4fold) in mESCs-derived cardiomyocytes compared undifferentiated ESCs. Secreted phosphoprotein 2 (Spp2) is one of candidates and is known to inhibit bone morphogenetic protein 2 (BMP2) signal transduction as a pseudoreceptor for BMP2. However, its function in cardiomyogenesis is unknown. We confirmed that Spp2 expression increased during the differentiation into functional cardiomyocytes using mESCs, TC-1/Kh2 and E14. Interestingly, Spp2 secretion transiently increased 3 days after formation of embryoid bodies (EBs), indicating that the extracellular secretion of Spp2 is involved in the differentiation of ESCs into cardiomyocytes. To characterize Spp2, we performed experiments using the C2C12 mouse myoblast cell line, which has the property of shifting the differentiation pathway from myoblastic to osteoblastic by treatment with BMP2. Similar to the differentiation of ESCs, transcription of Spp2 increased as C2C12 myoblasts differentiated into myotubes. In particular, Spp2 secretion increased dramatically in the early stage of differentiation. Furthermore, treatment with Spp2-Flag recombinant protein promoted the differentiation of C2C12 myoblasts into myotubes. Taken together, we suggest a novel bioactive protein Spp2 that differentiates ESCs into cardiomyocytes. This may be useful for understanding the molecular pathways of cardiomyogenesis and for experimental or clinical promotion of stem cell therapy for ischemic heart diseases.

• Journal of Life Science
• /
• v.33 no.8
• /
• pp.605-611
• /
• 2023

Recently, sporadic cases of human infection by genetic reassortants of H7Nx influenza A viruses have been reported; such viruses have also been continuously isolated from avian species. In this study, A/wild bird/South Korea/sw-anu/2023, a novel reassortant of the H7N1 avian influenza virus, was analyzed using full-genome sequencing and molecular characterization. Phylogenetic analysis showed that A/wild bird/South Korea/sw-anu/2023 belonged to the Eurasian lineage of H7Nx viruses. The polymerase basic (PB)2, PB1, polymerase acidic (PA), and nucleoprotein (NP) genes of these viruses were found to be closely related to those of avian influenza viruses isolated from wild birds, while the hemagglutinin (HA), neuraminidase (NA), matrix (M), and nonstructural (NS) genes were similar to those of avian influenza viruses isolated from domestic ducks. In addition, A/wild bird/South Korea/sw-anu/2023 also had a high binding preference for avian-specific glycans in the solid-phase direct binding assay. These results suggest the presence of a new generation of H7N1 avian influenza viruses in wild birds and highlight the reassortment of avian influenza viruses found along the East Asian-Australasian flyway. Overall, H7Nx viruses circulate worldwide, and mutated H7N1 avian viruses may infect humans, which emphasizes the requirement for continued surveillance of the H7N1 avian influenza virus in wild birds and poultry.

• Pediatric Infection and Vaccine
• /
• v.30 no.2
• /
• pp.97-103
• /
• 2023

Kawasaki disease (KD) is an acute, systemic inflammatory disorder that often targets coronary arteries. Being the common cause of acquired heart disease in children, timely diagnosis and intravenous immunoglobulin treatment are crucial. However, it is challenging for physicians to diagnose KD if it presents with atypical manifestations. We report the case of a 5-year-old boy who initially presented with appendicitis; after an appendectomy, he had a prolonged fever. He was finally diagnosed with atypical KD and successfully recovered after intravenous immunoglobulin treatment. Through a literature review, we found 21 cases of appendicitis associated with KD. In most cases, the patients were male with a mean age of 5.3 years. Most had higher proportions of incomplete KD and coronary artery complications than expected for typical KD. In conclusion, appendicitis could be a rare complication of KD; therefore, multidisciplinary cooperation and early recognition of atypical KD are essential for timely diagnosis.

• Pediatric Infection and Vaccine
• /
• v.30 no.2
• /
• pp.55-61
• /
• 2023

Purpose: Urinary tract infections (UTIs) pose a significant disease burden in children. This study aims to determine whether a short-course regimen is non-inferior to a standard-course regimen in children with UTIs without complication and presence of bacteremia, and to define, in the optimal way possible, the term "short-course" in this context. Methods: We conducted a rapid systematic review of research up to April 2021 in PubMed, Embase, and Cochrane databases. We included studies that compared clinical outcomes in pediatric UTIs treated with short-course(≤4 days) or standard (≥5-7 days) courses. Results: Our analysis suggests that short-course regimes have equivalent efficacy to standard-course regimens, with similar clinical cure rates and recurrence rates. All 10 studies comparing the clinical cure rates of short- and standard-course regimens reported comparable outcomes. The study evaluating renal scarring indicated no inferiority of short-course regimens compared to standard-course ones. Regarding UTI relapse, 8 out of 10 studies reported no significant difference in outcomes between short- and standard-course regimens. Conclusions: Our results purpose that short-course UTI regimens of 6 days or less are just as effective as standard-term regimens of 7 days or more in terms of infection cure and prevention of recurrence. Considering the equivalent rates of clinical cure and relapse between short- and standard-course regimens, it could be inferred that short-course regimens might be a more optimal strategy for managing pediatric UTIs without increasing the risk of complications.

• Pediatric Infection and Vaccine
• /
• v.30 no.2
• /
• pp.62-72
• /
• 2023

Purpose: A change is expected in the pattern of respiratory viruses including human coronavirus (HCoV) after the coronavirus disease 2019 (COVID-19) outbreak. Accordingly, identifying the distribution of respiratory viruses before the COVID-19 outbreak is necessary. Methods: We retrospectively analyzed the results of samples of nasal swabs collected from children under aged ≤18 years who were hospitalized at Myongji Hospital, Gyeonggi-do due to acute respiratory infections from 2017 to 2019. Viruses were detected by real-time reverse transcription polymerase chain reaction (RT-PCR). Results: Out of 3,557 total patients, 3,686 viruses were detected with RT-PCR including coinfections. Of the 3,557 patients, 2,797 (78.6%) were confirmed as PCR-positive. Adenovirus and human rhinovirus (hRV) were detected throughout the year, and human enterovirus was most detected during summer. Respiratory syncytial virus, influenza virus, and HCoV were prevalent in winter. In patients with croup, parainfluenza virus was most frequently detected, followed by hRV and HCoV. The PCR positive rate in summer and winter differed significantly. Conclusions: Respiratory virus patterns in northwestern Gyeonggi-do were not much different from previously reported data. The data reported herein regarding respiratory virus epidemiological information before the COVID-19 outbreak can be used for use in comparative studies of respiratory virus patterns after the COVID-19 outbreak.