Da Eun Roh

Background: Neurodevelopmental disorders (NDDs) are frequently encountered in pediatric neurology clinics. However, their extensive genetic heterogeneity often limits the diagnostic yield of standard diagnostic tests, highlighting the need for comprehensive genomic approaches.Purpose: This study aimed to evaluate the diagnostic utility of whole exome sequencing (WES) and whole genome sequencing (WGS) in children with unexplained NDDs and assess the clinical relevance of the genomic findings.Methods: We retrospectively reviewed the medical records of 64 pediatric patients with NDDs who underwent WES or WGS between March 2018 and November 2024. Clinical data, neuroimaging and electroencephalography findings, and the results of previous genetic tests were analyzed. The diagnostic yield was calculated, and clinical characteristics were compared between patients with and without a genetically confirmed diagnosis. Patients were categorized as genetically confirmed (positive) when a definitive molecular diagnosis was identified through WES or WGS and as not genetically confirmed (negative) when no causative variant was detected.Results: A definitive molecular diagnosis was achieved in 25 of 64 patients (39.1%). Diagnostic yields were 37.5% and 33.3% for WES and WGS, respectively. Most variants showed autosomal dominant (n=13) inheritance, followed by X-linked (n=9) and autosomal recessive (n=3) patterns. Novel variants accounted for 57.7% of the pathogenic or likely pathogenic variants. A positive family history was significantly associated with a higher diagnostic yield (20.0% vs. 2.6%, P=0.030), while prematurity was more common in the negative group (33.3% vs. 8.0%, P=0.032). Three WES-negative patients were later diagnosed using chromosomal microarray analysis (CMA) or repeat expansion testing.Conclusion: WES and WGS are effective diagnostic tools for pediatric NDDs. Phenotype re-evaluation and the selective use of genetic tests such as CMA and repeat expansion analysis enhance diagnostic yield.

Background: The Act on Life-Sustaining Treatment (LST) for patients at the end of life (the Korean LST Decision Act), implemented in the Republic of Korea in February 2018, has led to changes in the end-of-life decision-making (EOLDM) process in children. This study aimed to investigate changes in pediatric EOLDM process and LST practices since the Korean LST Decision Act. Methods: This retrospective cohort study included 107 patients who died at Kyungpook National University Children’s Hospital from January 2015 to December 2020. Patients were divided into two groups: pre-law (January 2015–January 2018, n = 55) and post-law (February 2018–December 2020, n = 52). We analyzed medical records for EOLDM process, patient characteristics, intensive care unit (ICU) admission, documentation types, and LST withholding or withdrawal decisions. Results: After the Korean LST Decision Act, the median total hospitalization duration decreased significantly (14 days [IQR, 3–80] vs. 6 days [IQR, 2–18], p = 0.020), as did the median ICU length of stay (3 days [IQR 1–33] vs. 2.5 days [IQR 1–10.3], p = 0.002). The time from admission to end-of-life decision documentation was significantly shorter in group 2 (6 days [IQR 1–31] vs. 4 days [IQR 1–9], p = 0.027). The use of physician orders for life-sustaining treatment (POLST) documents increased (0% to 33.3%), while do-not-resuscitate (DNR) orders decreased (85.3% to 16.7%). Notably, LST withdrawal decisions increased from 0% to 27.8% (p = 0.001) in the post-legislation period. Conclusions: The Korean LST Decisions Act has led to significant changes in the EOLDM process for terminally ill children, including earlier decision-making, increased use of POLST documents, more frequent LST withdrawal decisions, and shorter hospital and ICU stays. These findings suggest a shift towards more structured and timely end-of-life care discussions in pediatric settings.

Paraquat is a fatal, rapid-acting, nonselective herbicide. Despite the restriction of production and sales of the herbicide in Korea since 2012, already purchased paraquat can incur poisoning. This article describes a 25-month-old boy who accidentally ingested old paraquat on a rural road. After initial decontamination at 2 outside hospitals, he was transferred to the intensive care unit. Given the urine drug concentration of 20,000 ng/mL 2 hours after the intoxication, he received charcoal hemoperfusion and continuous venovenous hemofiltration to enhance the excretion of the herbicide. In 36 hours after intoxication, it was not detected in the urine. The boy was discharged uneventfully on day 8. This case highlights the importance of hemoperfusion in paraquat poisoning.

As adolescents started to be vaccinated against coronavirus disease 2019 (COVID-19), suspected myocarditis and pericarditis related to the vaccine were reported in adolescents. According to the Korea Disease Control and Prevention Agency (KDCA), 2,796,270 persons aged 12–18 years were fully vaccinated by December 8. Among these, 9223 adverse events were reported (0.33%). We aimed to elucidate the clinical courses and short-term outcomes for adolescents aged 12–18 with cardiac symptoms and suspected myo- or peri-carditis related to COVID-19 vaccination in South Korea. Methods: We retrospectively collected data on patients ≤ 18 years of age who had suspected myocarditis or pericarditis within 30 days of COVID-19 vaccination, from July 2021 to January 2022. Results: We reported on 40 adolescents in different South Korean provinces at two centers. Twenty-six cases (65%) were male, and the median age was 16 years (range, 13–18; IQR 14.5–17). Twenty-five cases (62.5%) occurred at the first dose, and fifteen (37.5%) occurred after the second dose. Symptoms started at a median of 2 days (range 0–29 days; IQR 1–5 days) after vaccination. The patients were treated with nonsteroidal anti-inflammatory drugs (77.5%), intravenous immunoglobulin (2.5%), glucocorticoids (20%), colchicine (5%), or no therapy (15%). Five patients (12.5%) required intensive care unit admission; one patient needed inotropic/vasoactive support. No patients required extracorporeal membrane oxygenation or died. The median hospital stay was one day (range 0–8 days; IQR 0–2 days). Twenty-one patients (52.5%) had an abnormal electrocardiogram; among these, seven patients had an elevated ST segment, six patients (15%) had decreased ejection fraction (<55%), and LV function was completely recovered in all of them. Conclusions: Most cases of suspected myocarditis after COVID-19 vaccination in adolescents ≤ 18 years had mild symptoms and clinical courses, as well as a complete recovery. Further studies are needed to evaluate long-term outcomes.

We aimed to evaluate the utility of the serum ferritin level as an early screening test of Kawasaki disease with macrophage activation syndrome (KD-MAS). We analyzed the serum ferritin levels on the first day of admission and the clinical progress of patients diagnosed with complete or incomplete KD. Of the 158 patients, 5 were diagnosed with KD-MAS. Conjunctival injection was significantly more frequent in KD group (p = 0.035), although there were no significant differences in other clinical features. On the first day of admission, the serum ferritin level in the KD-MAS group was >500 ng/mL, which was higher than that in the KD group (p = 0.001). In the KD-MAS group, total bilirubin, triglyceride, and lactate dehydrogenase (LDH) were significantly higher, and erythrocyte sedimentation rate (ESR), total protein, albumin, and fibrinogen were significantly lower than the KD group (p < 0.05). Four patients were diagnosed with MAS within 7 days after admission, and 4 (80%) patients with KD-MAS survived. In conclusion, carrying out an early ferritin screening test is important in patients with principal clinical features that may suspect KD. We propose to include ferritin level in the primary laboratory test to differentiate between KD with and without MAS early.

Background: Acetylsalicylic acid (ASA) is part of the recommended treatment of Kawasaki disease (KD). Controversies remain regarding the optimal dose of ASA. We aimed to evaluate the impact of different doses of ASA on inflammation control while minimizing adverse effects in the acute phase treatment of KD. Methods: The enrolled 323 patients with KD were divided into three groups according to ASA dose: moderate-dose (30–50 mg/kg/day), high-dose (80–100 mg/kg/day), and non-ASA. Results: High-dose ASA group showed a significantly shorter duration of fever from the start of treatment to remission than other groups. Baseline level and delta score of interleukin (IL)-1, IL-6, IL-10, tumor necrosis factor-α, and transforming growth factor β were not statistically different among the groups. The number of patients who received additional treatments in the non-ASA group was more than other groups. Coronary artery dilatation was not significantly different among the groups. One patient with high-dose ASA was diagnosed with Reye syndrome. Conclusion: Different doses of ASA did not show any differences in changes of inflammatory bio-makers and cytokines. However, high-dose ASA showed occurrence of Reye syndrome, and non-ASA showed intravenous immunoglobulin refractoriness. We suggest that moderate-dose ASA may be beneficial for the treatment of patients in the acute phase of KD.

Kawasaki disease, also known as mucocutaneous lymph node syndrome, is a common form of vasculitis in childhood. Among the recent trends in Kawasaki disease, it is notable that the prevalence rate is increasing, and the proportion of “incomplete” Kawasaki disease is also increasing. A delayed diagnosis with prolonged fever can cause complications, such as coronary artery aneurysm and decreased myocardial contractility. These complications might lead to significant morbidity and mortality. Kawasaki disease is diagnosed when the patient meets the principal criteria for clinical symptoms. Following the diagnostic criteria can prevent overdiagnosis but lead to missing of the incomplete form of the disease. Therefore, it is important to accurately understand Kawasaki disease. As the coronavirus disease 2019 (COVID-19) pandemic continues, concerns about a novel severe Kawasaki-like disease in children related to COVID-19 emerges. Indeed, there have been several reports of Kawasaki-like disease related to COVID-19 in children. Kawasaki disease is no longer rare and is often encountered at hospitals. This paper will provide useful and accurate information on Kawasaki disease.