Clinical Characteristics and Outcomes of Children With SARS-CoV-2 Infection During the Delta and Omicron VariantDominant Periods in Korea

Background@#Data on the clinical characteristics of pediatric patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant infection are limited. We aimed to evaluate the clinical features and outcomes of children with SARS-CoV-2 infection before and after omicron variant dominance in Korea. @*Methods@#A multicenter retrospective cohort study was conducted in hospitalized patients aged ≤ 18 years with laboratory-confirmed SARS-CoV-2 infection at five university hospitals in South Korea. The study periods were divided into the delta (from August 23, 2021 to January 2, 2022) and omicron (from January 30 to March 31, 2022). @*Results@#In total, 612 hospitalized patients were identified (211, delta; 401, omicron). During the omicron and delta periods, the proportions of individuals with serious illness (moderate, severe, and critical severity) were 21.2% and 11.8%, respectively (P = 0.034). Compared with the delta period, the proportions of patients with moderate illness increased significantly in the age groups of 0–4 years (14.2% vs. 3.4%) and 5–11 years (18.6% vs. 4.2%) during the omicron period. During the two periods, the proportions of patients with complex chronic diseases (delta, 16.0% vs. 4.3%, P = 0.040; omicron, 27.1% vs. 12.7%; P= 0.002), respiratory diseases except for asthma (delta, 8.0% vs. 0.0%, P = 0.013; omicron, 9.4% vs. 1.6%; P = 0.001), and neurologic diseases (delta, 28.0% vs. 3.2%, P < 0.001; omicron, 40.0% vs. 5.1%, P < 0.001) were significantly higher in patients with serious illness than in those with nonserious illness. During the delta period, the risk for serious illness was higher among patients with obesity (adjusted odds ratio [aOR], 8.18; 95% confidence interval [CI], 2.80–27.36) and neurologic diseases (aOR, 39.43; 95% CI, 6.90–268.3) and aged 12–18 years (aOR, 3.92; 95% CI, 1.46–10.85). However, the presence of neurologic disease (aOR, 9.80; 95% CI, 4.50–22.57) was the only risk factor for serious illness during the omicron period. During the omicron period, the proportions of patients with croup (11.0% vs. 0.5%) and seizures (13.2% vs. 2.8%) increased significantly compared with the delta period. @*Conclusion@#Compared with the delta period, the proportions of young children and patients with complex comorbidities were higher during the omicron period in Korea. Patients

Shift in Clinical Epidemiology of Human Parainfluenza Virus Type 3 and Respiratory Syncytial Virus B Infections in Korean Children Before and During the COVID-19 Pandemic:A Multicenter Retrospective Study

Background@#Parainfluenza virus type 3 (PIV3) and respiratory syncytial virus (RSV) B epidemics occurred in South Korea in late 2021. We investigated epidemiological changes of PIV3 and RSV B infections in Korean children before and during the coronavirus disease 2019 (COVID-19) pandemic. @*Methods@#In this multicenter retrospective study, we enrolled patients aged less than 19 years with PIV3 or RSV infection in four university hospitals from January 2018 to January 2022. Demographic and clinical data were extracted from the subject’s medical records and analyzed for each virus. @*Results@#A total of 652 children with PIV3 were identified including three epidemics: 216 in 2018, 260 in 2019, and 167 in 2021. Among 627 RSV B cases, 169 were identified in 2017/2018, 274 in 2019/2020, and 115 in 2021/2022. The peak circulation of PIV3 and RSV B epidemics were delayed by 6 and 2 months, respectively, in 2021, compared with those in the pre-COVID-19 period. The median age of PIV3 infections increased in 2021 (21.5 months in 2021 vs. 13.0–14.0 in 2018–2019; P < 0.001), whereas that of RSV B infections remained unchanged (3.6–4.0 months). During the COVID-19 pandemic, less frequent hospitalization rates were observed for both PIV3 and RSV B infections, but more children needed respiratory assistance for RSV B infection in 2021/2022 epidemic (32.5%) than before (14.7–19.4%, P = 0.014). @*Conclusion@#We observed changes in the epidemiology and clinical presentation of PIV3 and RSV B infections in Korean children during the COVID-19 pandemic.

Limited Benefit of Facility Isolation and the Rationale for Home Care in Children with Mild COVID-19

Considering the mild degree of coronavirus disease 2019 (COVID-19) in children and the enormous stress caused by isolation in unfamiliar places, policies requiring mandatory isolation at medical facilities should be reevaluated especially given the impact of the pandemic on the availability of hospital beds. In this study, we assessed the usefulness of facility isolation and the transmissibility of severe acute respiratory syndrome coronavirus 2 by infected children to uninfected caregivers in isolation units at a hospital and a residential treatment center in Seoul during August-November 2020. Fifty-three children were included and median age was 4 years (range, 0–18). All were mildly ill or asymptomatic and isolated for a median duration of 12 days. Thirty percent stayed home longer than 2 days before entering isolation units from symptom onset. Among 15 uninfected caregivers, none became infected when they used facemasks and practiced hand hygiene. The results suggest children with mild COVID-19 may be cared safely at home by a caregiver in conditions with adherence to the preventive measures of wearing facemasks and practicing hand hygiene.

Limited Benefit of Facility Isolation and the Rationale for Home Care in Children with Mild COVID-19

Considering the mild degree of coronavirus disease 2019 (COVID-19) in children and the enormous stress caused by isolation in unfamiliar places, policies requiring mandatory isolation at medical facilities should be reevaluated especially given the impact of the pandemic on the availability of hospital beds. In this study, we assessed the usefulness of facility isolation and the transmissibility of severe acute respiratory syndrome coronavirus 2 by infected children to uninfected caregivers in isolation units at a hospital and a residential treatment center in Seoul during August-November 2020. Fifty-three children were included and median age was 4 years (range, 0–18). All were mildly ill or asymptomatic and isolated for a median duration of 12 days. Thirty percent stayed home longer than 2 days before entering isolation units from symptom onset. Among 15 uninfected caregivers, none became infected when they used facemasks and practiced hand hygiene. The results suggest children with mild COVID-19 may be cared safely at home by a caregiver in conditions with adherence to the preventive measures of wearing facemasks and practicing hand hygiene.

Acute kidney injury associated with Yersinia pseudotuberculosis infection: Forgotten but not gone

BACKGROUND: Yersinia pseudotuberculosis is known to cause fever, gastroenteritis, or acute kidney injury (AKI). There have been several Y. pseudotuberculosis infection outbreaks to date associated with ingestion of contaminated food or unsterile water. While this disease was considered to have practically been eradicated with the improvement in public health, we encountered several cases of AKI associated with Yersinia infection. METHODS: We retrospectively collected data from medical records of patients with suspected Y. pseudotuberculosis infection who visited Seoul National University Children’s Hospital in 2017. RESULTS: There were nine suspected cases of Yersinia infection (six males and three females; age range 2.99–12.18 years). Among them, five cases occurred in May, and seven patients were residing in the metropolitan Seoul area. Three patients had history of drinking mountain water. Every patient first presented with fever for a median of 13 days, followed by gastrointestinal symptoms and oliguria. Imaging studies revealed mesenteric lymphadenitis, terminal ileum wall thickening, and increased renal parenchymal echogenicity. Creatinine levels increased to 5.72 ± 2.18 mg/dL. Urinalysis revealed sterile pyuria, proteinuria, and glycosuria. Oliguria continued for 4 to 17 days, and two patients required dialysis; however, all of them recovered from AKI. Mucocutaneous manifestations developed later. In the diagnostic work-up, Yersinia was isolated from the stool culture in one patient. Anti-Yersinia immunoglobulin (Ig) A and IgG were positive in 6 patients. CONCLUSION: Y. pseudotuberculosis infection is an infrequent cause of interstitial nephritis presenting with AKI. When a patient presents with fever, gastroenteritis, and AKI not resolving despite hydration, the clinician should suspect Y. pseudotuberculosis infection.

Epidural Abscess Caused by Eikenella corrodens in a Previously Healthy Child

Eikenella corrodens rarely causes invasive head and neck infections in immunocompetent children. We report a case of epidural abscess caused by E. corrodens in a previously healthy 13-year-old boy who presented with fever, headache, and vomiting. On physical examination upon admission, there was no neck stiffness, but discharge from the right ear was observed. Brain magnetic resonance imaging (MRI) revealed approximately 4.5-cm-sized epidural empyema on the right temporal lobe as well as bilateral ethmoid and sphenoid sinusitis, right mastoiditis, and right otitis media. During treatment with vancomycin and cefotaxime, purulent ear discharge aggravated, and on follow-up brain MRI, the empyema size increased to 5.6×3.4 cm with interval development of an abscess at the right sphenoid sinus. Burr hole trephination was performed, and foul-smelling pus was aspirated from the epidural abscess near the right temporal lobe. Pus culture yielded E. corrodens. Endoscopic sphenoidotomy was also performed with massive pus drainage, and the same organism was grown. The patient was treated with intravenous cefotaxime for 3 weeks and recovered well with no other complications. Therefore, E. corrodens can cause serious complications in children with untreated sinusitis.

A Case of Azathioprine Induced Severe Myelosuppression and Alopecia Totalis in IgA Nephropathy

Azathioprine is commonly used as immunosuppressive therapy for various inflammatory diseases including chronic glomerulonephritis. Myelosuppression is a common side effect of azathioprine, resulting in the need for dose reduction. However, severe pancytopenia or alopecia is not often encountered. Here, we report a case of severe myelosuppression, and alopecia totalis that occurred after azathioprine treatment in a patient with IgA nephropathy. A 10-year-old boy with IgA nephropathy was treated with oral deflazacort and later with azathioprine. After 4 weeks, the patient complained of hair loss, and despite a dose reduction in azathioprine, he developed bone marrow suppression and alopecia totalis in two weeks. The blood indices and alopecia of the patient had returned to normal after azathioprine withdrawal and 3 consecutive doses of granulocyte colony-stimulating factor. We suggest that physicians remain vigilant to the side effects of azathioprine. Unusual hair loss after azathioprine treatment might suggest a defect in the metabolism of the drug, warranting the discontinuation of azathioprine to prevent more severe side effects.