A retrospective study of SARS-CoV-2 antibodies in children with allergies.

BACKGROUND: The dynamics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in children are continually changing. We conducted a survey of pediatric allergy patients attending our department to determine the prevalence of antibodies against SARS-CoV-2 in children. METHODS: A retrospective study was performed among children aged <11 years, referred to a pediatric allergy department between February 2020 and January 2022 with a chief complaint of allergy. The data of children with blood examination findings were retrospectively studied. Qualitative testing for anti-SARS-CoV-2 IgG and IgM antibodies was performed using a SARS-CoV-2 rapid antibody test. Participants were retested 1 year later to evaluate changes in antibody levels. RESULTS: In total, 310 patients with a median age of 26 months (interquartile range: 11.6-58.4 months) and male/female ratio of 1.31 were included. A total of 32 patients tested positive for anti-SARS-CoV-2 IgG or IgM antibodies. No differences were observed in the severity of allergic disease. The prevalence of antibodies was higher among children enrolled in preschool or school (odds ratio: 13.19, 95% confidence interval; 2.30-249.7). A total of 66.7% of patients underwent follow-up testing. The antibody positivity rate increased between the first and second testing, but this was not related to the number of medical visits or the severity of allergic disease. CONCLUSION: Antibody prevalence in children was low but increased during the study period. The majority of children who tested positive for SARS-CoV-2 antibodies did not have a history of coronavirus disease 2019, suggesting that most infections were subclinical.

Evidence of off-label inhalation therapy on pediatric asthma practice in Japan.

BACKGROUND: In Japan, many asthma inhalers do not have formal approval for use in the pediatric population because of the lack of domestic data. In real-world settings, however, numerous off-label medications are prescribed. Currently, the nature of off-label prescriptions of asthma inhalers on pediatric patients in Japan remains unclear. METHODS: Using public open-source national medical claims data, we investigated the real-world descriptive epidemiology of off-label prescriptions for asthma inhalers for pediatric patients. We obtained the number of off-label prescriptions of formulations for patients aged 0-14 years from anonymously summarized prescription data for a 7-year period starting from April 2014. The actual prescription numbers and their chronology over time were then analyzed. RESULTS: In 2019, 143,439 asthma inhalers were used off label in children and adolescents. Overall, 96.1% were inhaled corticosteroids (ICSs) or long-acting beta stimulants (LABAs), and 3.9% were high-dose ICS. Of ICSs and LABAs, 18.8% were off-label prescriptions. The total number of off-label ICS/LABA prescriptions and their percentage relative to the overall formulations gradually decreased but a notable disparity was observed among inhaler types. CONCLUSIONS: There was a surprisingly large number of off-label prescriptions of asthma inhalers in the pediatric population in Japan. The proper use of ICSs/LABAs and expansion of insurance coverage should be advocated to reduce off-label use.

Notch signaling contributes to the establishment of sustained unresponsiveness to food allergens by oral immunotherapy.

BACKGROUND: Oral immunotherapy (OIT) aims to establish desensitization and sustained unresponsiveness (SU) in patients with food allergy by ingestion of gradually increasing doses of specific food allergens. However, little is known about the mechanisms by which OIT induces SU to specific allergens. OBJECTIVES: We investigated the role of Notch signaling, which controls cell fate decisions in many types of immune cells in the induction of SU by OIT treatment. METHODS: Two types of mouse models, ovalbumin-induced food allergy and OIT, were generated. To elucidate the role of Notch signaling in OIT-induced SU, mice were intraperitoneally injected with the Notch signaling inhibitor N-[(3,5-difluorophenyl)acetyl]-l-alanyl-2-phenylglycine-1,1-dimethylethyl ester during the OIT treatment period. RESULTS: Ovalbumin-sensitized mice were desensitized and also had SU induced by OIT treatment, whereas repeated challenges with ovalbumin caused the development of severe allergic reactions in ovalbumin-sensitized mice. Administration of N-[(3,5-difluorophenyl)acetyl]-l-alanyl-2-phenylglycine-1,1-dimethylethyl ester to mice during the OIT treatment period inhibited the establishment of SU to ovalbumin but did not affect the induction of desensitization. OIT induced a systemic expansion of IL-10-producing CD4+ T cells, including TH2 cells, and myeloid-derived suppressor cells (MDSCs), particularly the monocytic MDSC subpopulation. Inhibition of Notch signaling prevented the OIT-induced expansion of those cells. In vitro cultures of bone marrow cells showed that Notch signaling directly promoted the generation of monocytic MDSCs. In addition, the contribution of MDSCs to OIT-induced SU was confirmed by MDSC depletion with the anti-Gr1 antibody. CONCLUSION: Notch signaling contributes to the establishment of SU induced by OIT through systemic expansion of immunosuppressive cells, such as IL-10-producing CD4+ T cells and MDSCs.

The influence on renal function of ibuprofen treatment for patent ductus arteriosus in extremely low birthweight infants.

BACKGROUND: Ibuprofen (IBU) has been used recently for the treatment of patent ductus arteriosus (PDA) in Japan. We aimed to investigate the efficacy and adverse events of IBU and compare them with those of indomethacin (IND) as PDA treatment for extremely low-birthweight infants (ELBWIs), focusing on short-term renal function. METHODS: A case-control study was conducted on 16 ELBWIs. The data from eligible patients were divided into two groups. Ten patients had undergone IND treatment (IND group) between January 2017 and June 2018, whereas six had undergone IBU treatment (IBU group) for PDA between July 2018 and December 2018. The IND group received 0.1 mg/kg/12h IND IV infusion for three doses, whereas the IBU group received 10 mg/kg IV IBU infusion followed by 5 mg/kg/day for 2 days. We compared the efficacy for PDA closure and renal impairment between the two groups. RESULTS: No significant differences in primary closure rates and the PDA ligation required were observed between the two groups. No significant differences were observed between the incidence of intraventricular hemorrhage and gastrointestinal complications in both groups. Changes in urine volume (%) in the IBU group were significantly higher than in the IND group at 24-36 h post-administration. The urinary L-type fatty acid binding protein concentration level at 7 days of life was significantly lower in the IBU group than in the IND group. CONCLUSION: Although IBU was comparable to IND in PDA closure rate, IBU was superior to short-term renal injury in ELBWIs.