Background The effects of a delayed diagnosis of asthma on lung function in children have not been well investigated. Therefore, a retrospective cohort study was conducted in a children’s hospital to analyse the effect of delayed diagnosis time on lung function in children with asthma. Methods We conducted a retrospective cohort study in Jinan Children's Hospital from January 1, 2010, to December 31, 2020. All children were divided into different groups according to the presence or absence of rhinitis, age at first onset (first coughing and wheezing attack) and delayed diagnosis duration (≤ 3 months, 3–12 months, 1–3 years, 3–5 years and > 5 years). Results A total of 1,014 children with asthma were included in this study. The median (quartile) delay in asthma diagnosis among all participants was 11 (2, 26) months. The shortest delay in diagnosis time was on the same day of onset, and the longest delay in diagnosis time was 10 years. The median (quartile) duration of delayed diagnosis was 10 (2, 26) months in 307 asthmatic children without rhinitis and 11 (2, 26) months in 707 children with asthma and rhinitis (P < 0.05). The delayed diagnosis time was shorter among female children than among male children (P < 0.05), and the first %predicted forced volume capacity (FVC%pred) results for females were higher than those for males (P = 0.036). The children whose age at first asthma onset was ≤ 3 years had a longer delayed diagnosis duration than those whose age at first onset was > 3 years (P < 0.05). The FVC%pred and %predicted forced expiratory volume in 1 s (FEV1%pred) in the first and second pulmonary function tests were significantly lower in the five delayed diagnosis groups (all P < 0.05). After standardised treatment for 3–6 months, FVC%pred showed a significant difference in the third test among the 5 groups (P < 0.05), but the other pulmonary function indices showed no significant difference. Logistic regression analysis showed that longer delay and young age of onset were associated with lower lung function (P < 0.05), whereas sex, rhinitis and eczema had no significant effects (all P > 0.05) on FVC%pred and FEV1%pred. Conclusion Although delayed asthma diagnosis can lead to lung function impairment in children with asthma, lung function can be improved quickly after standardised treatment. Therefore, early asthma diagnosis and standardised treatment are very important.

small airway indicators, which was lacking in previous studies [1][2][3]. Pediatricians should focus on changes in lung function as well as the clinical control of asthma. We also found that BMI, onset at 1-3 y of age, a longer time interval of delayed diagnosis, and a high allergy to dust mites were closely related to FEV1 decline. In particular, we have previously identified the impact of the delayed diagnosis on lung function [4], so the early diagnosis of asthma needs to be taken seriously.Funding This study was funded by the Jinan Key Laboratory of Pediatric Respiratory diseases (Xiang Ma is the PI), Clinical Science and Technology Innovation Plan in Jinan (202134067), Clinical Science and Technology Innovation Plan in Jinan ( 202225022), and Shandong Provincial Natural Science Program (ZR2021MH147). The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication. DeclarationsConflict of Interest None.Publisher's Note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Background: The global spread of Corona Virus Disease 2019 (COVID-19) has resulted in a significant disease burden, yet asthma patients do not have the expected high morbidity and mortality rates in the pandemics of COVID-19. Objective:To find the difference of angiotensin-converting enzyme 2 (ACE2) in asthma and non-asthma children and evaluate the effect of inhaled corticosteroids (ICS) on its expression. Methods: The ACE2, immunoglobulin E (IgE) and eosinophils were tested in different children. Results: A total of 157 children aged 3-16 years were enrolled. The expression of ACE2 in asthma children were lower than non-asthma children (T=-2.512, P=0.013). Allergic non-asthma children had a significant higher ACE2 expression than children with allergic asthma (P=0.013) and non-allergic asthma (P=0.029). The expression of ACE2 had no significant difference between first diagnosed asthma children and that had been treated with ICS for≥6 months (F=0.028, P=0.598). The allergic asthma children showed a significantly higher Eosinophils cells (EC) count than the allergic non-asthma (W=200, P＜0.001) and non-allergic non-asthma children (W=1089, P＜0.001). Non-allergic asthma children also had a significant higher EC count than the allergic non-asthma (W=182.5, P＜0.001) and non-allergic non-asthma (W= 200.5, P＜0.001) children. There was no significant difference in IgE levels between asthmatic children and non-asthmatic children (W=2792.5, P= 0.18). Conclusion: Circulating ACE2 levels in asthmatic children were lower than those in non-asthmatic children and ICS treatment for ≥6 months did not affect the expression of ACE2 in peripheral blood in the asthma children.

Background The global spread of coronavirus disease 2019 (COVID‐19) has resulted in a significant disease burden, yet asthma patients do not have the expected high morbidity and mortality rates in the pandemics of COVID‐19. Objective To find the difference of angiotensin‐converting enzyme 2 (ACE2) in asthma and nonasthma children and evaluate the effect of inhaled corticosteroids (ICS) on its expression. Methods The ACE2, immunoglobulin E (IgE), and eosinophils were tested in different children. Results A total of 157 children aged 3–16 years were enrolled. The expression of ACE2 in asthma children were lower than nonasthma children (T = −2.512, p = .013). Allergic nonasthma children had a significant higher ACE2 expression than children with allergic asthma (p = .013) and nonallergic asthma (p = .029). The expression of ACE2 had no significant difference between first‐diagnosed asthma children and that had been treated with ICS for ≥6 months (F = 0.028, p = .598). The allergic asthma children showed a significantly higher eosinophils cells (EC) count than the allergic nonasthma (W = 200, p < .001) and nonallergic nonasthma children (W = 1089, p < .001). Nonallergic asthma children also had a significant higher EC count than the allergic non‐asthma (W = 182.5, p < .001) and nonallergic non‐asthma (W = 200.5, p < .001) children. There was no significant difference in IgE levels between asthmatic children and non‐asthmatic children (W = 2792.5, p = .18). Conclusion Circulating ACE2 levels in asthmatic children were lower than those in non‐asthmatic children and ICS treatment for ≥6 months did not affect the expression of ACE2 in peripheral blood in the asthma children.

BackgroundSince the outbreak of coronavirus disease 2019 (COVID-19), public's awareness of infection prevention and control has increased overall, and various prevention and control measures have been adopted. These measures may also have a certain impact on the occurrence of other infectious diseases. Therefore, we collected information on children with several respiratory infectious diseases in Jinan Children's Hospital in China from 2016 to 2022 and analyzed their changes.MethodWe collected data on age, sex and number of cases of pertussis, measles, scarlet fever, pulmonary tuberculosis, mumps and influenza, which were diagnosed by clinical and laboratory criteria, from 1 January 2016 to 31 December 2022 in Jinan Children's Hospital in Jinan, Shandong Province, China. Data on the number of people affected by these diseases in China from the Chinese Center for Disease Control and Prevention were compared. Then, we processed the data by using WPS Excel 2019 and SPSS.ResultsA total of 12,225 cases were included in this study in Jinan Children's Hospital, which consisted of 3,688 cases of pertussis (2,200 cases before COVID-19 and 1,488 during COVID-19), 680 cases of measles (650 cases before COVID-19 and 30 during COVID-19), 4,688 cases of scarlet fever (4,001 cases before COVID-19 and 687 during COVID-19), 114 cases of tuberculosis (86 cases before COVID-19 and 28 during COVID-19), 449 cases of mumps (340 cases before COVID-19 and 109 during COVID-19) and 2,606 cases of influenza (1,051 cases before COVID-19 and 1,555 during COVID-19). The numbers of children in the hospital with pertussis, measles, scarlet fever, mumps and influenza decreased substantially during COVID-19 in 2020–2022 compared with numbers in 2016–2019, while numbers of patients in China with all six respiratory infectious diseases, including pulmonary tuberculosis, declined during the pandemic. A rebound of pertussis, scarlet fever and influenza was observed in 2021 and 2022.ConclusionsThe study found that viral pathogens such as those causing measles, mumps and influenza all decreased during the pandemic, after which influenza rebounded. Infection diseases caused by bacteria such as scarlet fever and pertussis also decreased during COVID-19, and then a rebound occurred. However, tuberculosis stayed relatively constant.