To further understand the role of gene single nucleotide polymorphism (SNP) in the occurrence of type 2 inflammation-related asthma in children by analyzing the gene single nucleotide polymorphism (SNP), lung function and type 2 inflammation indicators of children diagnosed with asthma in outpatient and inpatient. To provide a theoretical basis for the study of personalized treatment and prevention strategies for asthma.

Type of study:

This was a prospective, randomized case-control design.To investigate the role of genetic single nucleotide polymorphisms (SNPs) in children with type 2 asthma, and the effects of SNPs on type 2 inflammatory markers and pulmonary function indicators.

Methods:

Children with asthma who were treated at our pediatric respiratory specialty clinic and who met the criteria for type 2 inflammation were included in the case group (Type 2 inflammation was considered to be present if any of the following conditions were present: Fraction of exhaled nitric oxide(FeNO)≥20ppb；Blood eosinophilcount≥350/ul；Percentage of sputum eosinophils>3%; Asthma is caused by inhaled allergens.). The control group is healthy children who underwent physical examination. To compare the differences of single nucleotide polymorphisms (SNPs) between children with type 2 asthma and healthy children, and to explore the risk factors of type 2 asthma.

The differences of indicators between different genotypes were compared, including type 2 inflammation indicators (including Fraction of exhaled nitric oxide(FeNO)、Blood eosinophil count、Percentage of sputum eosinophils and Serum total immunoglobulin E) and pulmonary function indicators(Forced expiratory volume in one second(FEV1)、Forced vital capacity(FVC)、Ratio of forced expiratory volume in one second to forced vital capacity(FEV1/FVC) and Peak expiratory flow(PEF)).

Inclusion Criteria:

1. All children with asthma diagnosis accord with the GINA in 2023 edition;
2. Other diseases that could cause wheezing and cough were excluded, such as acute laryngitis, diphtheria, congenital airway abnormalities, and tracheal foreign bodies;
3. In front of the hospital 2 weeks without antibiotics, systemic hormone medication history;
4. There were no other complications, such as congenital heart disease, pneumonia, gastroesophageal reflux disease, muscle dysplasia, etc.

Exclusion Criteria:

1. Children who had taken immunosuppressants, antibiotics and other drugs for a long time before admission;
2. Children with primary immunodeficiency disease;
3. The children and their families failed to cooperate or refused the experimental observation.

There was no significant difference in the ratio of male to female between the case and control groups

Children with asthma, aged 3-14 years, attending our hospital.