Egypt J Pediatr Allergy Immunol, (April 2023), Volume No. 21, Issue 01  
Egypt J Pediatr Allergy Immunol 2023 ; 21 ( 01 ) : -
, ESP - 351  
IL 13rs20541 single nucleotide polymorphism and serum IL -13 level in children with bronchial asthma
Mona Adel Khattab   Mahitab Morsy Hussein   Walaa Shawky Khater        
Background: Bronchial asthma is a common respiratory illness affecting adult and pediatric populations. Interleukin (IL)-13 is a central key mediator of allergic inflammation, and it plays a pivotal role in the pathogenesis of asthma. Several studies revealed that genetic variants of IL-13 promoter rs1800925 allele play a role in asthma severity. We sought to investigate the role of IL-13 rs20541 single nucleotide polymorphism (SNP) and serum IL -13 level in relation to asthma severity in a group of asthmatic children . Methods: This controlled cross-sectional study included 80 participants: 40 apparently healthy controls and 40 asthmatic children, subdivided into three groups: mild (n=12), moderate (n=18 cases), and severe (n=10), recruited from Pulmonology Unit, Children’s Hospital, Ain shams university. Characterization of IL-13 rs20541 SNP was achieved by TaqMan real-time PCR. Serum IL-13 concentration was measured using a commercial sandwich ELISA assay. Results: The dominant genotype as regards IL-13 rs20541 SNP among patients and controls was GA (60% and 92.5%, respectively). G and A allele frequencies between patients and controls differed significantly (p =0.002) as the dominant allele in the control group was G allele (70.0%), versus the A allele in the patients’ group (53.8%). Patients had statistically significantly higher levels of IL-13 compared to controls (median= 45 pg/ml versus 4 pg/ml; p<0.001) Serum IL-13 correlated positively with IgE levels and was able to discriminate between patients with severe asthma and those with mild to moderate asthma at cut off value of >83 pg/ml (sensitivity 90%, specificity 90%, positive predictive value 96.4% and negative predictive value 75%). Conclusion: IL-13 rs20541 SNP polymorphism is associated with asthma in Egyptian children, while serum IL-13 is linked to the severity of asthma.