Serum Toll-Like Receptor-2 Levels and TLR2 Arg753Gln Polymorphism in Children with Tonsillitis Caused by Staphylococcus aureus and Streptococcus pyogenes

Abstract

     Tonsils play a vital function in the body's immune system in children. Tonsillitis is one of the most common reasons children seek care in hospital ENT departments worldwide. This study examines the relationship between the presence of Staphylococcus aureus and Streptococcus pyogenes isolated from tonsillitis patients, the impact of those bacteria on serum TLR2 levels, and the relationship between the TLR2 Arg753Gln (rs5743708) polymorphism risk and susceptibility to tonsillitis. The study was conceived as a case-control study including 118 participants with tonsillitis colonized with S. aureus and S. pyogenes and 50 uninfected controls. Serum TLR2 levels have been evaluated by utilizing an enzyme-linked immunosorbent assay (ELISA) kit, and TLR2 Arg753Gln polymorphism was detected via ARMS-PCR. Serum TLR2 levels showed a non-significant increase in both the S. aureus and S. pyogenes groups, whereas they increased significantly in tonsillitis children infected with mixed bacteria (P3=0.0018). Moreover, the co-dominant GA genotype and the dominant model GA + AA of TLR2 Arg753Gln polymorphism were significantly elevated in 78% and 84% of tonsillitis patients compared to the control group (46%) (OR = 5.72, 95% CI: 2.30–14.2, P < 0.0001) and (OR = 6.38, P < 0.0001). Bacterial infections led to significantly increased sTLR2 levels in tonsillitis patients in the mixed bacterial group, suggesting that sTLR2 levels might be useful as a diagnostic tool for tonsillitis in children. Additionally, the GA genotype of TLR2 Arg753Gln showed a significant association with the development of tonsillitis and may serve as a prognostic predictor of tonsillitis risk among children.