Genetic susceptibility has a major role in the pathogenesis of acute otitis media (AOM). In the present study, we investigated the variability of 5 cytokine genotypes as related to susceptibility and outcome of AOM in early infancy.
Single nucleotide polymorphisms in IL-6 (–174 G→C), IL-10 (–592 C→A, –819 C→T and –1082 G→A), TNF-α (–308 G→A), IFN-γ (+874 A→T) and TGF-β1 (codon 10 C→T; codon 25 G→C) genes were investigated and related to clinical course and outcome in 96 infants younger than 9 months with AOM.
Compared with wild genotypes, IL-10 (–592, –819 and –1082) and TGF-β1 (codon 10) genotypes carrying the alternative allele were related to more AOM episodes (P < 0.0001, P < 0.0001, P < 0.0001 and P = 0.002, respectively) and the need for tympanostomy tubes. Furthermore, IL-10 (–1082) and TGF-β1 (codon 10) genotypes carrying the alternative allele were related to later onset of first AOM episode than wild-type genotypes (P = 0.007 and P = 0.039, respectively). No relationship was found about AOM complications.
Our findings suggest that IL-10 and TGF-β1 genotypes are related to the age of AOM onset, multiple AOM episodes and insertion of tympanostomy tubes, pointing to the involvement of anti-inflammatory cytokines in AOM during infancy.