Immunologic dysfunction contributes to the otitis prone condition

Abstract

Acute Otitis Media (AOM) is a multifactorial disease occurring mostly in young children who are immunologically naïve to AOM pathogens. This review focuses on work from Rochester NY, USA over the past 12 years among young children who had AOM infections microbiologically-confirmed by tympanocentesis, so called "stringently-defined". Among stringently-defined otitis prone children deficiencies in fundamental immune defense mechanisms have been identified that contribute to the propensity of young children to experience recurrent AOM. Dysfunction in innate immune responses that cause an immunopathological impact in the nasopharynx have been discovered including inadequate proinflammatory cytokine response and poor epithelial cell repair. Adaptive immunity defects in B cell function and immunologic memory resulting in low levels of antibody to otopathogen-specific antigens allows repeated infections. CD4+ and CD8+ T cell function and memory defects significantly contribute. The immune profile of an otitis prone child resembles that of a neonate through the first year of life. Immunologic deficits in otitis prone children cause them to be unusually vulnerable to viral upper respiratory infections and respond inadequately to routine pediatric vaccines.

Keywords: Acute otitis media; Adaptive immunity; Antibody; Antigen presenting cells; B cells; CD4+ T cells; Haemophilus influenzae; Innate immunity; Moraxella catarrhalis; Otitis prone; Streptococcus pneumoniae.

Figure 1.. Nasopharynx and middle ear responses in sOP versus NOP children.

Relative levels that show a statistical difference between sOP versus NOP children are depicted with up or down arrows. Modulator measurements are of proteins except those in brackets are of mRNA.

Figure 2.. PBMC and serum immune responses in sOP versus NOP children.

Relative levels that show a statistical difference between sOP versus NOP children are depicted with up or down arrows. Modulator measurements are of proteins except those in brackets are of mRNA.