Epidemiology and Pathogenesis of Otitis Media: Construction of a Phenotype Landscape

Abstract

Otitis media (OM) represents a complex set of clinically defined disease phenotypes. Epidemiological and pathological data suggest that inflammation of the middle ear occurs on a continuum of disease. Here I review epidemiological data and apply mathematical modelling to better define the interrelation of OM phenotypes, including the relationship of upper respiratory tract infection to acute OM (AOM), of AOM to OM with effusion, and of recurrent OM to chronicity of effusion. I use these mathematical models to represent OM graphically as a ‘landscape of disease'. This novel nosology may enable clinicians and researchers to better conceptualise middle ear inflammation in its various forms, although the limits of its application are also discussed.

Acute Otitis Media- An Update

“…US spends $2-3.5 billion per year for treatment of this condition [2,13]. In general it is a disease of childhood, that has a peak incidence of 6-11 months [1,8], 59% of children will have one episode of AOM by age of 2 [1] and 30% will have 2 or more episodes [1], males have a higher …”

“…AOM is related to upper respiratory infection (URTI); in 94% of patient URTI proceeds AOM [1,7], one in three children will develop AOM after URTI [12]. URTI causes nasopharyngitis which affects the Eustachian tube (ET), as a result negative pressure is created and that causes suction of the mucus of the nasopharynx inside the middle ear; that explains why aspirate of AOM can show bacteria like Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis [2,8], which are commensal to nasopharynx [16].…”

“…URTI causes nasopharyngitis which affects the Eustachian tube (ET), as a result negative pressure is created and that causes suction of the mucus of the nasopharynx inside the middle ear; that explains why aspirate of AOM can show bacteria like Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis [2,8], which are commensal to nasopharynx [16]. The initial course of the disease is thought to be viral in origin with bacterial superinfection occurs after that [2,12], many viruses have been implemented as a causative agents which are found in 90 % of AOM cases, like rhinovirus, coronavirus, enterovirus, respiratory syncytial virus (RSV), parainfluenza type 1, 2 or 3, influenza A or B, and adenovirus [1,2,7,14,17]. Among all of these RSV is believed to have the best association with AOM [12].…”

“…Genetics play an important role in the susceptibility of an individual to AOM [1,2,8,12,15]. Native American Maori or Australian Aborigine populations have more prevalence of OM as compared to white population [1].…”

“…Otitis media (OM) has a wide spectrum of diseases that include acute otitis media (AOM), recurrent otitis media (rOM), otitis media with effusion (OME), chronic otitis media with effusion and chronic otitis media [1,2,3]; AOM can be defined as a rapid onset of fever and otalgia [1,2,4], if the child has ≥3 episodes of AOM in the preceding 6 months, or ≥4 episodes in the preceding 12 months then he is considered to have recurrent OM [1,5,6], presence of fluid in the middle ear with absence of signs and symptoms is defined as otitis media with effusion (OME), and if the fluid persisted more than 3 months then it is considered as chronic otitis media with effusion [1], chronic suppurative otitis is defined as discharge with tympanic membrane (TM) perforation for more than 3 months [1]. Patients who have more than 6 episodes in the first 6 years of life are said to be otitis prone [7].…”