INTRODUCTION – AGENTS
The majority of otitis media (OM) infections are caused by organisms commonly found in the upper aerodigestive tract, including the ears, nose, sinuses, oral cavity, oropharynx, hypopharynx, and larynx. These agents include Streptococcus pneumoniae, Haemophilus influenzae, and less commonly, Moraxella catarrhalis, Streptococcus pyogenes, and Staphylococcus aureus. Anaerobic bacteria may play a role in OM in the neonatal period. Viruses that infect the upper respiratory tract also frequently cause OM.
Young children compromise the majority of cases of OM. Children with craniofacial syndromes or trisomy 21 (Down syndrome) may be particularly prone to OM. Children with a cleft palate or submucous cleft palate are at high risk for persistent or recurrent acute OM.
Some adults also may be predisposed to OM, including those with HIV and concomitant adenoid hypertrophy that obstructs the eustachian tube orifice, as well as recipients of head and neck radiation. Additionally, certain ethnic groups, including Native Americans, have a higher incidence of OM. An otherwise healthy adult with persistent unilateral OM warrants additional work-up for a possible underlying malignancy.
Acute OM is one of the most frequently encountered otologic infections in children (Table 5.1). Young children may be inconsolable and will sometimes tug or pull on the affected ear, though this sign is very nonspecific in children under 2. They will often complain of pain or otalgia as a prominent symptom.