Otitis Media

a.  Acute otitis media (AOM)

·   Defined as infection or inflammation of the middle ear

·   Any entity causing Eustachian tube dysfunction (allergies, etc.) can predispose to infection (negative pressure causes effusions, which can become infected)

·   Much more common in children than adults

·   Bacterial pathogens: Strep  pneumo and H. Flu most common; group A strep, staph aureus, and moraxella are less frequent causes

·   Viral pathogens: RSV, influenza viruses, and rhinoviruses (most of the data is in kids)

·   Amoxicillin (500mg po q8-12 hr x10 days) is generally adequate for empiric tx of community-acquired otitis media; there are some beta-lactam resistant strains of Moraxella and H. flu,  should respond to Augmentin

b.  Otitis media with effusion (OME)

·   Defined as a fluid collection within the middle ear space (may occur without infection due to barotrauma, allergies etc.)

·   Often leads to conductive hearing loss and risk for TM rupture

·   On otoscopic exam, the TM is retracted and there is clear to yellowish fluid behind the TM (may see bubbles)

·   If there are symptoms of ear fullness or hearing loss, pts should be referred for tympanometry with audiometry to assess the degree of conductive hearing loss. If sensorineural hearing loss is demonstrated, this warrents immediate ENT referral

c.   Otitis externa:

·   Inflammation of the external auditory canal (can be allergic or infectious)

·   Tends to occur in people with water exposure to the ear (swimmers) or in persons with hearing aids, trauma/excessive q-tip use

·   Clinically presents as otalgia, pruritus, discharge, and hearing loss.  Pain with tragal pressure or when the auricle is pulled superiorly

·   Most common organisms are staph aureus and pseudomonas

·   If the infection is limited to the external auditory canal, treatment with topical abx and anti-inflammatory agents is appropriate (ie. ciprodex gtts)

·   Complications include necrotizing otitis externa; any pts with external otitis with DM, immunodeficiency or clinical evidence of extension beyond the ear should be treated with po or IV abx (see below)

d.  Malignant or necrotizing otitis externa

·   defined as an invasive infection of the external auditory canal with progression to the soft tissue, cartilage, and bone of the temporal region and skull base.

·   typically occurs in older, diabetic pts; also can occur in HIV + pts. Rarely occurs in children.

·   Clinically presents as protracted, deep ear pain (otalgia) that is out of proportion to PE findings, also with significant otorrhea

·   As the infection progresses, osteomyelitis of the base of the skull and temporomandibular joint can occur, with associated CN palsies

·   Pseudomonas aeruginosa is nearly always the pathogenic organism (other rare causes include candida, aspergillus, staph and other gnr)

·   Oral (or IV) antipseudomonal abx are the mainstay of treatment (some increasingly quinolone resitant strains)

e.   Acute mastoiditis

·   Progression of infection or inflammation from AOM to the mastoid air cells (in the petrous bone, just superior to the middle ear)

·   Clinically presents as a tender, red swelling posterior to the ear; can occur in any age group, but most severe in the elderly

·   Can lead to dissolution of the surrounding bone and CNS extension if the pus is not evacuated

(Victoria Kelly MD, 12/20/10)