Acute suppurative otitis media
ASOM is most common in children between the ages of 3 to 7 years. Such infants have a short, wide, more horizonally placed eustachian tube than adults, allowing contamination from the regurgitation of feed. Poor sanitation, over-crowding and malnutrition are all risk factors in children. Risk factors in all age groups include recurrent or chronic rhinosinusitis, chest disease and eustachian tube dysfunction. Causes of eustachian tube dysfunction include hypertrophy of the adenoids, cleft palate and submucous cleft palate.
ASOM is a bacterial disease caused by pus forming organisms. Pathogenic bacteria have been isolated from the nasopharynx in up to 97% of children with ASOM. The bacterial infection may be a primary infection, or secondary following a viral acute non-suppurative otitis media. Bacteria enter the middle ear cleft via the eustachian tube, a tympanic membrane perforation or are blood-borne. Common organisms include:
- Deafness - a conductive hearing loss which progresses
- Pain - due to accumulation of pus and pressure necrosis of the tympanic membrane
- Otorrhoea - occurs after episodes of pain, and is due to perforation of the tympanic membrane and release of pus
- Pyrexia - children are typically fretful with a high (>39 degrees c) pyrexia
- Tympanic membrane - is initially dull, then becomes hyperaemic. Evenually becomes full, angry and red, and finally perforates if unresolved
- Rest in a warm and well humidified room.
- Antibiotics may be given. Some would give prophylactically to prevent the risk of perforation. Others would given only in the presence of uncontrolled pyrexia. Amoxicillin will cover most pathogenic organisms. However, up to 14% of cases have beta-lactamase resistance, and co-amoxiclav is recommended. There is some evidence that antibiotic use may increase the risk of recurrence.
- Decongestants have a traditional role to play, although they have not been proven to be of significant value.
- Predisposing conditions to ASOM should be treated after resolution.
- Acute mastoiditis - mucositis may progress to an osteomyelitis
- Gradenigo's syndrome - petrositis causing ASOM, an ipsilateral abducent nerve palsy and pain over the distribution of the trigeminal nerve
- Citelli's abscess - spread from the media mastoid air cells into the digastric fossa
- Bezold's abscess - spread alond the inferior boarder of sternomastoid
- Extradural abscess
- Subdural abscess
- Lateral sinus thrombosis
- Otitic hydrocephalus
- Facial nerve palsy
- Non-suppurative middle ear effusion - persists for over 30 days in 40% of children
- High tone sensorineural hearing loss - due to the action of bacterial toxins migrating across the round window
- Tympanic membrane perforation
- Middle ear adhesions
- Erosion of the ossicular chain
- "Revisiting the 2004 AOM Management Guidelines" from Medscape (USA).