Otitis media is of course inflammation of the middle ear (the region between the tympanic membrane and the oval window). Most commonly occurs 2º to viral URTI (RSV and rhinovirus are the most common culprits).
Bacterial cause is most commonly strep. pneumoniae.
→ Other notable causative agents are: moraxella catharallis, h. influenzae, s. aureus.
Let’s discuss 3 separate forms of otitis media:
Presents over few days - weeks.
Pathophysiology
It mostly is 2º to viral URTI. Preceding viral infection can disturb the normal microbiota of the ear and allow bacteria to lead infection via our Eustachian tube.
Bacterial cause is most commonly strep. pneumoniae, moraxella catharallis, h. influenzae, s. aureus.
🏘 Epidemiology
It is most common in young children due to a shorter, straighter, wider Eustachian tube.
About 2/3rds of children will have AOM.
😷 Presentation
- ⭐️ Otalgia is the most common cause
- ⭐️ Tugging or pulling on the ear is commonly seen in kids as there tympanic membrane is stretched.
- Fever - present in about half the cases.
- Hearing loss
- Discharge - if the tympanic membrane perforates due to excessive stretching.
→ ⭐️ The tympanic membrane may be red and bulging outwards.
→ There may be a perforation in the membrane with discharge.
🔍 Investigations
- 🏆 Clinical diagnosis.
- Discharge should be sent for MC&S.
- If the patient has signs of sepsis → blood cultures.
🧰 Management
Typically is self-limiting within 1-3 days, and we shouldn’t do anything but advise simple analgesia for the pain. Otigo drops (lidocaine) may also be used.
We give antibiotics such as:
Amoxicillin (or erythromycin/clarithromycin if allergic to penicillin) - for 5-7 days.
- It is indicated in the case of:
- Symptoms persisting >4 days.
- Systemically unwell patient.
- Immunocompromised
- Younger than 2 years old with bilateral AOM.
- Perforation and/or discharge present. If the eardrum perforates, patients should keep it dry for 6 weeks.
🚨 Complications
- Mastoiditis - mastoiditis is a very serious condition as it can lead to meningitis. The density of the bone behind the ear is thinnest and this is swollen in this region as opposed to the denser mastoid process. The pinna may be pushed down and forward and hearing may be affecting. If present, hospital admission is indicated.
- Facial nerve paralysis
- Brain abscess
This is also known as glue ear. It is common in children. It is ultimately an accumulation of viscous inflammatory fluid within the middle ear that can then lead to conductive hearing loss (as the middle ear is usually filled with air).
Pathophysiology
It occurs as the result of chronic ear infections and Eustachian tube dysfunction. It commonly occurs after AOM.
This is because the Eustachian tube is unable to remove any of this collection and so it just builds up.
⚠️ Risk factors
- Bottle fed babies - as they often lie down and drink so the milk can enter the nasopharyngeal and then Eustachian tube and irritate it.
- Parental smoking
- Atopy - genetic tendency to develop allergies such as allergic rhinitis or atopic dermatitis.
- Mucociliary and craniofacial disorders - such as cystic fibrosis and Down’s syndrome.
😷 Presentation
- Conductive hearing loss - the most typical presentation.
On examination:
- Dull grey tympanic membrane
- Lack of light reflex
- Bubble trapped behind the tympanic membrane
- Aural fullness - as the middle ear is filled with fluid.
🔍 Investigations
It is mainly clinical diagnosis.
🏆 Pneumatic otoscopy (or tympanometry) should be used to make the diagnosis in a child with symptoms or signs suggestive of OME according to NICE.
Nasal endoscopy looking for post-nasal masses obstructing the Eustachian tube.
🧰 Management
Most cases resolve within 3 months, therefore, we manage it through surveillance.
If it persists >3 months we can manage it with:
- Hearing aid insertion
- Autoinflation
- Myringotomy and grommet insertion.
- Adenoidectomy
There are 2 types:
- Chronic suppurative otitis media
- Chronic squamous otitis media
🏘 Epidemiology
It’s seen in 1% of children and 0.5% of adults. 50% of these patients have hearing problems.
Pathophysiology
CSOM is due to tympanic membrane perforation and subsequent inflammation of the middle ear.
It is most commonly due to recurrent episodes of AOM, but may also be due to a severely perforated tympanic membrane, grommets, craniofacial abnormalities.
😷 Presentation
- Patients tend to have recurrent AOM, previous ear surgery or trauma to the ear.
- ⭐️ Chronic ear discharge (>6 weeks)without fever or otalgia.
- ⭐️ Conductive hearing loss
On examination:
- Perforated tympanic membrane
🔍 Investigations
🏆 Once again it is a clinical diagnosis.
If a cholesteatoma is suspected (accumulation of squamous epithelium and keratin debris in the middle ear and mastoid), a temporal bone CT may be done.
🧰 Management
- Aural toileting - cleaning the external ear.
- Topical antibiotics/steroids until symptoms resolve/reduce.
- Myringoplasty - to close the perforation.
- Tympanoplasty - myringoplasty + reconstruction of the ossicular chain.