HEENT 12: Otitis Externa Flashcards
What is acute otitis externa and the causative organisms?
< 3 weeks, bacterial
- Pseudomonas aeruginosa (20-60%)
- Staphylococcus aureus (10-70%)
- others – Klebsiella, Proteus (2-3%)
What is chronic otitis externa and the causative organisms?
≥ 3 months, fungal or dermatological conditions
- otomycosis (fungal ear infection)
- Aspergillus or Candida albicans
Fungal Otitis Externa
- may follow overuse of antibiotic ear drops
- itching, slight pain
- black fine exudate (Aspergillus niger)
- white brown gelatinous film (Candida)
Viral Otitis Externa
- caused by Herpes simplex, zoster, or measles
- pain, blister, swelling
- requires treatment of underlying cause (ie. antivirals)
Malignant Otitis Externa
- caused by P. aeruginosa
- infection spread to cartilage and temporal bone (osteomyelitis)
- rare – elderly with poorly controlled diabetes and immuncompromised
- urgent referral and systemic antibiotics required
What are the risk factors for otitis externa? (7)
- 7-12 years old (rates decline after age 50)
- prolonged exposure to water (swim/bath) → skin maceration and increased pH
- high temperature or humidity
- absence of cerumen
- trauma
- use of objects that occlude auditory canal
- dermatological conditions
What are the signs and symptoms of otitis externa? (7)
- mild to severe pain (otalgia) – exacerbated by movement of ear lobe or tragus, acute onset, unilateral
- itching/pruritus
- ear fullness
- headache
- discharge (otorrhea)
- swollen ear canal
- loss of hearing
When is referral required? (5)
- fever, malaise, bleeding, discharge, progressing ear pain, hearing loss
- diabetes or immunocompromised
- history of radiation
- tympanostomy tubes
- suspected perforated tympanic membrane
Bacterial
What is the treatment for bacterial otitis externa?
topical treatment
- acidifying agents +/- corticosteroids
- topical antibiotics +/- corticosteroids
Bacterial
When is systemic treatment required? (3)
- increased risk of infection – diabetes, immunocompromised)
- infection spread beyond external area
- concurrent otitis media
Bacterial
Acidifying Agents
- vinegar/water mixture
- can use as prophylaxis
- do not use if tympanic membrane ruptured
Bacterial
Antibiotics (OTC)
- polysporin ear/eye drops x 10 days – gramicidin, polymyxin B
- polysporin plus pain relief ear drops x 7 days – polymyxin B, lidocaine HCl
Bacterial
Antibiotics (Rx)
- FQs: ciprofloxacin, moxifloxacin, ofloxacin
- AGs: tobramycin
- combos with CS: ciprofloxacin/dexamethasone (ciprodex), framycetin/gramicidin/dexamethasone (sofracort), tobramycin/dexamethasone (tobradex)
- duration: 7-10 days
Bacterial
What is the treatment for mild otitis externa?
- acetic acid
- OTC topical antibiotic (polysporin)
Bacterial
What is the treatment for moderate or longer duration otitis externa?
- combination of topical antibiotic with steroid – preferred
- OTC topical antibiotic (polysporin)
Fungal
What is the treatment for fungal otitis externa?
- acidifying agents
- antifungals
Fungal
Antifungals
- clotrimazole 1% solution (compounded)
- locacorten – vioform (clioquinol/flumethasone pivalate)
When should patients see improvement?
within 24 hr
