Acute otitis externa in children, Emergency Department

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Definition
  • Inflammation of the skin of the External Auditory Meatus
  • Can be localised (confined to meatus) or generalised (involves other areas of skin)
  • Can be acute (less than 6 weeks duration) or chronic
  • Affects 10% of the population at some point, however in children acute otitis media is much more common, with or without a secondary otitis externa.
Pathology
  • Infective: 
    1. Bacterial – Pseudomonas Aeruginosa, Staph. Aureus and proteus commonest
    2. Fungal – Aspergillus, candida (often after previous use if ear drops) 
    3. Viral – Herpes Simplex and zoster
  • Reactive: 
    Often seen in patients with eczema, psoriasis, seborrhoeic dermatitis
Symptoms and history
  • Presents with itching, discharge, hearing loss and pain, which may be severe.
  • Look for symptoms of head and neck infection elsewhere e.g. tonsillitis/sinusitis
  • Predisposing factors include humidity, swimming, hearing aids, trauma, eczema/psoriasis, narrow ear canals (e.g Downs Syndrome), Diabetes Mellitus
  • Ask about previous otological history and identify any possible allergens/irritants
  • Important to determine if any preceding symptoms of acute otitis media
Examination findings
  • External canal may be erythematous, narrow, oedematous, and tender.
  • It may be impossible to visualise the tympanic membrane.
  • Discharge – green/offensive may suggest pseudomonas, mucoid may suggest middle ear pathology, or fungal hyphae may be present.
  • May be pain on moving pinna and tragal tenderness.
  • There may be post-auricular tenderness localised to a palpable lymph node.
  • The presence of a perforation suggests the primary pathology may be in the middle ear.
  • Look for any evidence of spreading cellulites/erysipelas.

Beware bony tenderness over the mastoid, with fluctuance and displacement of the pinna down and forwards suggest mastoiditis.

Differential diagnosis
  • Otitis externa
  • Otitis Media and otitis externa
  • Otitis Media with perforation (unable to see tympanic membrane)
  • Consider foreign body with secondary infection Investigation
  • Get an ear swab for microbiology if recurrent infection or failure of a prior treatment.
Management
  • Analgesia.
  • Topical antibiotic/steroid drops. Gentisone HC is the departmental choice. Clotrimizole drops used for fungal infections. No evidence of benefit with oral antibiotics in uncomplicated acute otitis externa.
  • If patient returns after treatment with Gentisone HC with same problem, swab ear and arrange ENT review.
  • If you are uncertain if TM perforation present – safe to use topical aminoglycosides for up to 2 weeks in a patient with a discharging ear and a perforation of the tympanic membrane.
  • If canal very swollen and instillation of drops not possible – consider referral to ENT for wick insertion. Suction clearance may also be of benefit if copious debris in canal.
  • If evidence of spreading facial cellulites/erysipelas then refer to ENT for consideration of admission and intravenous antibiotics.
  • Early reassessment desirable – can be by GP or arrange ENT review if recurrent infection or failure of a prior treatment.
Discharge advice
  • Regular analgesia – pain may be severe
  • Advice on the correct instillation technique of drops – lie head on pillow with ear facing upwards, insert drops, massage the tragus, then lie in the same position for 5-10 minutes before moving.
  • Advice to keep ear dry
  • Treatment should be continued for about 1 week after resolution.
References
  1. Key topic in Otolaryngology 2nd Edition, NJ Roland et al, Published by Taylor & Francis
  2. Otitis Externa Clinical Otolaryngology, 32, 457-459, McKean SA, & Hussain SSM
  3. Diagnosis and Management of Otalgia in Children, Arch. Dis. Child. Ed. Pract. 2009; 94; 33-36, Majumdar S et al
  4. BMJ Clinical Evidence, BMJ Publishing Group, BMJ Clinical Evidence 2008;06:510, Hajioff D, and MacKeith S
  5. Antimicrobial Prescribing for Otitis Externa in Children, The Paediatric Infectious Disease Journal, Vol. 23, No. 2, February 2004, SI McCoy et al
  6. Evidence review and ENT-UK consensus report for the use of aminoglycosidecontaining ear drops in the presence of an open middle ear. Clin Otolaryngology 2007 Oct;32(5):330-6. Phillips JS, Yung MW, Burton MJ, Swan IR.
Editorial Information

Last reviewed: 24 February 2017

Next review: 13 November 2019

Author(s): Steve Foster

Approved By: Paediatric Clinical Effectiveness & Risk Committee

Reviewer Name(s): Steve Foster