Otitis Externa Flashcards
What is Otitis externa?
Inf of external ear
What groups of people is Otitis externa more prevalent in? (2 things)
- Young age
- Females
What is the pathophysiology of Otitis Externa? (5 steps)
- Disruption to EAC protective mechanisms
- Pathogen overgrowth / inflamm
- Skin –> erythematous / swollen / tender / warm
- Debris + discharge accum –> canal narrowing
- Further entrapment of pathogens
What can lead to Disruption to EAC protective mechanisms? (3 steps)
- Repeated water exposure (interrupts wax formation)
- Trauma to canal (cotton buds)
- Blockage (debris)
What are the most common causative pathogens of OE? (3 things)
- Pseudomonas aeruginosa (40%)
- S. epidermidis
- S. aureus
What are the RF for OE? (7 things)
- Freq water contact (e.g swimmers / freq hair washers)
- Humid environments
- Ear polyps / foreign bodies
- Narrow ear canals
- Ear eczema / Psoriasis
- Trauma (hearing aids / cotton buds)
- Immunocompromised / DM (inf risk)
What are the RF for OE? (7 things)
- Freq water contact (e.g swimmers / freq hair washers)
- Humid environments
- Ear polyps / foreign bodies
- Narrow ear canals
- Ear eczema / Psoriasis
- Trauma (hearing aids / cotton buds)
- Immunocompromised / DM (inf risk)
What is the classical clinical picture of OE?
Progressive ear pain + purulent discharge
What are the CF of OE? (4 things)
- Pain
- Discharge
- Itchiness
- Conductive Hearing Loss (if ear blocked)
What are the CF of OE? (4 things)
- Pain
- Discharge
- Itchiness
- Conductive Hearing Loss (if ear blocked)
What will you see @ exam of OE? (4 things)
- Erythema / swelling
- Pus / discharge
- Tenderness
- Lymphadenopathy in neck / around ear
What does White / yellow Pus indicate?
Bac inf
What does Thick white grey w spores Pus indicate?
Fungal inf
What does Clear grey Pus indicate?
Otitis media
What are some DDx that present similarly to OE? (3 things)
- Otitis media w Perforation
- Ramsay Hunt syndrome
- Furuncle
How is OM w Perforation different to OE? (3 things)
- Clear / bloody discharge
- Pain relieved after discharge
- Tympanic memb inflamm + Perforated
How is Ramsay Hunt syndrome different to OE?
Vesicular rash within 2 days of first onset of pain
How is Furuncle different to OE?
Visible bulge present @ otoscope exam
How is the Dx of OE made?
Clinical Dx (based on thorough Hx + otoscopy)
When should you do further investigations for OE? (4 things)
- Not responding to Abx
- Signs of fungal disease @ otoscopy
- Recurrent disease
- Complicated disease
What further investigations can you do for OE? (3 things)
- Swabs of discharge –> send for culture
- Glucose levels for DM (in recurrent disease)
- High Res CT scan (HRCT) (for complicated disease)
What is the main things in Mx of OE? (4 things)
- Prevention
- Aural toileting
- Topical abx
- Simple analgesia
What Topical abx is sued for OE?
No single regime has been found to be the best
Therefore what does Abx choice depend on for OE? (3 things)
- Pt / doctor preference
- Local sensitivities
- Side fx
What can you give to decrease swelling of Canal + reduce pain?
Steroid drops
What are the Prevention options for OE? (4 things)
- Remove debris by Microsuction
- Avoid swimming + cotton buds
- Use Bone-achored hearing aid (BAHA) (if dey need a hearing aid)
- TUC (eczema / polyps)
What are the complications of OE? (4 things)
- Malignant OE
- Mastoiditis
- Osteomyelitis
- Intracranial spread
What is Malignant OE?
Spread of OE into Mastoid + Temporal bones
Who does Malignant OE typically occur in? (2 things)
- Elderly DM pt
- Immunocompromised pt
What are the CF of Malignant OE? (2 things)
- Severe pain
- Headaches
What investigation should you do for sus Malignant OE?
Urgent CT scan
What neurological involvement could Malignant OE cause?
CN 7 involvement
What is the Mx for Malignant OE?
IV abx (for debridement)
