Otitis Externa Flashcards
What is Otitis Externa?
- This is the inflammation of the skin in the external ear canal
What determines the difference between acute otitis externa and chronic otitis externa?
- Acute <3 weeks
- Chronic >3 weeks
What is another name for Otitis Externa?
- Swimmer’s Ear
What are predisposing factors for Otitis Externa?
- Exposure to water
- Trauma in the ear canal
What is protective against Otitis Externa?
- Ear Wax
What are some of the causes of Otitis Externa?
- Bacterial Infection
- Fungal Infection (aspergillus/ candida) - multiple courses of topical antibiotics. Antibiotics kill off the friendly bacteria which have a protective effect against fungal infections
- Eczema
- Seborrhoeic Dermatitis
- Contact Dermatitis
What are the bacterial causes of Otitis Externa?
- Pseudomonas Aeruginosa
- Staphylococcus Aureus
What is important to know about Pseudomonas Aeruginosa ?
- Gram-negative aerobic rod shaped bacteria
- Can colonise the lungs in patients with cystic fibrosis
- naturally resistant to many antibiotics and can be treated with gentamicin/ ciprofloxacin
How does Otitis Externa Present?
- Ear Pain
- Discharge
- Itchiness
- Conductive Hearing Loss
What would be seen on examination for Otitis Externa?
- Erythema/ Swelling of the ear canal
- Tenderness of the ear canal
- Pus/ Discharge in the ear canal
- Lymphadenopathy
How can Otitis Externa be diagnosed ?
- Otoscopy
- Ear Swab (to determine causative organism)
What is the managment of mild Otitis Externa?
- Acetic Acid 2% (anti fungal and antibacterial effect)
- can be used prophylactically before and after swimming in patients who are prone to otitis Externa
What is Malignant Otitis Media?
- This is an uncommon type of Otitis Externa that is found in immunocompromised individuals (diabetic patients)
What is the common causative organism in Malignant Otitis Externa?
- Pseudomonas Aeruginosa
What is the Pathophysiology of Malignant Otitis Externa?
- Infection occurs in the external auditory meatus in the soft tissue
- This progresses to involve the soft tissues into the bony ear canal
- Progresses to temporal bone osteomyelitis
What are the key features in the history of malignant Otitis Externa?
- Diabetes/ Immunosuppression
- Severe/ unrelenting/ Deep-seated Otalgia
- Temporal Headaches
- Purulent Otorrhea
- Possibly dysphasia, hoarseness, or facial nerve dysfunction
What investigations can be done for Otitis Externa?
- CT scan
What is the treatment for Malignant Otitis Externa?
- ENT Admission
- IV Antibiotics
- Imaging ( CT/ MRI) to assess the extent of the infection
When should there be a referral to ENT?
- non-resolving otitis Externa with worsening pain
What is the treatment for moderate Otitis Externa?
- topical antibiotic and steroid: (neomycin, dexamethasone and acetic acid), (neomycin and betamethasone), (gentamicin and hydrocortisone), (ciprofloxacin and dexamethasone)
What are the side effects of Aminoglycosides?
- Potentially Ototoxic if they are able to get past the tympanic membrane
- It is essential to exclude a perforated tympanic membrane before using topical aminoglycosides in the ear
- Refer a patient for Micro-suction of the debris from the canal to help visualise the tympanic membrane
- ## Refer the patient if the canal is so blocked/ swollen and topical treatments cannot reach the site of infection
What is the treatment for severe Otitis Externa?
- oral antibiotics
- discussion for ENT admission with IV antibiotics
- Ear Wick - used in the canal when it is very swollen and treatment with ear drops or sprays may be difficult ( contains topical treatments for otitis Externa - antibiotics and steroids)
- Wicks are inserted into the ear canal and left there for a period of time
- As the swelling and inflammation settle, the ear wick can be removed and treatment can continue with drops or sprays
What is the treatment for fungal Infection of the ear?
- Clotrimazole
What are the complications of malignant otitis Externa?
- Facial nerve damage and palsy
- Other cranial involvement (glossopharyngeal, vagus or accessory nerves)
-Meningitis - Intracranial thrombosis
- Death
