EENT Infections - Hunter Flashcards
What is otitis externa?
An infection of the external auditory canal.
What is a common nickname for otitis externa and why?
It is called swimmer’s ear because it is most common in swimmers and divers who frequently get water trapped in the external canal.
What are the predisposing factors for otitis externa?
- high environmental temperatures
- trauma from mechanical removal of cerumen
- follows insertion of foreign objects in canal
- associated with chronic dermatologic disease such as eczema
What organisms are the most common causes of otitis externa?
Gram-negative bacilli.
What specific organism is the major pathogen associated with otitis externa?
Pseudomonas aeruginosa
Pseudomonas aeruginosa is the most common cause of what?
- otitis externa/swimmer’s ear
2. malignant otitis externa
What is another organism that causes otitis externa?
Staphylococcus aureus. Although it is a less common cause than Pseudomonas.
Describe a typical presentation of otitis externa.
May present with ear pain, itching and discharge with a swollen and erythematous external canal. Fever is usually lower than 38.3 degrees C and the pinna may be tender. It may also be painful to chew for many patients.
What is standard treatment for otitis externa of bacterial origin?
- dicloxacillin or ciprofloxacin
2. less severe cases use ofloxacin ear drops
What findings are more associated with malignant otitis externa than with otitis externa?
- a temperature greater than greater than 38.3 degrees C
- severe pain associated with ear canal and surrounding areas
- presence of a purulent exudate
How does malignant otitis externa usually start?
Often begins as infection of external auditory meatus - often with otorrhea. Especially in immunocompromised adults with diabetes.
Why is malignant otitis externa so dangerous?
Necrotizing infection can spread to the cartilage, bone (mastoid process), blood vessels and brain. Can be fatal if untreated.
What is the treatment for malignant otitis externa?
- Imepenem
2. referral to otolaryngologist for surgical debridement
What is otitis media?
Bacterial infection of the inner ear mucosa with exudate production.
Otitis media is especially associated with what population?
Children. 50% experience an episode before age 1 and 80% by age 3.
What is the most frequent diagnosis in febrile children?
Acute Otitis media.
Does otitis media affect boys more often than girls?
yes.
Otitis media often presents with what other two conditions?
- purulent conjunctivitis
2. rhinosinusitis
What population is especially at risk for recurrent otitis media?
Persons with immune deficiencies.
What microorganism is the most common cause of acute otitis media?
Streptococcus pneumoniae
What are some other types of microorganisms that are common causes of acute otitis media?
- Streptococcus pneumoniae
- nontypeable Haemophilus influenzae
- Moraxella catarrhalis
What are some other less common causes of acute otitis media?
- Staphyloccus aureus
2. Streptococcus pyogenes
What is the most common cause of acute otitis media in babies younger than 6 weeks of age?
Gram-negative bacilli such as E. coli, Klebsiella pneumonia and pseudomonas aeruginosa.
Acute otitis media is often preceded by what
Upper respiratory tract viral infection.