PANCE Blueprint EENT (7%)

Otitis externa

Patient will present as → a 4-year-old girl who is brought to the clinic by her mother, who states that the child has been complaining of progressively worsening ear pain and itchiness over the past week. Examination reveals left tragal tenderness and an edematous and closed canal. Weber lateralizes to the left.

Otitis externa (aka swimmer's ear) is an infection of the external auditory canal secondary to trauma or a consistently moist environment, which favors the growth of fungi or bacteria

  • It generally presents with canal itching and pain with movement of the ear. If the canal is closed, Weber is expected to lateralize to the side of the blocked canal
  • Painful edema with cheesy white discharge, sometimes it is impossible to see the TM
  • Most common causes: Pseudomonas aeruginosa (38%), S. epidermidis (9 percent), and Staphylococcus aureus (8 percent)
  • Malignant otitis externa is commonly seen in diabetics
  • Fungal OM is responsible for approximately 9 percent of ear canal infections. Aspergillus niger (90%) and Candida are the most common organisms

Diagnosis is clinical by otoscopy


Significant crusted, purulent debris and erythema of the ear due to otitis externa

Bacterial otitis externa: 

  • If perforated or chance of perforation: Ciprofloxacin 0.3% and dexamethasone 0.1% suspension: 4 drops BID × 7 days or ofloxacin: 0.3% solution 10 drops once a day × 7 days
  • Cortisporin otic SUSPENSION, which is less irritating than the solution

Fungal otitis externa

  • Topical therapy, anti-yeast for Candida or yeast: 2% acetic acid 3–4 drops QID; clotrimazole 1% solution; itraconazole oral
Advanced treatment notes - summer and swimmers ear

Summer and swimmer’s ear

Acute otitis externa isn’t only from water. This bacterial overgrowth can also occur due to earbuds, eczema, etc.

Choose a topical treatment based on eardrum status, cost, and convenience…regardless of the cause.

Intact eardrum. In most cases, pick neomycin/polymyxin B/ hydrocortisone (Cortisporin, etc) otic SUSPENSION, which is less irritating than the solution…or an otic OR ophthalmic quinolone (ciprofloxacin, ofloxacin).

Keep in mind quinolone EYE drops can be used in the ears…and often cost less. For instance, ofloxacin otic costs up to $130/5 mL…ophthalmic is about $30/5 mL.

Or consider gentamicin or tobramycin eye drops if cost is a concern…since these are only about $15/5 mL.

Explain that the pain should resolve in a few days. Steroid combos (Ciprodex, etc.) may resolve pain a day sooner but can be costly.

Ear tubes or a perforated eardrum. Stick with an otic or ophthalmic quinolone for these patients.

But avoid ANY ear drops that aren’t sterile (Cipro HC, etc)…or that may cause ototoxicity (neomycin, etc).

Pain. Recommend oral acetaminophen or ibuprofen.

Don’t use ear drops for pain. The Rxs (Auralgan, etc) are no longer available, and OTCs (Ear Pain MD, etc) may mask progression. Explain that others (Hyland’s, sweet oil, etc) aren’t likely to help.

Prevention. To dry the ears after water exposure, advise using a hair dryer on low, several inches from the ear…or isopropyl alcohol (Swim-Ear, etc).

Or suggest a home remedy, such as a 1:1 mixture of white vinegar/isopropyl alcohol…or Rx acetic acid 2%. These may even do the trick for MILD symptoms.

Source: Prescribers Letter

Question 1
A 24 year-old patient presents after a recent vacation. He complains of left ear pain. Physical examination reveals an inflamed external auditory canal and the tympanic membrane can not be visualized. Which of the following is the most appropriate treatment?
Oral penicillin
Oral antibiotics are not indicated in acute otitis externa.
Ciprodex otic drops
VoSoL drops
VoSoL drops are utilized as preventive treatment of otitis externa, but are not effective for treatment.
Oral prednisone
Oral prednisone is not indicated in the treatment of acute otitis externa.
Question 1 Explanation: 
Topical steroid/antibiotic drops are most useful in acute bacterial otitis externa.
Question 2
A patient presents complaining of right ear pain and itching. On physical examination you note erythema and edema of the right ear canal with purulent exudate. Palpation of the tragus and manipulation of the auricle is painful. The tympanic membrane is not well visualized. Which of the following is the treatment of choice for this patient?
Amoxicillin is the initial treatment of choice in acute otitis media, not otitis externa.
Aqueous irrigation
Aqueous irrigation is not indicated in the treatment of otitis externa.
Tympanocentesis is not indicated in the treatment of otitis externa.
Polymyxin B sulfate
Question 2 Explanation: 
Polymyxin B sulfate is the treatment of choice for otitis externa.
Question 3
Otitis externa can be differentiated from uncomplicated otitis media by which of the following physical examination findings?
Erythematous tympanic membrane
In otitis externa, the erythema is because the lateral surface of the tympanic membrane is ear canal skin, and therefore is often erythematous.
Mastoid tenderness
Mastoid tenderness is not directly associated with otitis media or otitis externa.
Normal pneumatic otoscopy
Posterior auricular adenopathy
Both otitis media and otitis externa may have posterior auricular adenopathy on examination.
Question 3 Explanation: 
In contrast to acute otitis media, the tympanic membrane moves normally with pneumatic otoscopy in a patient with otitis externa.
Question 4
A 54 year-old type 2 diabetic male presents for follow up evaluation of previously diagnosed persistent otitis externa. Early in the disease process, a CT scan was obtained secondary to non-improvement on antibiotics. Results showed osseous erosion of the floor of the ear canal. He has been on ciprofloxacin 1000 mg twice daily for two months since the CT scan and currently has no further edema, erythema, or exudate from the external auditory canal or surrounding tissue. Which of the following is an appropriate treatment plan?
Continue prophylactic antibiotics for an additional 6 weeks
See C for explanation.
Immediately discontinue antibiotics
See C for explanation.
Obtain gallium scan to ensure reduction of inflammatory process
Skin swab culture of healthy tissue
See C for explanation.
Question 4 Explanation: 
Treatment of malignant external otitis requires prolonged antipseudomonal antibiotic administration often for several months. To avoid relapse, antibiotics should be continued even in the asymptomatic patient, until gallium scanning indicates a marked reduction in the inflammatory process.
There are 4 questions to complete.
Shaded items are complete.

References: Merck Manual · UpToDate

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