Case Series
A 74-year-old male with severe left sided OE presented to the emergency
department (ED) with worsening left sided otalgia and external auditory
canal (EAC) granulations. This was on the background of insulin
dependent type-2 diabetes mellitus (T2DM) and hypertension (HTN). A CT
of the petrous bones was requested. In the interim, granulation tissue
in the external ear was cauterized with silver nitrate. The Radiologist
described a marked bony erosion and the subsequent report demonstrated“perforation of the tympanic membrane, opacification of the
tympanic cavity with partial erosion of the ossicles” (Figure 1). Left
sided malignant OE and acute mastoiditis were suspected and therefore
the patient was admitted and commenced intravenous tazobactam and
piperacillin (Tazocin). On further clinical correlation and discussion
between the head and neck radiologist and consultant otolaryngologist,
bony erosion, perforation and intracranial extension were ruled out. A
diagnosis of left sided otitis externa was made, and the patient
completed an extended course of intravenous outpatient antibiotic
therapy (OPAT) to prevent progression to malignant otitis externa.
Similarly, another patient, a 75-year-old male, was admitted with
suspected left sided malignant OE on the background of long-standing OE.
He also had a history of T2DM on insulin and HTN. Over-granulation
tissue noted in his ear canal was cauterized with silver nitrate. A
subsequent CT reported an unidentified foreign body in the canal with
extensive soft tissue swelling giving an impression of a wick in situ.
(Figure 2). Again, on further clarification between the consultants in
both departments, it was concluded the CT did not show eroded bone,
rather there appeared to be an artefact in the images as a result of
silver nitrate usage. The patient had already been treated with
intravenous Tazocin and so was discharged with a long course of
ciprofloxacin and meropenem.
The final patient was a 58-year-old female with recurrent OE and a
history of previous eustachian tube dysfunction with tuboplasty in 2013.
She presented to clinic with an 18-month history of right sided otalgia
and discharge. Swabs were positive for achromobacter
xylosoxidans . Despite multiple courses of topical antifungals
(betamethasone and clotrimazole) and oral antibiotics during these 18
months, the symptoms had not resolved and therefore she underwent a CT
head for suspected necrotizing OE. Alarmingly, the CT reportedly
identified “multiple highly radiopaque foci in the external
auditory canal, suggestive of a foreign body” (Figure 3). Clinical
examination prior to and following CT imaging did not reveal any foreign
bodies however, there was evidence of recent silver nitrate use to treat
over-granulation tissue as well as eczematic skin within the ear canal.
The patient was treated for acute OE with local and systemic antibiotics
and made a complete recovery.