A retrospective review of 14 cases of malignant otitis externa

Abstract

Background Malignant otitis externa is an inflammatory condition of the external ear which has the propensity to spread to the skull base. It can be a difficult entity to treat as clinical presentation varies and response to treatment differs between patients. We reviewed cases of malignant otitis externa in our setup to document the epidemiology and outcome of management. Methods This is a retrospective case review observational study from January 2013–December 2017. Fourteen patients diagnosed with malignant otitis externa in our tertiary referral centre were included in the study. Based on hospital protocol, empiric treatment was started. After discharge, the patients follow up visits to the hospital were also documented. Results Otalgia was the most common symptom. Edema and congestion of the external auditory canal were observed in most cases. Diabetes was present in all patients. Three cases had associated facial palsy, and one patient had involvement of 7th, 9th, 10th, 11th and 12 th cranial nerve. Two patients with facial palsy recovered. Pseudomonas aeuroginosa was the most common organism isolated (50%). Conclusions In our series, malignant otitis externa invariably presented with severe otalgia. Lower cranial palsies were also seen. Methods to evaluate complete eradication of disease should be centered on clinical symptoms and signs, but the measurement of erythrocyte sedimentation rate or radiological imaging may be used as a useful adjunct when there is uncertainty.

Malignant Otitis External: Our Experience and Literature Review

“…MEO is an invasive and potentially fatal condition [ 2 ]. It is characterized by challenging management because of the need for long-term therapy requiring regular monitoring [ 1 ].…”

“…Malignant external otitis (MEO) is an invasive infection. It can affect the external auditory canal up to the temporal bone (mastoid process) and the skull base [ 1 – 3 ]. Diagnosis can be delayed with significant morbidity and mortality [ 4 ].…”

“…This pathology affects commonly elderly patients with diabetes and impaired immune systems [ 1 , 2 , 5 ]. In most cases, MEO is caused by Pseudomonas aeruginosa ; Staphylococcus epidermidis , Proteus mirabilis , and fungal infections also have been implicated [ 6 ].…”

“…At presentation, the common symptoms are severe otalgia, hearing loss, and purulent otorrhea. Otoscopic examination reveals edema and granulation tissue in the external ear canal [ 1 , 7 ]. Invasion of the skull base can involve cranial nerves, leading to facial nerve paralysis in most cases and other cranial nerve palsies (IX, X, XII).…”

“…To prevent recurrence after patient’s symptoms have improved, radionuclide scans, such as with Gallium – 67 – citrate ( 67 Ga) or 111 Indium ( 111 In), can be performed to identify areas of active residual infection [ 8 ]. Treatment includes antibiotics (third-generation cephalosporins and fluoroquinolones such as ciprofloxacin) [ 1 , 9 ], local antibiotic washing of the external auditory canal, and finally surgery [ 2 ]. Some patients don’t respond to this treatment because of fungal infection (e.g.…”