2016 Volume 147 Pages 14-15
Malignant external otitis is a severe infection of the external auditory canal, most commonly caused by Pseudomonas aeruginosa in elderly patients with diabetes. Due to the host’s immunocompromised state, malignant external otitis may easily lead to osteomyelitis of the skull base, which may be associated with potential life-threatening complications needing urgent treatment.
Treatment of osteomyelitis consists of debridement, systemic antibiotic administration and management of the immunosuppressed state of the patient. However, in the case of skull base osteomyelitis, complete debridement is often difficult because of anatomical constraints.
We present a case of atypical temporal bone osteomyelitis occurring in a healthy woman without diabetes or pseudomonas infection. A 25-year-old woman was admitted to our hospital with the chief complaint of severe right otalgia which could not be controlled even by thrice-daily intake of painkillers. A slightly reddened skin lesion was found in the bony ear canal; however, neither active aural discharge nor inflammatory stenosis of the canal was found. CT scan showed an osteolytic lesion in the right bony ear canal. Malignancy, osteomyelitis or other unspecified lesion was suspected, and exploratory surgery was performed. Elevation of the tympanomeatal flap revealed eroded bones just beneath the reddened skin, which were completely drilled out by retroauricular mastoidectomy. The dissected specimens were composed of eroded bones, with fibrosis and infiltration by lymphoid and plasma cells. Therefore, the patient was finally diagnosed as having osteomyelitis of the temporal bone. Her clinical symptoms resolved immediately after the surgery, suggesting that complete debridement was effective for controlling the disease.
In cases of prolonged and severe otalgia not responsive to ordinary treatments, osteomyelitis should be considered and CT is recommended for early diagnosis and surgical intervention.
