Osteonecrosis of the External Auditory Canal Associated With Oral Bisphosphonate Therapy: Case Report and Literature Review

Objective: To present the first case of a patient with oral bisphosphonates-associated ear canal osteonecrosis (BPECO), review previously published cases, and suggest a definition of BPECO. Patient: A 79-year-old woman with left otorrhea and earache was treated for otitis externa for 2 months. The examination revealed a deep floor of the left ear canal defect. The bisphosphonates were discontinued. By the end of the 6-week-course of intravenous antibiotics, the bone defect progression ceased. Already a month later, the defect was lined from approximately 50%. Unfortunately, the patient was lost to follow-up at this stage. She was on oral bisphosphonates for 10 years for severe osteoporosis. She had never been exposed to radiotherapy or had any surgery in the left ear. She admitted to be a habitual cotton bud user for aural toilet. Results: A CT scan showed an aggressive lobulated mass consistent with carcinoma. A biopsy suggested osteomyelitis with no evidence of malignancy. The final diagnosis was agreed to be the first case of oral BPECO. Intervention: Debridement, intravenous antibiotics, and cessation of bisphosphonates Conclusion: The BPECO is not very well-known clinical diagnosis among ENT surgeons and, therefore, often misdiagnosed for ear canal cholesteatoma, malignant otitis externa, or temporal bone malignancies. It seems reasonable to re-review patient's medical history with focus on BP medication in cases with negative biopsy. Although the BP osteonecrosis is a rare phenomenon, the large volume of BP prescription makes the number of patients at risk significant.