A 16-year-old Japanese female complaining of long-lasting suppurative otorrhea, otalgia, hearing loss, and vertigo was referred to our university hospital. Antibiotic treatment did not resolve the otorrhea, and tympanoplasty and mastoidectomy were performed. Pathological analysis of the mastoid mucosa revealed an Actinomyces infection in her middle ear. Antibiotic therapy with penicillin for 3 months controlled this infection, and there has been no clinical evidence of infection recurrence in the 4 years following.
Actinomycosis should be considered in cases of suppurative otorrhea with granulation tissue, culture-insensitive pathogens, and bony erosion. Differential diagnoses include malignancy, cholesteatoma, tuberculosis, and otitis media with antineutrophil cytoplasmic antibody associated vasculitis (OMAAV). Culture identification of Actinomyces is difficult; hence, definitive diagnosis for an Actinomyces infection is usually based on pathological examination. Penicillin is the first choice antibiotic for treatment of Actinomyces infection, and prolonged antibiotic therapy for 3–12 months is recommended for preventing recurrence.
