A Case of Masked Mastoiditis Caused by an Enterococcus, with Labyrinthitis and Brain Abscess

Abstract

Acute hearing loss can arise from a variety of disorders, with many cases treated as deafness of sudden onset. We report the case of a patient who presented with hearing loss, vertigo, facial palsy and brain abscess due to masked mastoiditis.

The patient, a 54-year-old man was referred to us with acute hearing loss on the right side and vertigo. He was started on treatment with an oral steroid, as a case of sudden-onset deafness. He developed right facial nerve palsy 10 days later, and a headache and right abducens nerve palsy 28 days later. Imaging examinations revealed pathological changes in the mastoid with the posterior tympanum and a cerebral abscess. The cerebral abscess failed to respond to antibiotic therapy, and mastoidectomy and tympanoplasty were carried out. A review of the past medical history of the patient revealed that he had been diagnosed as having otitis media 2 months earlier, which was still persistent. Enterococcus gallinarum, a rare anaerobic bacterium, was isolated from the middle ear fluid by bacterial culture. Masked mastoiditis without obvious inflammatory findings is difficult to diagnose, and careful observation is required.