Pathology Quiz Case 1

Abstract

A 61-YEAR-OLD MAN PRESENTED WITH SEvere otalgia and otorrhea. He had a 35year history of right-sided intermittent otorrhea, aural fullness, and tinnitus and a 3-month history of decreased balance. Topical and systemic antibiotic therapy was initiated, but his symptoms persisted, and new symptoms of severe facial pain and fever developed. He had no history of immunocompromise. Physical examination revealed an edematous, mildly erythematous right external auditory canal, with purulent discharge obscuring the tympanic membrane. There was no pain with movement of the pinna. Temperature, light touch, and sharp and dull stimuli were reduced in the right trigeminal distribution. Audiometric testing showed a down-sloping, moderate to profound mixed hearing loss in the patient’s right ear. Computed tomography of the temporal bone with intravenous contrast showed opacification of the right middle ear, sclerotic mastoid with erosion of the carotid canal adjacent to the eustachian tube, and a peripherally enhancing low-density petrous apex collection (Figure1). Gadolinium-enhanced magnetic resonance imaging also demonstrated a low-signal focus in the right petrous apex, with enhancement and thickening of the cisternal portion of the right trigeminal nerve and meninges of the posterior clivus and sphenoid wing (Figure 2). Hematoxylin-eosinstainingofbiopsyspecimensofgranulomatous tissue from the protympanum and petrous apex demonstratedacuteandchronicallyinflamedciliatedcolumnarepitheliumandgranulation tissue(Figure3).GrocottGomori methenamine-silver nitrate staining (Figure 4) showedaggregatesofgram-positive filamentousbacteria in entangledmasses focallybreakingup intococcoidandbacillary forms.Cultures identifiedProteusmirabilis,Enterococcus avium, and multiple strains of Corynebacterium species with sensitivity to ciprofloxacin. What is your diagnosis?