Rare Actinobacillus infection of the cavernous sinus causing painful ophthalmoplegia: Case report

OBJECTIVE AND IMPORTANCE: Actinobacillus actinomycetemcomitans is a gram-negative coccobacillus that is known to cause a wide array of clinical infections in debilitated patients, including periodontal disease, soft tissue abscess, pleural empyema, endocarditis, cerebral abscess, and meningitis. We report a rare A. actinomycetemcomitans cavernous sinus abscess that caused painful ophthalmoplegia in a healthy man. CLINICAL PRESENTATION: A 34-year-old man presented with a 3-month history of acute onset of left-sided retro-orbital pain that progressed to a complete left Cranial Nerve VI palsy and Cranial Nerve V1 and V2 hypesthesia. Magnetic resonance imaging revealed the presence of an enhancing lesion in the left cavernous sinus, which encased and narrowed the ipsilateral intracavernous segment of the internal carotid artery. Routine blood and cerebrospinal fluid analyses were normal. Tolosa-Hunt syndrome was suspected, and the patient was treated with high-dose corticosteroids. An open biopsy was performed after failed prolonged corticosteroid therapy. INTERVENTION: A left frontotemporal craniotomy and cavernous sinus exploration through an interdural approach were performed. A soft reddish mass was found in the cavernous sinus around Cranial Nerve V1 and V2. Multiple biopsies were obtained. Pathological analysis revealed a purulent infection containing multiple gram-negative coccobacilli. The patient's pain improved immediately, and cranial neuropathy resolved during the next several weeks. After cultures demonstrated growth of A. actinomycetemcomitans, a regimen of orally administered amoxicillin and metronidazole was initiated. Eight months after surgery, the patient was free of symptoms and a repeat magnetic resonance imaging scan was normal. CONCLUSION: We present a rare bacterial abscess of the cavernous sinus causing painful ophthalmoplegia. In patients who present with presumed Tolosa-Hunt syndrome and do not improve with prolonged high-dose corticosteroid therapy, an open biopsy is recommended to exclude a bacterial infection.