Capnocytophaga canimorsus, a gram-negative rod found in the oral flora of dogs and cats, is an extremely rare cause of bacterial meningitis. It is more frequently observed in immunocompromised individuals and diagnosis is often delayed due to its slow growth on culture media.

A 38-year-old female presented with 2 days history of worsening headache, nausea, and bilateral hearing loss.  Neurological exam was only notable for bilateral hearing loss. Cerebrospinal fluid (CSF) studies revealed significantly elevated WBCs (4,612/cmm) with 79% neutrophils, elevated protein (348mg/dL), and low glucose (<1mg/dL), consistent with bacterial meningitis. Vancomycin and ceftriaxone were initiated. Blood and CSF cultures returned growing C. canimorsus and she was continued on ceftriaxone. MRI brain was unremarkable. She denied being bitten by her dogs and cat but was potentially scratched and licked by her dogs. On day 4 of presentation, otolaryngology and neurology were consulted for worsening hearing loss. She was started on a trial of methylprednisolone 60 mg daily for 5 days.  MRA head did not show any aneurysm and CT temporal bone did not exhibit signs of fibrosis. HIV antibody testing was negative. Audiogram demonstrated precipitous sloping indicating severe bilateral hearing loss. She completed a 15-day steroid taper with mild improvement in hearing. Repeat audiogram in 3 months showed improvement in higher frequencies and patient reports subjective improvement of her hearing.

We describe the case of a young immunocompetent woman who developed severe bilateral sensorineural hearing loss due to C. canimorsus meningitis. While early initiation of steroids in patients with pneumococcal meningitis is known to be associated with reduced risk of post-meningeal hearing loss, its utility in patients with C. canimorsus meningitis is unknown. This is the first case of steroid use in C. canimorsus meningitis with reported improvement in hearing, suggesting a potential therapeutic benefit to these patients.