Meningitis caused by Pasteurella multocida in a dog owner without a dog bite: clonal lineage identification by MALDI-TOF mass spectrometry

Matthieu Bardou, Estelle Honnorat, Gregory Dubourg, Carine Couderc, Pierre Edouard Fournier, Piseth Seng, Andreas Stein

Pasteurella multocida meningitis in an immunocompetent patient is rare and commonly occurs after animal bite. To our knowledge, only 48 cases have been reported in the literature since 1989. P. multocida meningitis is commonly linked to animal contagion. Here we report on a new case of P. multocida meningitis in an immunocompetent patient who is a dog owner without a dog bite. We used the matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry to investigate the clonal lineage between animal and human isolates. In our case, a 25-year-old immunocompetent French Caucasian woman with nothing notable in her medical history was admitted for meningitis caused by P. multocida. Clonal lineage of P. multocida strains from cerebrospinal fluid and blood culture and her dog's oral cavity has been recognized by MALDI-TOF mass spectrometry dendrograms and clustering of the 21 P. multocida isolates in our centres. She was treated by a combination of intravenous ceftriaxone (2 g/day) and oral levofloxacin (1 g/day). She was discharged on the 6th day of admission. The antimicrobial therapy was conducted for 15 days. The dog was treated by clavulanic-acid amoxicillin for 3 weeks by the veterinarian. The evolution of the patient at the 5th month after the end of the antimicrobial therapy was normal without any neurological after-effects. The meningitis caused by P. multocida could be considered a cause of human meningitis in dog lovers without an animal bite. MALDI-TOF mass spectrometry should be considered as it is an accurate tool to identify clonal lineage between animal and human isolates.