Septic Arthritis and Osteomyelitis Due to Bordetella petrii.

We report a case of Bordetella petrii elbow septic arthritis and osteomyelitis that resulted from a dirt bike accident in Hawai‘i. Initial incision and drainage followed by one month of oral doxycycline were given. Because of persistent infection of the elbow, additional 10 weeks of intravenous piperacillin/tazobactam and repeated surgeries were required to cure this infection. B. petrii was isolated from the synovial fluid and identification was obtained using 16S rRNA sequencing showing the highest match of 99.3% with B.petrii type strain DSM 12804. This was also confirmed with matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS; Bruker Daltonics, Inc., Billerica, MA). The Bordetella genus includes nine species. The most noteworthy is B. pertussis, and B. parapertussis, but in the past 15 years, five additional species were reported in human infection, including B. hinzii, B. holmesii, B. trematum, B.petrii, and B. ansorpii. This is only the third human clinical case report regarding bone or joint infection caused by B. petrii, and the first case reported in Hawai‘i. Our case, and literature review, suggests that carbapenems, piperacillin/tazobactam, tetracycline, and trimethoprim/sulfamethoxazole are good treatment options. Our case demonstrated resistance to cefepime, which suggest the high probability of resistance to cephalosporin in general. The notable discrepancies with previous reports were that our strain was susceptible to tetracycline and levofloxacin. The susceptibility information from our case and others found in the literature will assist in the empiric choice of antibiotics.