Tularemia from a cat bite: Case report and review of the literature.

BACKGROUND: Patients frequently present to primary care or urgent care with infections related to cat bites. First-line treatment includes antibiotics targeting traditional cat-associated pathogens such as Pasteurella multocida.Francisella tularensis is increasingly recognized in cat-associated infections but does not respond to first-line antibiotics. F. ularensis may also relapse after treatment. This case highlights the need for clinicians to be aware that F. tularensis could be present in cat-related infections not responding to usual first-line antibiotics.

CASE PRESENTATION: A 64-year-old woman presented to the hospital with fevers and finger swelling two weeks after sustaining a cat bite to her finger. Prior to admission, she had been treated with ceftriaxone and clindamycin without improvement. She failed to improve on vancomycin and piperacillin-tazobactam. She underwent debridement with intraoperative cultures growing F. tularensis. Her antibiotics were switched to ciprofloxacin (for F. tularensis) and oral amoxicillin-clavulanate (for coverage of other feline oral flora) with improvement. Antibiotics were stopped after three weeks but she developed clinical relapse. She was then treated with six weeks of doxycycline with complete resolution. This case occurred during an increase of tularemia in the local cat population identified by the health department.

CONCLUSIONS: This case illustrates the importance of considering F. tularensis in cat-related infections not improving with standard antibiotic therapy. The case also underscores the importance of recognizing relapse of F. tularensis infection as a common complication, as well as the importance of engaging with public health authorities to be aware of changes in epidemiology that may affect patient care.