Vascular prosthetic infection by Francisella tularensis: a unique case report

Tularemia is a rare zoonosis caused by Francisella tularensis. Clinical presentation is variable and typically associated with people living in rural areas with compatible epidemiological exposure. Vascular prosthetic infections by this microorganism are exceptionally uncommon. We report a unique case of a vascular prosthetic infection by F. tularensis, a previously undescribed complication.

We describe a 76-year-old male, with multiple femoro-femoral cross bypass procedures, presented with progressively enlarging painful left femoral mass and one week of malaise, low-grade fever, and anorexia. Angio-CT demonstrated inflammatory/infectious collections around the bypass graft. Periprosthetic samples grew Francisella tularensis, confirmed by PCR and serology, while blood cultures remained negative. Given the patient's stable condition, deferred surgery was performed. The procedure consisted of explantation of the previous femoro-femoral bypass, a new left-to-right profunda femoro-femoral bypass, and an additional bypass from the cross to the left profunda femoral artery, all using cryopreserved arterial grafts. Cultures from the prosthesis, anastomosis, fluid, and subcutaneous tissue were uniformly positive for F. tularensis.Antibiotic therapy was initiated in collaboration with internal medicine, consisting of intravenous gentamicin and ciprofloxacin for two weeks during hospitalization, followed by four additional weeks of intravenous ciprofloxacin via a home-hospitalization program. At six-month follow-up, the patient remained asymptomatic with no evidence of infection.

Prosthetic infections caused by F. tularensis are exceedingly rare. Reported cases in the literature are limited to joint prostheses, cardiac valves, and a single aortic endograft. Optimal management requires complete graft removal, wide surgical debridement, and targeted antimicrobial therapy.