An Unusual Presentation of Mycotic Popliteal Artery Pseudoaneurysm due to Pasteurella multocida Infection

Area of Science:

• Vascular Surgery
• Infectious Diseases
• Bacteriology

Background:

• Mycotic aneurysms are uncommon vascular complications, often associated with systemic infections.
• Pasteurella multocida, a zoonotic pathogen, is a rare but recognized cause of infectious aneurysms.
• Popliteal artery aneurysms, particularly pseudoaneurysms, require prompt diagnosis and management to prevent limb-threatening complications.

Observation:

• A 76-year-old male presented with acute limb ischemia secondary to a superinfected right limb.
• Initial treatment for presumed knee arthritis and subsequent antibiotic therapy did not resolve the ischemia.
• Imaging revealed a ruptured pseudoaneurysm of the right popliteal artery.

Findings:

• Surgical exploration and explantation of the ruptured popliteal artery were performed, followed by a femoropopliteal bypass.
• Bacterial analysis of the aneurysm sac identified Pasteurella multocida as the causative agent.
• This represents the first reported case of a popliteal artery pseudoaneurysm specifically attributed to Pasteurella multocida infection.

Implications:

• Highlights the importance of considering infectious etiologies, including zoonotic pathogens like Pasteurella multocida, in the differential diagnosis of pseudoaneurysms.
• Emphasizes the critical role of vascular surgery and appropriate antibiotic therapy in managing complex cases of infected pseudoaneurysms.
• Contributes to the understanding of rare vascular infections and informs clinical practice regarding atypical pathogens in aneurysm formation.