Contiguous spread from superficial infection or intraabdominal infection
Direct inoculation during subsequent procedure
Hematogenous spread, less common after the early postoperative period (first 2 months) due to endothelialization
Clinical Manfestations
Varies by site of graft and infection
Can be early-onset (first 2 months) or late-onset (after 2 months)
Late-onset infections tend to be indolent without sepsis
Samson Classification
Classification of peripheral arterial prosthetic graft infections 1
Minor infections
Group I: infection no deeper than the dermis
Group II: infection of subcutaneous tissue without visible involvement of graft
Group III: infections involving graft but not anastomosis
Group IV: infections involving exposed anastomosis without bacteremia or anastomotic bleeding
Group V: infections involving graft-to-artery anastomosis with bacteremia or anastomotic bleeding
Diagnosis
Diagnosis is made clinically
Ultrasound is usually the initial imaging procedure, followed by CTA or MRI if US is equivocal
CT- or US-guided aspiration can be helpful for a microbiologic diagnosis
Management
Local infection without graft involvement: antibiotics with or without incision and drainage (groups I & II)
Duration 2 to 4 weeks
Infection involving graft but without bacteremia or anastomotic bleeding (groups III & IV)
Incision and drainage
Preservation of graft, or reconstruction with allograft, autograft, or prosthetic material
4 to 6 weeks of IV followed by 3 to 6 months of oral
Infection with bacteremia or anastomotic bleeding (group V)
Extra-anatomic revascularization followed by graft excision
4 to 6 weeks IV followed by 6 months oral
Further Reading
Vascular Graft Infections, Mycotic Aneurysms, and Endovascular Infections: A Scientific Statement From the American Heart Association. Circulation. 2016;134:e412-e460. doi: 10.1161/CIR.0000000000000457
References
^Russell H. Samson, Frank J. Veith, Gary S. Janko, Sushil K. Gupta, Larry A. Scher. A modified classification and approach to the management of infections involving peripheral arterial prosthetic grafts. Journal of Vascular Surgery. 1988;8(2):147-153. doi:10.1016/0741-5214(88)90402-8.
