Ryan Gouveia E Melo1, Beatriz Martins2, Diogo Mendes Pedro3, Carla Mimoso Santos4, António Duarte5, Ruy Fernandes E Fernandes6, Pedro Garrido5, Luís Mendes Pedro6. 1. Faculty of Medicine, University of Lisbon, Hospital Santa Maria (Centro Hospitalar Universitário Lisboa Norte), Lisbon, Portugal; Division of Vascular Surgery, Heart and Vessels Department, Hospital Santa Maria (Centro Hospitalar Universitário Lisboa Norte), Lisbon, Portugal; Lisbon Academic Medical Centre, Lisbon, Portugal. Electronic address: ryan@campus.ul.pt. 2. Faculty of Medicine, University of Lisbon, Hospital Santa Maria (Centro Hospitalar Universitário Lisboa Norte), Lisbon, Portugal. 3. Faculty of Medicine, University of Lisbon, Hospital Santa Maria (Centro Hospitalar Universitário Lisboa Norte), Lisbon, Portugal; Lisbon Academic Medical Centre, Lisbon, Portugal; Infectious Disease Department, Hospital Santa Maria (Centro Hospitalar Universitário Lisboa Norte), Lisbon, Portugal. 4. Faculty of Medicine, University of Lisbon, Hospital Santa Maria (Centro Hospitalar Universitário Lisboa Norte), Lisbon, Portugal; Lisbon Academic Medical Centre, Lisbon, Portugal; Grupo de Coordenação Local do Programa de Prevenção e Controlo de Infeção e Resistência aos Antimicrobianos do Centro Hospitalar Universitário Lisboa Norte, Lisbon, Portugal; Infectious Disease Department, Hospital Santa Maria (Centro Hospitalar Universitário Lisboa Norte), Lisbon, Portugal. 5. Division of Vascular Surgery, Heart and Vessels Department, Hospital Santa Maria (Centro Hospitalar Universitário Lisboa Norte), Lisbon, Portugal; Lisbon Academic Medical Centre, Lisbon, Portugal. 6. Faculty of Medicine, University of Lisbon, Hospital Santa Maria (Centro Hospitalar Universitário Lisboa Norte), Lisbon, Portugal; Division of Vascular Surgery, Heart and Vessels Department, Hospital Santa Maria (Centro Hospitalar Universitário Lisboa Norte), Lisbon, Portugal; Lisbon Academic Medical Centre, Lisbon, Portugal.
Abstract
BACKGROUND: Vascular graft infections are a serious complication in vascular surgery. Correct antibiotic therapy targeted to the most likely infecting species is essential to treat these patients, although the bacterial epidemiology and pathogenesis are still not completely understood. We analyzed the behavior of vascular graft infections and the microbiologic patterns of resistance. METHODS: A 10-year (2008-2018), single-center, retrospective cohort study was performed of all patients admitted with vascular graft infection identified by positive direct graft cultures. An extensive microbiologic study was performed to analyze the bacterial strains, antibiotic resistance and sensitivity, and prevalence stratified by the year. RESULTS: A total of 72 vascular graft infections with positive graft cultures occurring in 65 patients were found. Their mean age was 67 ± 9.6 years, and 85% were men. Infection-related mortality was 11%. Of the 65 patients, 14 had undergone aortobifemoral bypass, 13 axillofemoral bypass, 5 femorofemoral bypass, 27 femoropopliteal bypass, and 4 femoral endarterectomy with synthetic patch angioplasty. The median interval from the index procedure to infection was longer for intracavitary than for extracavitary grafts (P = .011). Of the 72 infections, 48 were monomicrobial and 24 were polymicrobial. Gram-negative bacteria were predominantly identified in intracavitary graft infections (54%). In contrast, gram-positive bacteria were most frequent in the extracavitary graft group (58%). Multidrug-resistant bacterial species occurred more frequently in early graft infections (P = .002). Throughout the study duration, an overall decrease in gram-positive infections and an increase in gram-negative infections was observed, especially in extensively drug-resistant strains. A similar progression was found in all nosocomial infections. CONCLUSIONS: The present study has shown that vascular graft infection microbiology changed in accordance with graft location and interval to infection from revascularization surgery and had also evolved over the study period with patterns similar to those for all nosocomial infections. This highlights the importance of studying the specific microbiology of each healthcare center and its relationship to vascular graft infections to achieve the best treatment possible.
BACKGROUND:Vascular graft infections are a serious complication in vascular surgery. Correct antibiotic therapy targeted to the most likely infecting species is essential to treat these patients, although the bacterial epidemiology and pathogenesis are still not completely understood. We analyzed the behavior of vascular graft infections and the microbiologic patterns of resistance. METHODS: A 10-year (2008-2018), single-center, retrospective cohort study was performed of all patients admitted with vascular graft infection identified by positive direct graft cultures. An extensive microbiologic study was performed to analyze the bacterial strains, antibiotic resistance and sensitivity, and prevalence stratified by the year. RESULTS: A total of 72 vascular graft infections with positive graft cultures occurring in 65 patients were found. Their mean age was 67 ± 9.6 years, and 85% were men. Infection-related mortality was 11%. Of the 65 patients, 14 had undergone aortobifemoral bypass, 13 axillofemoral bypass, 5 femorofemoral bypass, 27 femoropopliteal bypass, and 4 femoral endarterectomy with synthetic patch angioplasty. The median interval from the index procedure to infection was longer for intracavitary than for extracavitary grafts (P = .011). Of the 72 infections, 48 were monomicrobial and 24 were polymicrobial. Gram-negative bacteria were predominantly identified in intracavitary graft infections (54%). In contrast, gram-positive bacteria were most frequent in the extracavitary graft group (58%). Multidrug-resistant bacterial species occurred more frequently in early graft infections (P = .002). Throughout the study duration, an overall decrease in gram-positive infections and an increase in gram-negative infections was observed, especially in extensively drug-resistant strains. A similar progression was found in all nosocomial infections. CONCLUSIONS: The present study has shown that vascular graft infection microbiology changed in accordance with graft location and interval to infection from revascularization surgery and had also evolved over the study period with patterns similar to those for all nosocomial infections. This highlights the importance of studying the specific microbiology of each healthcare center and its relationship to vascular graft infections to achieve the best treatment possible.