Intra-abdominal aortic graft infection: prognostic factors associated with in-hospital mortality.

BACKGROUND: Mortality associated with aortic graft infection is considerable. The gold standard for surgical treatment remains explantation of the graft. However, prognostic factors associated with early mortality due to this surgical procedure are not well-known. METHODS: Retrospective analysis of patients admitted in our center between January 2006 and October 2011 for aortic graft infection. The primary endpoint was in-hospital mortality. A bivariate analysis of characteristics of patients associated with in-hospital outcome was performed. RESULTS: Twenty five evaluable patients were studied. All patients were male. Their mean age was 67 ± 8.4 years. Most of them (92%) had severe underlying diseases. An in situ prosthetic graft replacement, mainly using cryopreserved arterial allografts, was performed in all patients, excepted one who underwent extra-anatomic bypass. Causative organisms were identified in 23 patients (92%). The in-hospital mortality rate was 48%. Among pre-operative characteristics, age ≥ 70 years, creatinine ≥ 12 mg/L and C reactive protein ≥ 50 mg/L were significantly associated with in-hospital mortality. Hospital mortality rates increased with the number of risk factor present on ICU admission, and were 0%, 14.3%, 85.7% and 100% for 0, 1, 2 and 3 factors, respectively. The only intra-operative factor associated with prognosis was an associated intestinal procedure due to aorto-enteric fistula. SAPS II, SOFA score and occurrence of medical or surgical complications were postoperative characteristics associated with in-hospital mortality. CONCLUSION: Morbidity and mortality associated with surgical approach of aortic graft infections are considerable. Age and values of creatinine and C Reactive protein on hospital admission appear as the most important determinant of in hospital mortality. They could be taken into account for guiding the surgical strategy.

Factors predictive of treatment failure in staphylococcal prosthetic vascular graft infections: a prospective observational cohort study: impact of rifampin.

BACKGROUND: There exists considerable debate concerning management of prosthetic vascular graft infection (PVGI), especially in terms of antimicrobial treatment. This report studies factors associated with treatment failure in a cohort of patients with staphylococcal PVGI, along with the impact of rifampin (RIF). METHODS: All data on patients with PVGI between 2006 and 2010 were reviewed. Cure was defined as the absence of evidence of infection during the entire post-treatment follow-up for a minimum of one year. Failure was defined as any other outcome. RESULTS: 84 patients (72 M/12 F, median age 64.5 ± 11 y) with diabetes mellitus (n = 25), obesity (n = 48), coronary artery disease (n = 48), renal failure (n = 24) or COPD (n = 22) were treated for PVGI (median follow-up was 470 ± 469 d). PVGI was primarily intracavitary (n = 47). Staphylococcus aureus (n = 65; including 17 methicillin-resistant S. aureus) and coagulase-negative Staphylocococcus (n = 22) were identified. Surgical treatment was performed in 71 patients. In univariate analysis, significant risk factors associated with failure were renal failure (p = 0.04), aortic aneurysm (p = 0.03), fever (p = 0.009), aneurysm disruption (p = 0.02), septic shock in the peri-operative period (p = 0.005) and antibiotic treatment containing RIF (p = 0.03). In multivariate analysis, 2 variables were independently associated with failure:septic shock [OR 4.98: CI 95% 1.45-16.99; p=0.01] and antibiotic containing rifampin [OR: 0.32: CI95% 0.10-0.96; p=0.04]. CONCLUSION: Results of the present study suggest that fever, septic shock and non-use of antibiotic treatment containing RIF are associated with poor outcome.

Vascular graft infections.

PURPOSE OF REVIEW: This review provides a focus on infections of prosthetic vascular grafts used to treat peripheral arterial diseases. RECENT FINDINGS: The incidence of infections varies between 1 and 6%. Risk factors of infection are not well identified. Main causative pathogens are Gram-negative bacilli, Staphylococcus aureus, and coagulase-negative staphylococci, without clear differences according to location of graft and time of onset of infection. There is no consensual diagnostic criterion. The basic principles for management of graft infections have been known for many years. A surgical approach combining graft excision, complete debridement, and maintaining distal vascular flow is required. Antimicrobial therapy is always instituted to reduce sepsis and prevent secondary graft infection, but there are no evidence-based data to recommend any regimen. However, antibiotics should have bactericidal activity whatever the bacteria growth phase, reduce the microbial burden, penetrate within the biofilm, and prevent further biofilm formation. Mortality and morbidity from these infections remain significant. SUMMARY: A multidisciplinary approach with a limited number of reference centres, recruiting sufficient numbers of patients to perform controlled trials, and to provide expert recommendations, could be the best way to answer unresolved questions and improve the prognosis.

Tolerability of High Doses of Daptomycin in the Treatment of Prosthetic Vascular Graft Infection: A Retrospective Study.

INTRODUCTION: In treatment of prosthetic vascular graft infection (PVGI), appropriate antimicrobial treatment is crucial for controlling the septic process and preventing re-infection of the new graft. Glycopeptides are the mainstay of treatment for device-related infections by methicillin-resistant Staphylococcus aureus strains, but with some limitations, especially concerning vancomycin-intermediate and glycopeptide-intermediate S. aureus. We report our experience using a high dose of daptomycin (DAP) for treatment of PVGI. METHODS: We reviewed medical reports of 26 patients treated with high doses of DAP (>8 mg/kg) and beta-lactams/aminosides for PVGI, defined as positive bacterial culture of intraoperative specimens or blood samples and/or clinical, biological, and radiological signs of infection. Clinical success was defined by resolution of all clinical signs at the end of follow-up, without the need for additional antibiotic therapy, and/or negative culture in case of new surgery. RESULTS: Cultures of intraoperative samples were positive in 21 patients (80.8%). Blood and intraoperative cultures were concomitantly positive in 10 patients. The main microorganism identified in microbiological samples was S. aureus (n = 18). Surgery was performed in 23 patients (88.4%). The mean duration of the DAP regimen was 12.3 ± 11.9 days. DAP was discontinued in 26 patients [need to switch to microbiological results (n = 19), bacterial pneumonia (n = 2), and increased creatine phosphokinase levels (n = 4)]. One patient had myalgia, while 9 received concomitant statins. CONCLUSION: High-dose DAP therapy shows a satisfactory toxicity profile even in severely ill patients with multiple comorbidities, and may favorably compete with vancomycin, especially concerning the risk of induced nephrotoxicity.

Vascular graft infections in the intensive care unit: clinical spectrum and prognostic factors.

OBJECTIVES: To report clinical characteristics and prognosis of vascular graft infections in Intensive Care Unit (ICU). METHODS: Thirty seven patients consecutively admitted in ICU for suspected or definite vascular graft infection between January 2006 and June 2009 were included. RESULTS: Staphylococcus species (n = 18) and enterobacteriae (n = 16) were the most frequent causative organisms. Twenty six patients (70%) needed mechanical ventilation. Further surgical procedures were performed in 7 patients (19%). In case of definite infection, mortality in ICU was 33%. In non survivors, shock (92% vs 42%, p = 0.01), age > 70 years (73% vs 27%, p = 0.04), POSSUM score > 45 (73% vs 27%, p = 0.04) and extra-anatomic bypass (45% vs 14%, p = 0.05) were more frequent, intra-operative volume of red cells transfusion (6 ± 3 vs 3 ± 2 units, p = 0.006) and of fresh frozen plasma (2.8 ± 2.8 vs 0.7 ± 1.2 units, p = 0.02), and SAPS II score (58 ± 26 vs 38 ± 17, p = 0.03) were higher. Proportion of adequate initial antibiotic therapy was similar in survivors and non survivors (91% vs 100%, p = 0.4). Proportion of patients treated with an aminoglycoside tended to be higher in survivors (59% vs 27%, p = 0.07). By multivariate analysis, only shock was associated with death in ICU (AOR: 16.3; 95% CI: 1.7-152.1; p = 0.01). CONCLUSIONS: Vascular graft infection carries high morbidity and mortality rates in ICU. Extra-anatomic bypass might be associated with higher mortality. Early aminoglycoside prescription might be protective.