Table 1. Comparison of patient characteristics and clinical presentation with respect to graft location in patients with prosthetic vascular graft infection.* .
| Variable | Thoracic-Aortic PVGI (n = 24) | Abdominal-Aortic PVGI (n = 27) | Peripheral-Arterial PVGI (n = 10) | p-Value† |
| Patient Characteristics at the Time of Graft Infection | ||||
| Median age in years | 58 (IQR 48–65) | 70 (IQR 66–76) | 74 (IQR 57–78) | <0.001 |
| Male patients, n | 21 (87.5%) | 25 (92.6%) | 7 (70.0%) | 0.202 |
| Median BMI in kg/m2 | 27 (IQR 24–28) | 25 (IQR 23–28) | 25 (IQR 20–27) | 0.622 |
| Patients with a ICU stay, n | 9 (37.5%) | 11 (40.7%) | 3 (30.0%) | 0.938 |
| Cardiovascular disease‡, n | 11 (45.8%) | 18 (66.7%) | 10 (100%) | 0.007 |
| Diabetes mellitus, n | 4 (16.7%) | 5 (18.5%) | 1 (10.0%) | 0.823 |
| COPD, n | 4 (16.7%) | 8 (29.6%) | 3 (30.0%) | 0.533 |
| Renal impairment§, n | 5 (20.8%) | 13 (48.1%) | 1 (10.0%) | 0.037 |
| Complications at the Time of Graft Implantation | ||||
| Open graft implantation, n patients | 23 (95.8%) | 26 (96.3%) | 10 (100%) | 0.813 |
| Emergency surgery, n patients | 5 (20.8%) | 7 (25.9%) | 3 (30.0%) | 0.791 |
| Early graft revision <24 hours, n patients | 2 (8.3%) | 10 (37.0%) | 1 (10.0%) | 0.034 |
| Blood transfusions, n patients | 9 (37.5%) | 10 (37.0%) | 2 (20.0%) | 0.631 |
| Intubation >24 hours, n patients | 5 (20.8%) | 4 (14.8%) | 0 (0.0%) | 0.399 |
| Onset of Graft Infection | ||||
| Median time from graft implant to diagnosis of infection in days | 37 (IQR 11–131) | 40 (IQR 6–440) | 15 (IQR 6–26) | 0.538 |
| Early onset of infection (≤4 months after graft implant), n patients | 18 (75.0%) | 15 (55.6%) | 8 (80.0%) | 0.384 |
| Late onset of infection (>4 months after graft implant), n patients | 6 (25.0%) | 12 (44.4%) | 2 (20.0%) | 0.384 |
| Signs and Symptoms of Graft Infection | ||||
| Fever >38.5°C, n patients | 12 (50.0%) | 12 (44.4%) | 3 (30.0%) | 0.620 |
| Erythema, n patients | 3 (12.5%) | 1 (3.7%) | 5 (50.0%) | 0.003 |
| Wound discharge, n patients | 5 (20.8%) | 4 (14.8%) | 3 (30.0%) | 0.521 |
| Bleeding, n patients | 1 (4.2%) | 2 (7.4%) | 1 (10.0%) | 0.802 |
| Ischemia, n patients | 1 (4.2%) | 4 (14.8%) | 4 (40.0%) | 0.029 |
| Severe sepsis, n patients | 1 (4.2%) | 4 (14.8%) | 0 (0.0%) | 0.372 |
| Median white cell count as n×109/l | 11.3 (IQR 9.4–19.5) | 11.9 (IQR 8.3–23.5) | 9.9 (IQR 8.2–18.2) | 0.918 |
| Median C-reactive protein in mg/l | 102 (IQR 53–174) | 172 (IQR 107–261) | 95 (IQR 47–198) | 0.042 |
| A CT scan that showed fluid or air around the graft prosthesis, n patients | 20 (83.3%) | 13 (48.2%) | 2 (20.0%) | 0.001 |
| A positive blood culture**, n patients | 15 (62.5%) | 13 (48.1%) | 3 (30.0%) | 0.210 |
| A positive tissue culture††, n patients | 14 (58.3%) | 24 (88.9%) | 10 (100%) | 0.040 |
| Microbiological Characteristics: Patients with a identified microorganism ‡‡ | ||||
| Staphylococcus aureus §§, n | 4 (16.7%) | 6 (22.2%) | 4 (40.0%) | 0.362 |
| Coagulase-negative staphylococci, n | 8 (33.3%) | 3 (11.1%) | 5 (50.0%) | 0.030 |
| Propionibacterium acnes, n | 5 (20.8%) | 0 (0.0%) | 0 (0.0%) | 0.015 |
| Enterococcus spp., n | 5 (20.8%) | 11 (40.7%) | 2 (20.0%) | 0.257 |
| Escherichia coli, n | 0 (0.0%) | 4 (14.8%) | 0 (0.0%) | 0.068 |
| Pseudomonas aeruginosa, n | 1 (4.2%) | 1 (3.7%) | 1 (10.0%) | 0.717 |
| Enterobacter spp., n | 1 (4.2%) | 8 (29.6%) | 1 (10.0%) | 0.041 |
| Proteus mirabilis, n | 1 (4.2%) | 1 (3.7%) | 0 (0.0%) | 0.813 |
| Klebsiella spp., n | 0 (0.0%) | 2 (7.4%) | 0 (0.0%) | 0.272 |
| Stenotrophomonas maltophilia, n | 0 (0.0%) | 2 (7.4%) | 0 (0.0%) | 0.272 |
| Serratia marcescens, n | 0 (0.0%) | 0 (0.0%) | 1 (10.0%) | 0.075 |
| Morganella morganii, n | 0 (0.0%) | 1 (3.7%) | 0 (0.0%) | 0.527 |
| Anaerobic bacteria, n | 2 (8.3%) | 10 (37.0%) | 1 (10.0%) | 0.243 |
| Candida spp., n | 1 (4.2%) | 10 (37.0%) | 0 (0.0%) | 0.003 |
| Patients with polymicrobial infections, n | 5 (20.8%) | 18 (66.7%) | 4 (40.0%) | 0.004 |
PVGI = prosthetic vascular graft infection; IQR = interquartile range; BMI = body mass index; COPD = chronic obstructive pulmonary disease; ICU = intensive care unit; CT = computed tomography.
*Percentages and IQR values indicate relationship to the total number of patients within each respective group, not to the total number of patients included in the study.
A p-value ≤0.050 was considered significant.
Defined as the total number of patients with a medical history of peripheral arterial occlusive disease, coronary heart disease, or cerebrovascular disease.
Defined as an estimated glomerular filtration rate <60 ml/min/1.73 m2 at the time of PVGI diagnosis.
**There had been no blood cultures drawn for three patients with a thoracic PVGI and for three patients with a peripheral PVGI.
Defined as swabs or biopsies taken from the infected peri-graft areas whose cultures showed microbial growth.
Numbers (%) refer to patients with a specific pathogen isolated; multiple microorganisms per patient were possible. The causative microorganism was identified in blood cultures or in tissue cultures from surgical site for 60 (98.4%) of the 61 patients in the study.
One out of 14 Staphylococcus aureus isolates was methicillin-resistant.