Indium 111-labeled white blood cell scans after vascular prosthetic reconstruction

The clinical value of indium 111-labeled white blood cell (WBC) scanning done after vascular graft procedures was investigated to differentiate noninfectious postoperative inflammation associated with graft incorporation from early prosthetic graft infection. Indium 111-labeled WBC scans were initially obtained in 30 patients before discharge from the hospital and during the subsequent follow-up period (334 days). Fourteen of 30 patients (47%) had normal predischarge scans that included all 10 patients who had grafts confined to the abdomen and 4 of 20 patients (20%) who had grafts arising or terminating at the femoral arteries (p less than 0.05). Sixteen of 30 patients (53%) discharged with abnormal initial indium 111 WBC scans underwent serial scanning until the scan normalized or a graft complication developed. All of the 16 patients had grafts involving the groin region. Abnormal indium 111 uptake in the femoral region continued for a mean 114 days without the development of prosthetic graft infections. The sensitivity of indium 111-labeled WBC scans for detecting wound complications was 100%, whereas the specificity was 50%. Thus, the accuracy of the test was only 53%. We conclude that (1) abnormal indium 111 WBC scans are common after graft operations involving the groin region but are unusual after vascular procedures confined to the abdomen, and (2) in the absence of clinical suspicion, the indium 111-labeled WBC scan does not reliably predict prosthetic graft infection because of the low specificity of the test in the early postoperative period.     

Limitations of indium leukocyte imaging for the diagnosis of spine infections

The usefulness of indium-111 white blood cell (WBC) scintigraphy in the detection of spine sepsis was studied in 22 patients who had open or percutaneous biopsies for microbiologic diagnosis. The indium images in 18 patients with vertebral infection were falsely negative in 15 (83%) and truly positive in 3 (17%). All four patients with negative cultures and histology had true-negative scans. The indium-111 WBC imaging results yielded a sensitivity of 17%, a specificity of 100%, and an accuracy rate of 31%. Prior antibiotic therapy was correlated with a high incidence of false-negative scans and photon-deficient indium-111 WBC uptake. The usefulness of indium-111 WBC scintigraphy for the diagnosis of vertebral infection may be limited to those patients who have not been treated with antibiotics previously.     

Value of 111indium leukocyte scanning in febrile organ transplant patients

Immunosuppressed febrile organ transplant patients present a diagnostic and therapeutic dilemma since symptomatology is often altered by immunosuppression, which also masks the location of infection. Fifty 111indium leukocyte ( 111In WBC) scans were performed to determine their usefulness in the organ transplant patient. The results were compared with computerized tomography (CT) and gallium 67-citrate (Ga) scanning. Eleven patients received both 111In WBC and Ga scans; 22 received both 111In WBC and CT scans. Ten 111In WBC scans had subtraction of 99m Tc sulfur or albumin colloid for liver evaluation and four 111In WBC scans had subtraction of 99m Tc DMSA for kidney evaluation. The overall sensitivity and specificity for 111In WBC scans was 90% and 90%, respectively. Lung uptake was sensitive (89%) and specific (97%) for pulmonary infections, including bacterial, fungal and cytomegalovirus pneumonias. Renal graft uptake occurred in 15 cases (41%), all except 2 being due to rejection, pyelonephritis, urinary tract infections, or cytomegalovirus infections. Pyelonephritis and renal abscesses were diagnosed in 3 cases with 99m Tc DMSA subtraction. Perihepatic abscesses (2), and infected liver cysts (4) were diagnosed with 99m Tc sulfur or albumin colloid subtraction. There were five false-negative CT scans and three false-negative Ga scans. Therefore, when compared with 111In: sensitivity = 88% vs 64% (CT), specificity = 80% vs 86% (CT); and sensitivity = 111In 90% vs 67% (Ga), specificity = 100% for both 111In WBC and Ga scans.(ABSTRACT TRUNCATED AT 250 WORDS)     

Indium 111-labeled leukocyte scanning for detection of prosthetic vascular graft infection

Recent animal and human studies have suggested that positive indium 111-labeled leukocyte scans may help establish the diagnosis of vascular graft infection; however, there is little information available about the predictive value of both positive and negative leukocyte scans in larger groups of patients. In this study 31 indium 111 leukocyte scans were performed prior to definitive treatment in 21 patients with suspected vascular graft infections. Patients with more than one leukocyte scan performed had either anatomically distinct sites of infection or rescanning of a potentially infected site after definitive treatment. Scans were performed according to the method of Baker et al., attaching 500 muCi of indium 111 to leukocytes with imaging 24 hours later. All patients with positive scans underwent surgical exploration of the area of leukocyte accumulation, with documentation of purulence and culture of the graft. Patients with negative scans were treated as if scan results were indeterminate and underwent surgical exploration for usual clinical indications; if no exploration was performed, the patient was followed up closely for at least 1 year. Twelve of 12 positive scans showed purulence or culture evidence of infection with three different organisms; in 15 instances of negative scans, two operations were performed with one infection noted, whereas no patient without surgery has had a graft infection at 10 months follow-up. In addition to localizing graft infections, two scans demonstrated a nonvascular site of infection. Positive scans also helped determine the extent of infection along the graft, allowing better planning of the surgical procedure. These results indicate that indium 111-labeled leukocyte scans help document and localize prosthetic vascular graft infections.     

Detection of abdominal aortic graft infection: comparison of magnetic resonance imaging and indium-labeled white blood cell scanning

Infected abdominal aortic grafts rank as one of the most severe complications of vascular surgery, with high mortality and morbidity. The incidence of infection after prosthetic aortic reconstruction is 1-3%. Diagnosis of vascular graft infection can be occasionally difficult. Clinical manifestations and assessment of the extent of graft infection are usually nonspecific, and their detection by radiographic methods, such as computed tomography (CT), magnetic resonance imaging (MRI), and leukocyte -imaging, can be difficult. The purpose of this study was to evaluate the predictive value (PV) of indium-111-labeled white blood cell scanning (WBCS) and MRI in patients who were suspected of having intracavitary vascular graft infection (IGF). The study was done as a cross-control retrospective, single-center study. Fifty-eight In-111-labeled WBC scans and 59 MRIs were performed in suspected patients between January 1995 and January 2005. Among the 40 suspected patients, 35 cases of aorta graft infection were identified intraoperatively. The diagnosis of IGF was based on clinical signs, microbiological and histological examination, MRI and leukocyte imaging, and lack of graft incorporation with surrounding fluid observed intraoperatively. The positive PV (PPV) of MRI was 95% (95% confidence interval [CI] 84-105%) compared to In-111-labeled WBCS, which was 80% (95% CI 62-96%). The negative PV (NPV) of MRI was 80% (95% CI 68-92%) compared to 82% (95% CI 69-94%) for In-111-labeled WBCS. MRI showed a nonsignificant but better PPV for detecting IGF compared to In-111 leukocyte imaging. The NPVs for MRI and In-111-labeled WBCS were very near each other, with a very small advantage for In-111-WBCS. This comparison study suggested MRI as a primary diagnostic modality to investigate patients suspected of having aortic graft infections before In-111-labeled WBCS.     

The predictive value of indium-111 leukocyte scans in the diagnosis of infected total hip, knee, or resection arthroplasties

To evaluate the usefulness of the indium-111 scan in detecting actually or potentially infected total hip, knee, and resection arthroplasties, 153 scans were performed on 143 patients who underwent reoperation for a loose or painful total joint arthroplasty or a resection arthroplasty between 1990 and 1996. Scans were interpreted as infected, not infected, or equivocal by an experienced nuclear medicine radiologist. Patients were considered to be infected if they met any 2 of the following criteria: i) positive intraoperative cultures, ii) final permanent histologic section indicating acute inflammation, and iii) intraoperative findings of gross purulence within the joint. Twenty-six patients (17%) met the infection criteria at the time of reoperation. Indium scans were found to have a 77% sensitivity, 86% specificity, 54% and 95% positive and negative predictive values, and 84% accuracy for the prediction of infection. Of 6 equivocal scans, none were infected. The results of this study suggest limited indications for the use of the indium-111 scan in the evaluation of painful hip, knee, or resection arthroplasties. A negative indium scan may be helpful in suggesting the absence of infection in cases in which the diagnosis is not otherwise evident.     

Added value of SPECT/CT in patients suspected of having bone infection: preliminary results

AIM: We evaluated the contribution of SPECT/CT as an adjunct to combined three-phase bone scintigraphy (planar and SPECT) for diagnosing and localizing bone infection. Subsequently, the diagnostic performance of SPECT/CT was compared to visual fusion of SPECT with data of additional CT, X-ray, or MRI studies (SPECT + CT/X-ray/MRI). MATERIALS AND METHODS: Thirty-one patients suspected of bone infection, presenting pathological findings on triple-phase bone scintigraphy, underwent additional SPECT/CT. The SPECT/CT-technology combines the acquisition of SPECT and CT data with the same imaging device enabling perfect overlay of anatomical and functional images. (99m)Tc-DPD was used as radiopharmaceutical in all patients. For data analysis findings of bone scintigraphy (planar scans as well as SPECT) were categorized as positive, negative, or equivocal for the presence of osteomyelitis. In a second step, they were compared with SPECT/CT and SPECT + CT/X-ray/MRI with respect to localization and classification of lesions. Validation was achieved by surgery, biopsy, or by clinical follow up over at least 9 months including microbiological and radiological findings. RESULTS: Three-phase bone scan (incl. SPECT) correctly classified 7 lesions as positive and 11 lesions as negative for osteomyelitis. Six scans were interpreted false positive, two false negative, and five as equivocal. Rating the latter as positive for osteomyelitis, sensitivity of bone scan was (78%), specificity (50%). SPECT/CT was true positive in 7 patients, and true negative in 19. There were two false positive and two false negative findings, one scan was equivocal (sensitivity 78%, specificity 86%). Definition of anatomical localization of inflammatory foci was much easier by SPECT/CT due to better depiction of underlying anatomical details. SPECT + CT/X-ray/MRI yielded the highest sensitivity (100% compared to 78% of SPECT/CT), if equivocal findings (5/31 compared to 1/31 for SPECT/CT) are rated as true positive for osteomyelitis. Among radiological techniques, MRI (2 x FP) and CT (2 x FN) proved equal and expectedly superior to X-ray in delivering the correct diagnosis. CONCLUSION: SPECT/CT improves the diagnostic performance of three-phase bone scan for osteomyelitis by avoiding false positive or equivocal results. An additional benefit over visual fusion of SPECT with X-ray, CT, or MRI studies could not be confirmed in our study.     

Accuracy of FDG-PET–CT in the Diagnostic Work-up of Vascular Prosthetic Graft Infection

ObjectivesTo investigate the diagnostic accuracy of fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) compared with computed tomography (CT) scanning and added value of fused FDG-PET–CT in diagnosing vascular prosthetic graft infection.DesignProspective cohort study with retrospective analysis.MaterialsTwenty five patients with clinically suspected vascular prosthetic infection underwent CT and FDG-PET scanning.MethodsTwo nuclear medicine physicians assessed the FDG-PET scans; all CT scans were assessed by two radiologists. Fused FDG-PET/CT were judged by the radiologist and the nuclear medicine physician. The concordance between CT and FDG-PET and the inter-observer agreement between the different readers were investigated.ResultsFifteen patients had a proven infection by culture. Single FDG-PET had the best results (sensitivity 93%, specificity 70%, positive predictive value 82% and negative predictive value 88%). For CT, these values were 56%, 57%, 60% and 58%, respectively. Fused CT and FDG-PET imaging also showed high sensitivity and specificity rates and high positive and negative values. Inter-observer agreement for FDG-PET analysis was excellent (kappa = 1.00) and moderate for CT and fused FDG-PET–CT analysis (0.63 and 0.66, respectively).ConclusionFDG-PET scanning showed a better diagnostic accuracy than CT for the detection of vascular prosthetic infection. This study suggests that FDG-PET provides a useful tool in the work-up for diagnosis of vascular prosthetic graft infection.     

The specificity of technetium-labelled-leucocyte imaging of aortic grafts in the early postoperative period

Radio-labelled-leucocyte imaging is becoming accepted as the investigation of choice when infection of prosthetic arterial bypass grafts is suspected. However, alternative sources of inflammation, such as haematoma and, perhaps, the healing and incorporation of newly inserted bypass grafts, are potential causes of false positive results. This study examines the use of technetium-labelled-leucocyte imaging during the postoperative in-hospital period following aortic bypass surgery. Two labelled-leucocyte scans were carried out serially in 20 patients randomly allocated to receive either of two types of Dacron aortic graft in regular use. The earlier scans were undertaken at 2-5 days after surgery and only two of these scans were positive. None of the later scans, undertaken at 7-10 days after surgery, was positive. None of the patients had a graft injection as evidenced by clinical features, leucocyte counts, and C-reactive protein measurements. These results suggest that recent surgery does not in itself significantly reduce the specificity of technetium-labelled-leucocyte imaging.     

Vascular graft infection: the role of indium scanning

Infection of a prosthetic graft is one of the most feared complications of vascular surgery. The difficulties of accurate, objective diagnosis are well recognised. We have used III Indium labelled white blood cell scans (InWBC) in two groups: 9 control patients who underwent uncomplicated aortic aneurysm surgery, and 23 patients with suspected graft sepsis. In the control group there was one positive scan in a patient with an inflammatory aneurysm. In the suspected sepsis group, 11 patients subsequently has proven graft sepsis. Nine were correctly predicted by Indium scanning. Ten of 12 patients who did not have proven graft sepsis had negative scans. There was a total of 5 inflammatory aneurysms in the control and suspected sepsis groups, of whom two had positive scans. False positive scans were not present in the early postoperative period i patients without inflammatory aneurysms. In our experience Indium labelled WBC scanning for suspected graft sepsis has a accuracy of 83% a negative predictive value of 83% and a positive predictive value of 82%. These results suggest that Indium white cell labelling techniques which do not involve substantial cross-labelling of platelets are the best objective methods of establishing the presence or absence of graft sepsis.     

Value of quantitative cell count and amylase activity of peritoneal lavage fluid

From January 1974 through July 1979, 1,588 patients underwent diagnostic peritoneal lavage. The test had an accuracy of 98.6%, sensitivity of 94.3%, and specificity of 99.8%. It was true positive in 21.9%, false positive in 0.1%, false negative in 1.3%, and true negative in 76.6%. Fifty-nine patients from the true-positive group had grossly equivocal tests, but had positive lavage results based on quantitative cell count. Thus without cell count the test would have a sensitivity of 78.3%, accuracy of 94.8%, and specificity of 99.8. Eight patients had positive lavage based on WBC count but negative RBC count; all of these patients had bowel injuries. Measurement of lavage fluid amylase resulted in minimal or no improvement in the accuracy (0.06%), sensitivity (0.3%), or specificity (0.0%). Five of six patients with positive amylase levels but grossly negative tests had concomitant positive WBC count. The added cost of the amylase measurement is estimated to be $154,472. Peritoneal lavage has high accuracy, sensitivity, and specificity. Cell counts significantly improve sensitivity. Patients with a grossly equivocal test but with a positive cell count should undergo laparotomy. The lavage-fluid amylase measurement is costly and is of insignificantly yield.     

Graft-preserving treatment for vascular graft infected with Staphylococcus aureus with antibiotic-releasing porous apatite ceramic in the rabbit

OBJECTIVE: This study was undertaken to investigate whether infection of a vascular graft with Staphylococcus aureus can be treated in situ by applying antibiotic-loaded porous apatite ceramic, in a rabbit model. METHODS: Teicoplanin (TEIC) was loaded onto a beta-tricalcium phosphate (TCP) block, a type of porous apatite ceramic. The activity of TEIC released from the antibiotic-loaded TCP block was examined in vivo. A vascular graft was patched onto the abdominal aorta in 24 rabbits, and S aureus was applied directly on it. Seven days postoperatively, each rabbit underwent repeat laparotomy, and retroperitoneal abscess around the prosthetic vascular patch was debrided. Animals were divided into four groups of 6 rabbits each. In group 1 only debridement was carried out. In groups 2 and 3, solution containing 40 or 60 mg of TEIC, respectively, was applied to the prosthetic vascular patch. In group 4, an antibiotic-loaded TCP block (63 +/- 6.6 mg of TEIC) was placed around the graft. Three weeks after the second operation, the graft, the tissue around it, and arterial blood were collected and cultured. RESULTS: TEIC activity was maintained for 28 days in vivo. In group 1, bacterial cultures of the prosthetic vascular graft and the tissue around it were positive in 5 animals and negative in 1 animal (infection rate, 83%). In both groups 2 and 3, cultures were positive in 3 animals and negative in 3 animals (infection rate, 50%). In group 4, cultures were negative in all animals (infection rate, 0%). Blood cultures were negative in all animals. Infection rate in group 4 was significantly lower than that in group 1 (P =.03), and was also lower than that in groups 2 and 3, but the difference was not significant. CONCLUSIONS: Use of slow-release antibiotic loaded onto a TCP block, along with debridement, may control infection in vascular grafts in situ, averting the necessity to remove the graft.     

Indium 111 autologous tagged leukocytes in the diagnosis of intraperitoneal sepsis.

We report the results of a new test, indium oxine in 111 scanning, in the diagnosis of postoperative infection. Indium 111 was used to label autologous polymorphonuclear leukocytes, which when reinjected migrate to sites of infection, inflammation, or both. Standard scintigraphy localizes the labeled inflammatory cells at these sites. Sixty-six scans were performed in 43 surgical patients. Thirty-seven scans were categorized as true-positive; 19 scans were categorized as true-negative. Therefore, the accuracy rate was 85%. Two scans (3%) in one patient represented false-positive results. Two scans (3%) were positive for inflammation but there was no infection present; this group was denoted as equivocal. Six scans (9%) were false-negative; false-negative scans are more likely in old lesions with poor blood supply and in areas that overlap regions of normal uptake. The noninvasive nature of the test, high accuracy rate, and ease of administration make it a potentially useful tool in the diagnosis of postoperative infection.     

Pre-donation Assessment of Kidneys by Magnetic Resonance Angiography and Venography: Accuracy and Impact on Outcomes

Reports on the accuracy of magnetic resonance angiography (MRA) and magnetic resonance venography (MRV) in evaluating living donor renovasculature employ few patients or omit the consequences of inaccurate scans. We retrospectively compared intraoperative findings to MRA/MRV scans in 146 donor–recipient pairs. For detecting accessory arteries and early branching, MRA sensitivity was 57.6%, specificity 96.5%, false positive rate 3.5%, false negative rate 42.4%, positive predictive value 82.6%, negative predictive value 88.6% and overall accuracy 87.7%. By excluding clinically inconsequential accessory arteries, MRA sensitivity rose to 73.1%, specificity to 96.7% and overall accuracy to 92.5%. For MRVs, sensitivity was 56.2%, specificity 99%, false positive rate 1%, false negative rate 43.8%, positive predictive value 90%, negative predictive value 94.8% and accuracy 94.5%. Inaccurate scans were associated with prolonged donor and recipient operations and more frequently reconstructed arteries, but did not affect clinical outcomes. Because most missed accessory arteries are inconsequential, MRA is a useful, less invasive method for defining donor renovascular anatomy.     

111-In leukocyte scintigraphy in inflammatory diseases of the support and motor systems--initial results

Acute osteomyelitis and arthritis, soft tissue infections as well as reactivated chronic osteomyelitis and septic total hip endoprostheses show positive scans in 111-In-Acetylaceton-Leucocyte-Scintigraphy. Negative results are found in chronic osteomyelitis and nonbacterial inflammations as rheumatic and degenerative diseases of the skeleton. Accuracy for all studies was 86%, specificity 100% and sensitivity 66%. False negative scans findings occurred especially in soft tissue infections and acute spondylitis. There have been no false positive scans. Typical case reports are illustrated.     

New isotopic technique for detecting prosthetic arterial graft infection: 99mTc-hexametazime-labelled leucocyte imaging

Early and accurate detection of prosthetic arterial graft infection is important because this serious complication of vascular surgery carries high morbidity and mortality rates. This report describes the use of a new method of isotopic imaging to detect graft infection using 99mTc-hexametazime-labelled leucocytes. Seventeen patients with potentially infected arterial grafts were imaged in addition to routine investigations but were managed according to our normal surgical practice. 99mTc-imaging was positive in eight patients with proven graft infection and falsely positive in one patient with a groin haematoma (89 per cent specificity). There were no false negatives (100 per cent sensitivity) after an average follow-up of 6 months (range 3-9 months). This technique has proved a reliable and rapid method of confirming graft infection.     

Monitoring urinary amylase and pH in pancreas transplantation with urinary drainage in rats

Whole pancreas isografts or allografts (ACI donors, RT1a) with bladder drainage of exocrine secretions were performed in Lewis rats (RR1(1] with streptozotocin-induced diabetes. Urinary amylase, pH, and volume and serum glucose were measured daily. They were analyzed alone, or in combination, to determine patterns in deviations from normal values, from isograft control values, or from a posttransplant baseline in relation to rejection (defined as reversion of plasma glucose of greater than 200 mg/dl) in nonimmunosuppressed recipients. Also studied were the sensitivity and specificity by which such deviations predicted rejection. Functioning grafts were associated with increased urinary amylase and pH compared with normal or diabetic controls; urinary volume was less than that of diabetic rats, but greater than that of normal rats. In nonimmunosuppressed allograft recipients (n = 9), rejection occurred at a mean (+/- SD) of 7.78 +/- 0.44 days. Serum glucose rose to above normal (greater than 134 mg/dl) 1 day before rejection in 3 animals (sensitivity 33%, false negative rate 66%; false positive rate in 9 isograft recipients, 44%). Urinary volume dropped below 3 ml at a mean of 3.17 +/- 0.98 days (range 2-5 days) before rejection in 6 animals (sensitivity 66%, false negative rate 33%; false positive rate 0%). Urinary pH fell below 7.25 at a mean of 3.13 +/- 1.81 days (range 1-5 days) before rejection in 8 rats (sensitivity of 89%, false negative rate 11%; false positive rate 29%). Urinary amylase dropped from a posttransplant peak at a mean of 3.56 +/- 1.42 days (range 1-6 days) before rejection in 9 animals (sensitivity 100%, false negative rate 0%; false positive rate 43%), and dropped below 1500 units per 24 hr at a mean of 2.00 +/- 1.32 days (range 1-5 days) before rejection in 8 animals (sensitivity 89%, false negative rate 11%; false positive rate 0%). A drop in urinary amylase combined with a drop in urinary volume or pH occurred at a mean of 3.22 +/- 1.48 days (range 1-5 days) before rejection in 9 rats (sensitivity 100%, false negative rate 0%; false positive rate 0%). In a separate group of 10 allograft recipients, immunosuppression with prednisone and cyclosporine was begun concomitant with, or within 2 days of, the drop in urinary amylase from the peak value; rejection did not occur in 3 animals and was delayed to a mean of 12.0 +/- 5.0 days posttransplant in 7 animals (P less than .05 compared with the nonimmunosuppressed group).(ABSTRACT TRUNCATED AT 400 WORDS)     

The relevance of arterial wall microbiology to the treatment of prosthetic graft infections: graft infection vs. arterial infection

One potential, but poorly studied source for intraoperative contamination of vascular grafts is the native artery to which the prosthetic graft is attached. The purpose of this study was to analyze the relationship between arterial wall microbiology and graft infection. Between July 1, 1981, and March 31, 1982, arterial specimens were cultured from 88 (30%) of 298 patients undergoing clean, elective arterial reconstructive procedures. Control cultures were obtained from adjacent adipose or lymph node tissue. Positive cultures were obtained from 38 of 88 (43%) of the arterial walls cultured but from none of the control cultures (0 of 20) (p less than 0.001). The most common organism cultured was Staphylococcus epidermidis (27 of 38; 71%). Our overall graft infection rate since January 1, 1981, is 0.9% (3 of 335). All three graft infections occurred in patients with positive arterial cultures. Arterial and graft cultures were also obtained from 20 patients treated for 22 graft infections over the past 13 years. Organisms recovered included staphylococcal species (36%), enteric organisms (46%), and mixtures of the two (18%). These patients with culture-positive graft infections were divided retrospectively into two groups: those with positive and those with negative arterial cultures. Positive arterial cultures were associated with suture line disruption in 8 of 14 cases (57%), but there were no arterial disruptions in patients with negative cultures (0 of 8) (p less than 0.01). These data document a significant correlation between positive arterial wall cultures and subsequent prosthetic infection and also suggest that infection involving the arterial wall is a major determinant of the morbidity and mortality associated with the treatment of prosthetic graft sepsis.     

Aortic graft infections: treatment with arterial allograft

Since its reintroduction by Kieffer in 1991, many authors have used arterial allografts for surgical management of vascular prosthetic graft infection. During a decade, 25 patients with aortic graft infection were treated using in situ revascularization with arterial allograft. There were 23 male and 2 female patients of mean age of 65.7 +/- 8.8 years (range, 43-78). Antibiotic therapy was administered for a mean time of 26 +/- 5 days (range, 21-45) in the postoperative period. The mean follow-up time was 2.3 +/- 3 years (range, 22 days-8.7 years). The mean in-hospital postoperative stay was 29.6 +/- 14 days (range, 9-68). An aorto-enteric fistula (AEF) was present in 11 patients (44%), producing gastrointestinal bleeding. The overall mortality rate was 13 of 23 (56.5%) patients. The allograft-related mortality rate was 5 of 23 (22%). The overall allograft-complicated patient rate was 15 of 23 (65%); we observed 18 allograft ruptures in 12 patients and 8 allograft thromboses in 6 patients. The overall amputation rate was 8.7% (2 of 23). Age of the recipient older than 69 years (P = .02), positive preoperative marked-leukocyte scanning (P = .04), and persistent postoperative leukocytosis (P = .03) were significant variables associated with an increased risk of allograft-related complications. The use of arterial allografts for aortic graft infections represents an interesting alternative for the treatment of graft infection. Nevertheless, there are some problems related to the durability of this type of graft, which can still be considered as a "bridge transplant."     

InterGard silver bifurcated graft: features and results of a multicenter clinical study

OBJECTIVES: Recent research in vascular surgery has focused on development of infection-resistant prosthetic grafts. This article describes the results of a multicenter study to evaluate safety, patency, and infection rates after implantation of the InterGard Silver bifurcated polyester graft coated with collagen and silver. METHODS: Between October 2000 and February 2002, 289 consecutive patients were implanted with a collagen and silver acetate-coated polyester bifurcated graft at 16 French vascular surgery centers. Mean patient age was 65.3 +/- 10.9 years. The indication for prosthetic bypass was aortic aneurysm in 160 patients (55.4%) and symptomatic aortoiliac occlusive disease in 129 (44.6%). All but four patients received prophylactic antibiotic therapy. Patency was assessed at 30 days, 1 year, 2 years, and 3 years, primarily by duplex scan. RESULTS: Two patients (0.7%) died during the first 30 days. Median duration of hospitalization was 11 days. The Kaplan-Meier survival rate at 3 years was 85.7% +/- 4.1%. Primary and secondary patency rates at 3 years were 94.9% +/- 2.6% and 97.5% +/- 1.8%. Thrombectomy was performed successfully in seven patients, and a major amputation was required in two patients with patent grafts. Postoperative complications, including 39 nosocomial infections, were observed in 107 patients (37.0%). Eleven patients presented with 12 wound infections that were classified Szilagyi grade I in eight cases, grade II in two cases, and grade III with graft infection in two cases (0.7%). Among the 149 patients undergoing aortofemoral bypass, eight (5.4%) presented with wound infection, including two graft infections (1.3%). Among the 140 patients undergoing aortoiliac bypass, only three patients (2.1%) presented wound infection and none with graft infection (P = .15). Three (16.7%) of 18 patients who had undergone previous femoral revascularization and eight (3%) of 271 patients without previous femoral revascularization presented with wound infection. This difference was statistically significant (P = .03), with a relative risk of 5.6 (95% confidence interval [CI], 1.6 to 19.5). Five (11.9%) of 42 diabetic patients and six (2.4%) of 247 nondiabetic patients presented with wound infection. This difference was also statistically significant (P = .01), with a relative risk of 3.4 (95% CI, 1.7 to 6.9). Lymphorrhea or lymphocele developed in the groin of 25 patients (8.6%) with negative culture. CONCLUSION: This multicenter prospective study shows that the InterGard Silver graft is safe with no side effects. The primary patency rate was excellent, and the graft infection rate was low, despite a high incidence of nosocomial infections.