Conventional culture diagnostics vs. multiplex PCR for the detection of causative agents of vascular graft infections - results of a single centre observational pilot study.

Background: Timely diagnosis of vascular graft infections is of major importance in vascular surgery. The detection of causative microorganisms is needed for specific medical treatment, but conventional culture is often slow, insensitive and inconclusive due to antibiotic pre-treatment. Detection of bacterial DNA by polymerase chain reaction (PCR) might bypass these problems. We hypothesised that multiplex PCR (mPCR) is feasible, fast and sensitive to detect causative microorganisms in vascular graft infections. Patients and methods: We performed a pilot observational prospective study comparing conventional culture and a commercial mPCR. Inclusion criteria were: confirmed graft infection, suspicious imaging, clinical suspicion, anastomotic aneurysm and repeated graft occlusion. Diagnostic methods were performed using identical samples. Time to result, microorganisms and antibiotic resistance in both groups were compared using Student's t-test or nonparametric tests. Results: 22 samples from 13 patients were assessed and 11 samples were negative for bacteria. Some showed multiple germs. In total, we found 15 different organisms. 13 samples matched, 9 had non-concordant results. Out of the mismatches 3 microorganisms identified in PCR were not detected by culture. Time to result with PCR was shorter (median 5 h vs. 72 h, p < 0.001) than with culture. No resistance genes were detected by mPCR, but conventional culture allowed susceptibility testing and revealed resistance in 5 samples. Conclusions: mPCR seems to be a feasible and quick tool to detect causes of vascular graft infections within 24 h and might be helpful in antibiotic pre-treated patients. The detection of antibiotic resistance with mPCR needs improvement for clinical practice.

Renal artery revascularization by using the Riolan anastomosis as feeding vessel in a patient with abdominal aortic coarctation due to fibromuscular dysplasia.

Fibromuscular dysplasia is a non-inflammatory, non-atherosclerotic vascular disease, occurring predominantly in younger females. A histologically heterogeneous group of fibroplasia without an inflammatory component causes arterial narrowing. It affects mostly one or both renal arteries, cervicocranial or visceral arteries, leading to hypertension, renal failure/renal infarction or stroke/transient ischaemic attack. We present the case of a young female patient with abdominal aortic coarctation, history of acute renal failure, and critical hypertension due to pseudo-occlusion of both renal arteries. We performed renal artery revascularization specifically by using the Riolan anastomosis as feeding vessel.

Dorsal (posterior) versus medial approach for the surgical repair of popliteal artery aneurysms.

The surgical approach-of-choice for the management of popliteal artery aneurysms (PAAs) remains controversial. We compared the results of the medial (MA) and dorsal (posterior) surgical approach (DA). Fifty patients (44 males/6 females; median age [range]: 59 [49-84] years) treated for 58 atherosclerotic PAAs were studied (MA: 29 PAAs; DA: 29 PAAs). The 3-year graft patency rates were higher after DA compared with MA (76% vs 52%, respectively), but the difference was not significant (P = .056). There were no differences between the 2 approaches in amputation, restenosis, reoperation, and wound infection rates. Dorsal approach and the MA may be alternative approaches with similar long-term results. Due to the controversial results reported so far, a meta-analysis may be necessary to establish the surgical approach-of-choice. Future studies should take into account additional factors, other than the surgical technique, when assessing outcome (eg, preoperative statin use, age, and emergency vs routine surgery).

Bilateral iliac artery dissection following severe complex unstable pelvic fracture.

The case of an 18-year-old polytrauma patient with a complete disruption of the right external iliac artery and a dissection of the left external iliac artery mainly caused by bilateral complex pelvic fractures type C, a subluxated horizontal fracture of the right acetabulum, and a transforaminal sacrum fracture is described.