Late Dacron Patch Inflammatory Reaction after Carotid Endarterectomy.

OBJECTIVE: The aim was to analyse the incidence and presentation of carotid patch inflammatory reactions following carotid endarterectomy (CEA). METHODS: This was a cohort study using a prospectively maintained database. All patients who underwent elective CEA at a tertiary vascular centre between 2002 and 2016 were included. Computed tomography scan angiogram, duplex scan, and leucocyte scintigraphy were used to assess patients with suspected inflammatory patch complications. Re-intervention procedures and outcomes were noted. Histopathology and organisms cultured from the harvested material during re-intervention were assessed. RESULTS: During the study period, 633 patients underwent elective CEA. Fifty-one underwent eversion endarterectomy: 111 did not require a patch, whereas 471 patients had a patch repair. Four hundred and twenty eight had a Dacron patch repair and 43 a biological patch. Eight patients returned with late Dacron patch inflammatory complications (1.3% of all CEA and 1.9% of Dacron patch closures) after a period ranging from 18 months to 7 years (mean 4.1 ± 2.1 years). Seven of the eight patients underwent surgical re-intervention, and the eighth patient was deemed high surgical risk. One patient underwent a vein bypass, three had vein patch repair, one required internal carotid artery (ICA) ligation after patch excision, and two were managed by debridement, with omohyoid and sternomastoid muscle covering of the patch. The patient who required ICA ligation suffered a fatal stroke. The remaining patients had a satisfactory outcome. All patients showed evidence of foreign body reaction in pathological examination with no pathological organism cultured from swabs or tissue harvested during surgery. CONCLUSION: Late wound complications after CEA may be related to inflammatory reaction of the Dacron patch rather than infection. Infection should be excluded first. Reconstruction with vein is effective. However, debridement with sternomastoid and omohyoid muscle covering of the patch may be considered in high risk patients after exclusion of infection with regular follow-up.

Early Results of Brachial Arterio-Arterial Prosthetic Loop (AAPL) for Hemodialysis.

BACKGROUND: Vascular access has always been the Achilles heel of hemodialysis. Advances in health care have brought forward patients requiring treatment who have no veins suitable for creation of arteriovenous fistula (AVF) or insertion of central venous catheters. Use of an artery as permanent vascular access has been reported by many authors. This study reports brachial AAPL as an efficient and safe access for hemodialysis patients with central venous occlusion. METHODS: Between January 2011 and December 2014, 35 brachial arterio-arterial prosthetic loops (AAPL) were created. The age of patients ranged between 27 and 72 years, with a mean age of 52.8 years. RESULTS: The primary patency rates were 87.9%, 70.4%, and 38.8% at 12, 24, and 36 months, respectively. The secondary patency was 90.7%, 80.3%, and 67.6% at 12, 24, and 36 months, respectively, after successful thrombectomy in seven cases. CONCLUSION: Mid-term follow-up results demonstrate patency rates comparable with those of the synthetic AVF. The rate of complications, although slightly higher than that with traditional synthetic AVF, is still acceptable in this population with no option for access.

Secondary aortoduodenal fistula following endovascular repair of inflammatory abdominal aortic aneurysm due to Streptococcus anginosus infection: A case report and literature review.

INTRODUCTION: Aortoenteric fistula is a rare but very serious complication of both surgical and endovascular abdominal aortic reconstruction. Since the advent of endovascular abdominal aortic aneurysm repair (EVAR), 20 cases of aortoduodenal fistula associated with aortic stent grafts have been reported.(1) However, only a handful has been reported following inflammatory abdominal aortic aneurysm repair. It most commonly presents with bleeding, usually from the upper gastro-intestinal tract. With recent advances in the screening, diagnosis and management of abdominal aortic aneurysms either surgically or through an endovascular approach, the diagnosis of an aortoduodenal fistula in patients with gastro-intestinal bleeding must be suspected and excluded. PRESENTATION OF CASE: We describe a case of secondary aortoduodenal fistula that occurred two and a half years following endovascular stent graft repair of an inflammatory abdominal aortic aneurysm. We also outline the emergency correction plan and the attempts at repair. DISCUSSION: This case defies the general concept that patients with inflammatory abdominal aortic aneurysms are relatively immune to rupture. Although the presence of a peri-aneurysm thick inflammatory membrane decreases the possibility of rupture, these patients are more susceptible to other related complications such as aorto-enteric and aorto-caval fistulas.(2) This case also demonstrates the peculiar presence of Streptococcus anginosus as the pathological organism leading to graft infection and subsequent fistula, as opposed to enterococci which are often found in endograft infection. CONCLUSION: Aorto-enteric fistulas are associated with a grave prognosis. Early diagnosis is crucial and extra vigilance should be taken in cases of inflammatory AAA.

Malignant transformation of human fibroblasts by ionizing radiation.

As one step in developing an assay for quantifying the induction of malignant transformation of human cells by ionizing radiation, we exposed cells from a non-tumorigenic, infinite life span, near-diploid fibroblast strain MSU-1.1 to 4.35 Gy 60Co radiation and assayed them for focus formation. The mean frequency of foci in the irradiated population was 6 x 10(-7) cells assayed. No foci were found in the control cells. Of four focus-derived cell strains studied in detail, two produced malignant tumours within 3-7 weeks. The other two did not produce tumours during the 12-month period of study. The tumours from one strain were classified as sarcomas composed exclusively of spindle-shaped cells. Tumours from the other strain were sarcomas consisting of a mixed population of round and spindle cells. Immunoprecipitation analysis of the status of the p53 gene in the focus-derived strains, using a mutant-specific anti-body (Pab240) and an antibody that recognizes both mutant and wild-type p53 protein (Pab421), showed that the tumorigenic strains were completely devoid of p53 protein. One non-tumorigenic strain expressed wild-type p53 protein, and the other expressed a lower molecular weight form of the protein. Karyotypic analysis showed that the tumour-derived cells from one tumorigenic strain had lost one copy of chromosome 6, 14, 16 and 17. The tumour-derived cells from the second strain had lost one copy of chromosome 7, 13, 14 and 17 and part of chromosome 6, as well as part of the other copy of chromosome 7 and 17. These results suggest that the common loss of one copy of chromosome 14, 17 and part of 6 plays a causal role in the malignant transformation of these cells. Furthermore, the results indicate that it will be possible to develop a system that uses near-diploid human fibroblasts to quantify radiation-induced malignant transformation.

Ivermectin uptake and distribution in the plasma and tissue of Sudanese and Mexican patients infected with Onchocerca volvulus.

Ten Sudanese patients with Onchocerca volvulus infection were treated with a single oral dose of 150 micrograms/kg of ivermectin. Plasma samples were collected before treatment, 0.5, 1, 3, 4, 6, 12 hours and 1, 2, 3, 7, and 30 days. Four patients were selected for nodulectomies and skin biopsies at 6, 18 and 30 hours and 3 days post treatment. Using these samples O. volvulus worm fragments were dissected free of host nodular tissues for ivermectin extraction. Ivermectin was present in the nodular tissue at 6 hr and persisted for 3 days. It was also detected in an individual worm tissue extract at a concentration similar to the nodule, but in subcutaneous fascial tissue higher concentrations were sometimes found. Ivermectin was detected by radioimmunoassay in the plasma of all patients at 1 hr and peak concentrations were reached in an average of 5.6 hr. The drug persisted at detectable levels for 7 days in 70% of the studied patients. Plasma samples were also collected from 16 treated Mexican onchocerciasis patients before ivermectin treatment and 4 hr treatment and from six individuals who served as controls. The Mexican patients had concentrations of ivermectin in their plasma similar to those in the Sudanese patients.