Dissemination of Cephalosporin Resistance Genes between Escherichia coli Strains from Farm Animals and Humans by Specific Plasmid Lineages

Third-generation cephalosporins are a class of β-lactam antibiotics that are often used for the treatment of human infections caused by Gram-negative bacteria, especially Escherichia coli. Worryingly, the incidence of human infections caused by third-generation cephalosporin-resistant E. coli is increasing worldwide. Recent studies have suggested that these E. coli strains, and their antibiotic resistance genes, can spread from food-producing animals, via the food-chain, to humans. However, these studies used traditional typing methods, which may not have provided sufficient resolution to reliably assess the relatedness of these strains. We therefore used whole-genome sequencing (WGS) to study the relatedness of cephalosporin-resistant E. coli from humans, chicken meat, poultry and pigs. One strain collection included pairs of human and poultry-associated strains that had previously been considered to be identical based on Multi-Locus Sequence Typing, plasmid typing and antibiotic resistance gene sequencing. The second collection included isolates from farmers and their pigs. WGS analysis revealed considerable heterogeneity between human and poultry-associated isolates. The most closely related pairs of strains from both sources carried 1263 Single-Nucleotide Polymorphisms (SNPs) per Mbp core genome. In contrast, epidemiologically linked strains from humans and pigs differed by only 1.8 SNPs per Mbp core genome. WGS-based plasmid reconstructions revealed three distinct plasmid lineages (IncI1- and IncK-type) that carried cephalosporin resistance genes of the Extended-Spectrum Beta-Lactamase (ESBL)- and AmpC-types. The plasmid backbones within each lineage were virtually identical and were shared by genetically unrelated human and animal isolates. Plasmid reconstructions from short-read sequencing data were validated by long-read DNA sequencing for two strains. Our findings failed to demonstrate evidence for recent clonal transmission of cephalosporin-resistant E. coli strains from poultry to humans, as has been suggested based on traditional, low-resolution typing methods. Instead, our data suggest that cephalosporin resistance genes are mainly disseminated in animals and humans via distinct plasmids

ICAR: endoscopic skull‐base surgery

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Treatment of Intracranial Superfi cial Micro-AVMs: A Single Center Experience

Background: Surgery and embolization may both be considered in ruptured superficial micro-AVMs. However, surgery may be challenged by poor recognition of the lesion and embolization by difficulty in achieving complete obliteration and avoiding en passage feeders. Recent developments in AVM surgery and embolization techniques call for a reevaluation of these treatment options.Methods: Eight consecutive patients with superficial micro-AVMs are presented. All patients received an initial embolization attempt with either nBCA or ONYX. If complete obliteration was not obtained, either a second embolization or surgical resection was offered. At surgery, indocyanine green video angiography (ICG-VA) was used in all cases. Effectiveness and safety of all procedures were evaluated retrospectively. Functional outcome at 6 months was assessed by the modified Ranking Score (mRS).Results: Patients had a mean age of 52±17 years and all presented with hemorrhage. The mean nidus size was 4 mm, and was localized supratentorially in 5 cases and infratentorially in 3. Initial embolization was successful in 2 patients (25%). One patient underwent a second, unsuccessful, embolization attempt and 1 patient did not receive further treatment. Consequently, five patients underwent surgery, which was successful in four (80%). The unsuccessful case was successfully reoperated. The only two procedural complications were related to superselective embolization, but neither caused clinical sequelae. Mean clinical follow-up was 29 months (range, 4–75mo), with mRS 0 in 2, mRS 1 in 4 and mRS 3 in 2 cases.Conclusions: In a current case series, embolization of superficial micro-AVMs was associated with a lower success rate (25% vs 80%) than microsurgery and a higher procedural complication rate (minor complications: 22% vs 0%).</p

Recovery of motor deficit accompanying sciatica-subgroup analysis of a randomized controlled trial

BACKGROUND CONTEXT: In patients with sciatica due to a lumbar disc herniation, it is generally recommended to reserve surgical treatment for those who suffer from intolerable pain or those who demonstrate persistent symptoms after conservative management. Controversy exists about the necessity of early surgical intervention for those patients that have an additional motor deficit. PURPOSE: The aim of this study was to compare the recovery of motor deficit among patients receiving early surgery to those receiving prolonged conservative treatment. STUDY DESIGN: Subgroup analysis of a randomized controlled trial. PATIENT SAMPLE: This subgroup analysis focuses on 150 (53%) of 283 patients with sciatica due to a lumbar disc herniation and whose symptoms at baseline (before randomization) were accompanied by a motor deficit. OUTCOME MEASURES: Motor deficit was assessed through manual muscle testing and graded according to the Medical Research Council (MRC) scale. METHODS: In total, 150 patients with 6 to 12 weeks of sciatica due to a lumbar disc herniation and whose symptoms were accompanied by a moderate (MRC Grade 4) or severe (MRC Grade 3) motor deficit were randomly allocated to early surgery or prolonged conservative treatment. Repeated standardized neurologic examinations were performed at baseline and at 8, 26, and 52 weeks after randomization. This study was supported by a grant from the Netherlands Organization for Health Research and Development (ZonMW) and the Hoelen Foundation The Hague. RESULTS: Sciatica recovered among seven (10%) of the 70 patients assigned to early surgery before surgery could be performed, and of the 80 patients assigned to conservative treatment, 32 patients (40%) were treated surgically because of intolerable pain. Baseline severity of motor deficit was graded moderate in 84% of patients and severe in 16% of patients. Motor deficit recovered significantly faster among patients allocated to early surgery (p = .01), but the difference was no longer significant at 26 (p = .21) or 52 weeks (p = .92). At 1 year, complete recovery of motor deficit was found in 81% of patients allocated to early surgery and in 80% of patients allocated to prolonged conservative treatment. Perceived overall recovery of sciatica was directly related to the presence of an accompanying motor deficit. Severe motor deficit at baseline (odds ratio, 5.4; confidence interval, 1.7-17.4) and a lumbar disc herniation encompassing >= 25% of the cross-sectional area of the spinal canal (odds ratio, 6.4; confidence interval, 1.3-31.8) were the most important risk factors for persistent deficit at 1 year. CONCLUSIONS: Early surgery resulted in a faster recovery of motor deficit accompanying sciatica compared with prolonged conservative treatment but the difference was no longer significant during the final follow-up examination at 1 year. (C) 2014 Elsevier Inc. All rights reserved