Multiplex microarray PCR Unyvero BCU system to accelerate relevant antimicrobial treatment in polymicrobial bloodstream infection.

PURPOSE: To evaluate the performance of a rapid multiplex microarray-based method (Unyvero BCU system, BCU) to identify microorganisms and detect antimicrobial resistance directly from positive blood culture (BC) bottles with polymicrobial growth, and to assess relevance of information provided for timely guidance of polymicrobial bloodstream infection treatment. METHODS: Accuracy, time-to-actionable results and potential impact of BCU on antimicrobial treatment were compared with those of standard of care during a prospective study for the sample analysis (November 2017-November 2018) and a retrospective study for the clinical data analysis and the time-to-result analysis. The study was complemented with an experimental study, based on spiked blood cultures to assess the ability of the method to detect antimicrobial resistance genes. RESULTS: Sixty-five clinical polymicrobial BC samples (163 total microorganisms) and 30 simulated polymicrobial BC samples (60 strains) were included. BCU reported 84.6% samples as polymicrobial, correctly identified all the bacteria of the mix for 72.3% samples (47/65) and detected bacteria that were missed by the conventional culture for 13.8% samples. All identifications and antimicrobial resistances were accurately detected for 61.5% (40/65) samples. Limitations concerned the detection of anaerobes, enterococci and enterobacterial susceptibility to third generation cephalosporins. BCU results would have guided antimicrobial treatment for 50.8% of the cases (33/65) in a timely and relevant manner, had no impact for 27.7% (18/65) and been misleading for 18.5% (12/65). CONCLUSIONS: Despite some limitations, the Unyvero BCU system is a rapid and reliable method for polymicrobial BC sample analysis.

Six weeks antibiotic therapy for all bone infections: results of a cohort study.

There is no consensus on the antibiotic therapy for bone infection due to the heterogeneous spectrum of diseases. Most authors suggest different durations of treatment based on pathophysiological considerations. However, adverse effects are related, at least in part, to the duration of treatment. We, therefore, investigated a 6 weeks antibiotic combination therapy for all cases of bone infection. Herewith, we report the results of this therapeutic approach. This is a cohort study including all patients presenting with bone infection, regardless of the mechanism involved. The diagnosis was based on bone biopsy obtained through invasive procedures. Chronic bone infection was defined as a history of disease of over 1 month duration. The duration of clinical follow-up following treatment discontinuation was at least 6 months. Cured bone infection was defined as the absence of relapse after antibiotic discontinuation. One hundred and eighteen patients were included between July 2005 and March 2009; 61 presented with bone infection following prosthetic implant (52%) and the 57 remaining patients had bone infection without foreign material (48%). Surgery was required for 80 patients (68%). Microbial agents were identified in 116/118 patients, with 24 patients presenting with polymicrobial sepsis (20%). The mean duration of antibiotic treatment was 42 +/- 0.2 days and the mean clinical follow-up was 27 +/- 14 months. The treatment success rate was 91.5% (108/118). Six weeks of antimicrobial therapy appears to be effective for nearly all bone infections, regardless of the pathophysiology. These results encourage us to pursue attempts to simplify the management of bone infection without obvious prejudice to the patient.

Modulation of the renal effects of contrast media by endothelium-derived nitric oxide in the rat.

RATIONALE AND OBJECTIVES: A possible involvement of endothelium derived relaxing nitric oxide (NO) in the pathogenesis of iodinated contrast media (CM)-induced nephrotoxicity was investigated in the rat. METHODS: Male rats (6 to 12 per group) were uninephrectomized. Six days later, the aorta was clamped above the renal artery and a low-osmolar contrast medium (CM), ioxaglate, was injected (1 mL/min; 3 minutes) via an aortic puncture in the single remaining kidney. Contrast medium was injected with or without the NO-synthase inhibitor L-NAME (100 mg/kg intravenously [i.v.] 5 minutes before CM). One group received L-Arginine, the physiological precursor of NO (100 mg/kg i.v.), 5 minutes before L-NAME. Phenylephrine (300 micrograms/kg; 30 min) was used as a vasoconstrictive NO-independent control. The effects of iohexol, another low-osmolar CM, on creatinine clearance (CrCl) were also studied with and without pretreatment with L-NAME. A control group was subjected to a 3-minute renal ischemia only. Creatinine clearance and urinary N-acetyl-beta-D-glucosaminidase (NAG) excretion were determined before, and 24 and 48 hours after CM administration. Blinded histologic analysis was carried out after completion of the study. RESULTS: When administered alone, neither L-NAME nor L-arginine modified CrCl. Ioxaglate mildly but significantly decreased CrCl at 24 hours (-26.5% of preinjection value). This was similar to the effect observed in the control group subjected to ischemia only. When associated with L-NAME, ioxaglate markedly decreased CrCl (-58 + 11% at 24 hours, P < .05 vs. ioxaglate alone). A similar interaction was noted in the case of iohexol. L-NAME also markedly increased ioxaglate-induced urinary NAG excretion. Phenylephrine had a similar impact on renal function. L-arginine pretreatment reduced the increase in serum creatinine induced by L-NAME+ioxaglate (68 + 17 mumol/L vs. 175 + 59 mumol/L for L-NAME+ioxaglate; P < .05) and urinary NAG excretion. Ioxaglate alone induced only tubular epithelial vacuolization. When associated with L-NAME, this CM induced tubular and vascular lesions, as well as necrosis in the outer medulla. Such histologic effects were clearly inhibited by L-arginine. CONCLUSION: These data indicate that L-NAME, a specific inhibitor of NO-synthase, and phenylephrine, accentuate the nephrotoxicity of CM in the rat. This is consistent with results from the literature showing that CM-toxicity is enhanced by renal ischemia.

[Systematic use of 4 French catheters for left heart catheterization and coronary angiographies]. / Utilisation systématique des sondes 4 French pour la réalisation des cathétérismes gauches et des coronarographies.

The feasibility of left heart catheterisation and coronary angiography using small calibre 4 French catheters was assessed in a prospective register of 355 consecutive patients. The average age was 64 +/- 10 years: 21% were women. The indications were: evaluation of coronary artery disease (279 patients), control of bypass graft patency (38 patients including 34 internal mammary artery grafts), 26 valvular lesions (including 15 aortic stenoses) and 12 cardiomyopathies. In 20.5% of cases, the catheterisation was performed on an out-patient basis. The catheters used for coronary opacification were Cordis Pigtail and Amplatz; mammary, multipurpose and right Judkins were used occasionally. The operators used on average 2.14 catheters, without difficulty in 13% of cases. A larger catheter was not required in any of the cases. There were no complications. The angiograms were estimated to be of good quality in 96% of cases. With the exception of patients undergoing immediate angioplasty and 9 patients with severe hypertension or anticoagulant therapy, the patients did not require compressive dressings on the puncture site and could be mobilised early. There were no local complications at the puncture site. The results of this study suggest that 4 F catheters can be used systematically for left heart catheterisation with safety. A short period of training is required after which good quality angiograms can be obtained without technical problems. Compressive dressings are not necessary after this type of investigation.

Six French sheathless coronary angioplasty using a novel technique to introduce the guiding catheter: the INTRUC, a preliminary retrospective study.

This registry describes our preliminary experience with a novel introducing-catheter allowing direct percutaneous introduction of the 6F guiding catheter (G-C), minimizing the puncture size, preventing vessel scraping, and improving the pushability and torque response of the G-C. In 1995, 203 patients had sheathless PTCA, using this device. Eighty-five percent were male. Mean age was 65+/-10 years. Thirty-nine percent had stable angina, 35% unstable angina, 7% evolving infarction, and 19% recent infarction. Two hundred fifty-six lesions were treated (1.26/patient). One hundred eight patients (52%) received one (85%) or more than one (15%) stent. The procedural success rate was 98%. Mean coronary stenosis was 82+/-10% and decreased to 20+/-15% after PTCA. No major complication occurred. The guiding catheter was immediately removed in 95% of patients, despite heparinization. No patient required surgery or blood transfusion for vascular complications, and only 7 had minor local complications (3.5%). Sheathless angioplasty provides no technical difficulties and has the same safety and quality as conventional angioplasty using a sheath. Immediate removal of the guiding catheter, without keeping vascular access, has no deleterious effect, allows early mobilization, and may limit the risk of vascular complications.

Comparison of 6F with 7F and 8F guiding catheters for elective coronary angioplasty: results of a prospective, multicenter, randomized trial.

A group of 460 patients was considered in our prospective study of assessment of the efficiency and safety of 6F (internal diameter 0.062 inches) guiding catheters to perform elective percutaneous coronary angioplasty by the femoral approach by using conventional balloon systems. The patients were randomly assigned either a 6F guiding catheter (first group, n = 231; 247 coronary lesions), or a 7F or 8F guiding catheter (second group, n = 229; 252 coronary lesions). The exclusion criteria were the ongoing myocardial infarction, the marked reduction of left ventricular function, and the decision to treat the lesion with a device not fitting the 6F guiding catheter. The angioplasty success rates (87% in the 6F group vs 88% in the 7F or 8F group) and the stent implantation rates (21% vs 25%) were similar in both groups. The ischemic complication rates (death, 2 vs 1 ) were also similar. The incidence of the femoral complications was significantly less important in the 6F group than in the 7/8F group (13.8% vs 23.5%; p < 0.01). Significant differences also were noted for the procedural time (36 +/- 22 vs 41 +/- 28 min; p < 0.01), the fluoroscopy time (11 +/- 10 vs 14 +/- 4 min; p < 0.05), the volume of contrast injected (136 +/- 68 ml vs 168 +/- 95 ml; p < 0.0001), and the time of femoral compression after the introducer sheath removal (11.7 +/- 9 vs 14.1 +/- 12 min; p < 0.01). Our data suggest that 6F guiding catheters for elective coronary angioplasty are more effective than are the larger diameter catheters. Besides a significant decrease of vascular complications, angioplasty with a 6F guiding catheter reduces the procedural time and the amount of contrast.