[Glycopeptide-resistant Enterococcus outbreak in an ICU with simultaneous circulation of two different clones]

AIM OF THE STUDY

To describe specific difficulties to control a glycopeptide-resistant Enterococcus (GRE) outbreak occurring in an intensive care unit (ICU) during a regional epidemy.

PATIENTS AND METHODS

Following identification of a GRE clinical isolate in ICU, systematic screening was performed on admission and then weekly, by anal swabs. GRE carriers were isolated according to two processes: first (week [W] 2-W8), cohorting of carriers in a dedicated sector of the ICU, with dedicated HCW; this required closing four of the 16 ICU beds. Second (W8-W29), a specific unit was created outside the ICU. VanA-genotypes and pulsed-field gel electrophoresis (PFGE) profiles were analyzed.

RESULTS

During the first outbreak period (102 rectal swabs), two patients were found colonized at admission: the index case transferred from Nancy hospital, carrier of the Nancy epidemy PFGE profile strain, and one patient from the haemodialysis unit, carrier of a GRE strain presenting a different PFGE profile called the Thionville strain. Seven patients were newly identified as GRE colonized (2 by the Nancy strain and 5 by the Thionville strain). Defective running of the ICU was noted. During the second period (442 samples), six ICU patients were found colonized, including four at admission. No other case was identified in 16 weeks. Outbreak extension to other hospital units was checked at W19. The Thionville strain was not found in other regional hospitals.

CONCLUSION

ICUs concentrate GRE colonization risk. This study demonstrates interest of PFGE. These low virulence bacteria have few direct pathological consequences, but they cause organizational problems in ICUs.

Collective atomic recoil laser as a synchronization transition

We consider here a model previously introduced to describe the collective behavior of an ensemble of cold atoms interacting with a coherent electromagnetic field. The atomic motion along the self-generated spatially periodic force field can be interpreted as the rotation of a phase oscillator. This suggests a relationship with synchronization transitions occurring in globally coupled rotators. In fact, we show that whenever the field dynamics can be adiabatically eliminated, the model reduces to a self-consistent equation for the probability distribution of the atomic "phases." In this limit, there exists a formal equivalence with the Kuramoto model, though with important differences in the self-consistency conditions. Depending on the field-cavity detuning, we show that the onset of synchronized behavior may occur through either a first- or second-order phase transition. Furthermore, we find a secondary threshold, above which a periodic self-pulsing regime sets in, that is immediately followed by the unlocking of the forward-field frequency. At yet higher, but still experimentally meaningful, input intensities, irregular, chaotic oscillations may eventually appear. Finally, we derive a simpler model, involving only five scalar variables, which is able to reproduce the entire phenomenology exhibited by the original model.

Management of recurrent varices at the popliteal fossa after surgical treatment

Objectives

To analyze prevalence, incidence mechanisms, physiopathology, investigations, treatment techniques and results of recurrent varices at the popliteal fossa after surgery.

Methods

Published literature was analyzed as personal experience.

Results

Recurrent varices after surgery at the popliteal fossa are much less frequent than at the sapheno-femoral junction because the short saphenous vein is less often the site of incompetence and treated by surgery. Precise prevalence and incidence is unknown. An analysis of recurrences at the popliteal fossa revealed three causes: Incomplete division of the sapheno-popliteal junction (SPJ) at the terminal valve, which was incompetent at the initial surgery. The persisting reflux fills tributaries still connected to the saphenous stump; Neovascularization reconnects the popliteal vein to the superficial network with new vessels, which are valveless; Because the initial diagnoses is wrong and the incompetence involves the other veins of the popliteal fossa or arises from pelvic veins, which had not been recognized. Duplex scanning (DS) should identify the various sites of reflux and give precise anatomical and haemodynamic data. Treatment methods after recurrence at the popliteal fossa are repeat surgery, sclerotherapy or pelvic vein embolization when identified as the cause. Results provided by these different methods were analysed.

Conclusions

At present, no randomized control has given grade 1A, 1B or 2A, 2B recommendations. We recommend that ultrasound-guided foam sclerotherapy should be the treatment of choice unless DS shows an incompetent stump at the SPJ with a gross reflux filling the venous network.

[1-benzylpiperazine (BZP) and 1-(3-trifluorométhylphényl)pipérazine (TFMPP): emergence of two agents which lead to misuse]

1-benzylpiperazine (BZP) and 1-(3-trifluoromethylphenyl)piperazine (TFMPP) are psychoactive agents which have become available on the illicit drug market in France since 2006. These compounds are employed for their stimulating, enacting, and "recreational" properties. The combination of BZP and TFMPP enables drug users to reproduce the domaminergic and serotoninergic components of amphetamine derivatives. Intoxication can be life threatening for BZP. This compound has been detected, in association with other psychoactive agents with similar action, in several fatal cases. In addition, there is a potential risk of addiction, confirmed in animal models. The toxicity of TFMPP appears to be weaker with no apparent risk of addiction. There is however a risk of serious psychiatric manifestations and serotoninergic syndrome. There are certain national regulations, but to date no international regulations have been developed for BZP and TFMPP. In the European Union, BZP is now being monitored in compliance with the 10 May 2005 decision of the Commision on information sharing, risk evaluation, and control relative to new psychoactive agents.

Increased white matter connectivity in euthymic bipolar patients: diffusion tensor tractography between the subgenual cingulate and the amygdalo-hippocampal complex

Bipolar disorder has been associated with anatomical as well as functional abnormalities in a brain network that mediates normal and impaired emotion regulation. Previous brain imaging studies have highlighted the subgenual cingulate (SC) and the amygdalo-hippocampal (AH) complex as core regions of this network. Thus we investigated white matter (WM) fiber tracts between the SC and the AH region, the uncinate fasciculus, as well as between two control regions (pons and cerebellum), using diffusion tensor imaging tractography in 16 euthymic bipolar patients (BP) and 16 sex-, age- and handedness-matched controls. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) of the reconstructed fiber bundle and the number of virtual reconstructed fibers were compared between groups. The tractography results revealed a significantly increased number of reconstructed fibers between the left SC and left AH in BP as compared to healthy controls. FA and ADC of the reconstructed fiber tract did not differ significantly between the groups. Furthermore, no significant group differences were observed neither for reconstructed fiber tracts between the right SC and right AH nor between the control regions. The present results suggest an altered WM pathway between the left SC and AH region and thus extend previous findings of anatomical and functional modifications in these structures in BP.

Improvements of solid-core photonic bandgap fibers by means of interstitial air holes

We report the fabrication, characterization and modeling of a solid-core photonic bandgap fiber with interstitial air holes between the cladding rods. The presence of these interstitial air holes leads to a great improvement of optical properties for this kind of fiber. Particularly, we demonstrate that confinement losses and bend sensitivity are substantially reduced. Our experimental results for this new solution are well supported by numerical results.

[Recurrent varices at the groin and popliteal fossa after surgical treatment]

Patients who undergo surgery involving the groin and the popliteal fossa often develop recurrent varices which require careful management. Several surveys using various classification systems have estimated the prevalence of recurrent varices after groin and popliteal surgery. Patients may seek medical care for various reasons: unsightly recurrent varicose veins, vein-related symptoms, appearance of cutaneous or subcutaneous changes, concerns about the health risk related to their veins or limitation of activity. Recurrent varices may also be found at routine follow-up examinations. An analysis of recurrence at this location reveals three main mechanisms: incomplete resection of the saphenofemoral or saphenopopliteal junctions in patients with an initially incompetent terminal valve. The persisting reflux feeds the tributaries connected at the saphenous stump; the second mechanism is related to neovascularisation that reconnects the deep venous system with the superficial network; the neo-veins are valveless. This phenomenon appears to be more frequent when the resection of the saphenous vein ending has been complete; the third mechanism is due to a tactical error; the refluxive pelvic veins that had not been diagnosed feed the varices. Duplex scanning identifies the different possible mechanisms and provides anatomical and hemodynamic data. Interventional treatment methods after varices recurrence are redosurgery, sclerotherapy and pelvic vein embolization when they are at issue. All these methods are described in details. Results provided by these treatments are analysed. Unfortunately no randomized control study enables grade A or B recommendations. Personally we suggest that ultrasound guided foam sclerotherapy should be the first-line treatment except when duplex scanning reveals an intact incompetent saphenous stump at the saphenofemoral junction or/and saphenopopliteal junction with a massive reflux filling the varicose network.

Solid photonic bandgap fiber assisted by an extra air-clad structure for low-loss operation around 1.5 microm

We demonstrate that our previous loss results [1] in an all-solid photonic bandgap fiber were in fact limited by bend loss. A new design, based on the addition of an extra ring of air holes on the outside of the all solid photonic bandgap structure, is then proposed, realized and characterized. We demonstrate that it significantly reduces both the fiber diameter and its sensitivity to bend loss.

Effects of phlebotomy therapy on cytochrome P450 2e1 activity and oxidative stress markers in dysmetabolic iron overload syndrome: a randomized trial

AIM

To assess the effects of iron removal on cytochrome P450 2E1 activity and oxidative stress in dysmetabolic iron overload syndrome.

METHODS

Forty-eight patients were randomized to phlebotomy therapy consisting of removal of 300-500 mL of blood every 14 days until serum ferritin levels dropped under 100 microg/L or to follow-up without phlebotomy therapy. Cytochrome P450 2E1 activity was measured at baseline and at the end of treatment by using the 6-hydroxychlorzoxazone/chlorzoxazone blood metabolic ratio, 2 h after the intake of 500 mg of chlorzoxazone.

RESULTS

In the treatment group, a mean of 3.9 +/- 1.3 L of blood was removed and serum ferritin levels dropped from 715 +/- 397 to 74 +/- 34 microg/L. Variation of cytochrome P450 2E1 activity was not significantly different between the 2 groups (0.07 +/- 0.26 vs. 0.03 +/- 0.19, P = 0.36). In the treatment group, low-density lipoprotein cholesterol and vitamin E were lowered after treatment compared with control group (-0.15 +/- 0.51 vs. 0.24 +/- 0.58, P = 0.002 and -1.3 +/- 4.4 vs. 2.3 +/- 5.2, P = 0.03, respectively). Inversely, vitamin C was increased (0.5 +/- 3.5 vs. -1.8 +/- 3.9, P = 0.03).

CONCLUSIONS

In dysmetabolic iron overload syndrome, reduction of iron stores does not significantly influence cytochrome P450 2E1 activity but is associated with a significant decrease of low-density lipoprotein cholesterol, suggesting that venesection therapy may be a suitable option in these patients.

Paternal age and spontaneous abortion

OBJECTIVE

To evaluate the influence of paternal age upon spontaneous abortion.

METHODS

This case-control study of 13,865 women draws on data from women's antenatal or postpartum interviews in the Jerusalem Perinatal Study, a population-based cohort derived from 92,408 births in 1964-1976. Case women (n=1,506) reported spontaneous abortion in the pregnancy preceding the interview; they were compared with women reporting live births in their previous pregnancy (n=12,359). Logistic regression was used to adjust for maternal age, maternal diabetes, maternal smoking, history of spontaneous abortions before the index pregnancy, parity at interview, and interval between the index pregnancy and the interview.

RESULTS

The adjusted odds ratio for spontaneous abortion was 0.59 (95% confidence interval 0.45-0.76, P< .0001) for pregnancies conceived from fathers aged younger than 25 years compared with those from fathers aged 25-29 years. For fathers age 40 years or older the odds ratio for spontaneous abortion was 1.6 (95% confidence interval 1.2-2.0, P=.0003) when compared with the same reference group.

CONCLUSION

Increasing paternal age is significantly associated with spontaneous abortion, independent of maternal age and multiple other factors.

Intra- and Inter-observer Reproducibility of the Recurrent Varicose Veins after Surgery (REVAS) Classification

OBJECTIVES

To evaluate intra- and inter-observer reproducibility of the classification for recurrent varicose veins after surgery (REVAS).

DESIGN

Intra- and inter-observer reproducibility of each component of the REVAS classification were evaluated by a Kappa test.

MATERIAL AND METHODS

A multi-centre study conducted in 8 countries enrolled 199 REVAS patients. Patients were examined twice by the same observer, and once by another physician. Investigations included physical examination and duplex scanning. A form based on the CEAP and the REVAS classification was filled in after each examination.

RESULTS

The analysis revealed that of the 8 items in the REVAS, intra-observer reproducibility was excellent for three items and good for five, and that inter-observer reproducibility was good for 6 items and moderate for two. Making a slight change in the proposed answers to one question, which is somewhat ambiguous, would increase inter-observer reproducibility. Analysis of the cause of intermediate reproducibility underlines the necessity of validating a duplex scanning protocol and a standardised duplex scanning report.

CONCLUSION

The good or excellent intra-observer reproducibility of the REVAS provides the main required criteria for use in clinical trials or cohort studies where patients are usually followed up by the same investigator to determine their spontaneous or treatment-related outcome.

[BNP/NT-proBNP: what is the best choice in an emergency laboratory?]

BNP and NT-proBNP are both well established as diagnostic and prognostic markers for congestive heart failure (CHF). However it remains for the biologist to choose between these two biomarkers depending on his equipment availability. The aim of this study was to compare results obtained with the Biosite Triage BNP assay and the Dade Behring NT-proBNP assay with regards to the clinical status. One hundred twelve patients (average age 76 +/- 13 years) with acute dyspnea were including and stratified by diagnosis at presentation into 3 groups: patients without acute CHF (group I, n=50), patients with non-cardiac dyspnea and CHF history (group II, n=22) and patients with acute CHF (group III, n=40). Levels of both BNP and NT-proBNP were higher among patients with cardiac dyspnea (group III) than among patients with a non-cardiac dyspnea (BNP=740 pg/mL versus 84 pg/mL; p<0.001 / NT-proBNP=7.502 pg/mL versus 499 pg/mL; p<0.001). ROC analysis for BNP or NT-proBNP were not statistically different in patients with acute CHF (group III) compared with patients with a non-cardiac dyspnea (group I + II) (AUC=0.927 versus AUC=0.930, p=0.90). Neither there was a difference between ROC analysis for BNP or NT-proBNP in patients with cardiac dyspnea (group III) compared to patients with a non cardiac dyspnea (group I) (AUC=0.981 versus AUC=0.975, p=0.76). Measurement of BNP or NT-proBNP is of identical interest for the diagnosis of acute CHF in acute dyspnea. The BNP Biosite assay was faster because analysis is performed on whole blood. With regards to analytical performance, the NT-proBNP Dade Behring assay had a higher accuracy and is highly recommended for the follow-up of CHF treatment.

[Surgery for deep venous reflux in the lower limb]

The effectiveness of the deep venous reconstructive surgery (DVRS) for reflux remains controversial. The more common etiology in deep venous reflux (DVR) is the postthrombotic syndrome, but primary deep vein insufficiency is frequently overshadowed. Valve agenesis is very rare. Clinical examination frequently does not allow distinguishing between superficial and deep venous insufficiency. In addition primary reflux is difficult to identify from secondary deep reflux.

INVESTIGATIONS

Duplex scanning provides etiologic, anatomic and hemodynamic information. Plethysmography gives information on the overall severity of the venous disease, but not on the etiology and is not reliable for identifying the predominant component when superficial and deep insufficiencies are combined. It would seem logical to go beyond these investigations only in those patients in whom surgery for DVR may be considered. In absence of contraindication (uncorrectable coagulation disorder, ineffective calf pump) complementary investigations must be carried out: ambulatory venous pressure measurement and venography including ascending and descending phlebography. The goal of DVR surgery is to correct the reflux related to deep venous insufficiency at subinguinal level. But it must be kept in mind that DVR is frequently combined with superficial and perforator reflux, consequently all these mechanisms have to be corrected in order to reduce the ambulatory venous pressure. Surgical techniques can be classified into 2 groups: those with phlebotomy and those without. Outcomes DVRS for reflux are difficult to assess as this surgery is frequently combined with superficial and perforator vein surgery, but both have been usually performed before as first step. Indication for DVRS relies on clinical, hemodynamic and imaging criteria. Etiology is also a decision factor as surgery is more often proposed in primary reflux. DVRS must be performed on specialized and high-trained centers.

Acute and reversible micrographia in a patient possibly due to cerebral ischaemia

We report a patient who developed acute and reversible micrographia, presumably due to cerebral ischaemia, on a background of mutism following a pharyngo-laryngectomy 10 years earlier. Magnetic resonance (MR) imaging showed chronic small vessel disease without evidence of an acute ischaemic lesion on diffusion-weighted sequences. Our patient's micrographia improved significantly within 12 days of symptom onset. The MR imaging was performed within 5 days of symptom onset, suggesting that the lesion was either too small for detection or had resolved on diffusion-weighted sequences.