Polymorphism of ftsI gene in Haemophilus influenzae and emergence of cefotaxime resistance in two Tunisian hospitals.

The decreased affinity to ß-lactams in Haemophilus influenzae is usually caused by specific alterations in penicillin-binding protein 3 due to varieties of substitutions in ftsI gene. This study aimed to characterize the polymorphism of ftsI gene in 19 H. influenzae strains, isolated between 2014 and 2016 (different resistance phenotypes to ß-lactams (n = 9) and susceptible strains (n = 10) used for comparative purposes). All strains were characterized for capsular type by PCR and agglutination tests and for ß-lactam resistance by amplification and sequencing of ftsI. Biotyping and clonality were performed by API-NH and pulsed-field gel electrophoresis, respectively. Four strains were ß-lactamase-negative ampicillin-resistant and five were ß-lactamase-positive clavulanic-acid-resistant. One strain from each group was resistant to cefotaxime. Our isolates belonged mainly to biotype IV and I and were non-typeable and genetically unrelated. According to mutation profiles of their ftsI, strains were classified as group I (n = 3), group II (n = 4), group-III-like (n = 1) and group III (n = 1). All group II strains were further classified as subgroup IIb, except for one strain, which harboured a new mutation (N422I). Ampicillin MICs of ß-lactamase-negative ampicillin-resistant strains were 6 to 12 times the MICs of susceptible strains. Only bla TEM-1 was detected in ß-lactamase-positive clavulanic-acid-resistant strains, and was responsible for high MICs for ampicillin (>256 mg/L), whatever the ftsI mutational resistance group. The emergence of cefotaxime-resistant isolates in our country is a matter of concern and requires strict surveillance and rationalization of antibiotic use to preserve these molecules.

[Percutaneous suture of femoral artery after diagnostic coronary angiography]. / Suture percutanée du point de ponction artériel fémoral après coronarographie diagnostique.

UNLABELLED: Complete local haemostasis after femoral artery catheterization can be performed using percutaneous suture devices. To evaluate efficacy and safety of these systems after diagnostic coronary angiography, we performed a randomized study where patients were treated either with a manual compression (group C) or a percutaneous suture (group T). Fifty patients were included in each group. Patients in group C had to rest at bed during 24 hours while patients in group T had to stand up and walk immediately after complete haemostasis was obtained. All angiographies were performed using a 6 F sheath. All patients had a clinical evaluation and an echography 24 hours after the procedure and all were reached by phone call at 15 days. Both groups were similar in term of age, sex ratio, diabetes, height and weight. Complete haemostasis was obtained in 20 +/- 6 mn in group C and in 6 +/- 10 mn in group T (p < 0.001). Device technical success rate in group T was 90%; 70% of patients walked immediately down the X ray table and 90% before the 4 hours. Ambulation delay was 24 +/- 5 hours in group C and 5 +/- 9 hours in group T (p < 0.0001). Clinical and echographic complications rate were similar in both groups (8%). There was no post procedure complication in group T (especially after ambulation) nor at the phone call. CONCLUSION: Femoral artery percutaneous suture after diagnostic coronary angiography is as safe and working than manual compression. It allows an immediate mobilization and ambulation, far earlier than compression.

[Ultrasonic imaging of coronary atherosclerosis]. / Imagerie ultrasonore de l'athérosclérose coronaire.

Intra-coronary ultrasonography (ICV) is a technique for in vivo study of the different layers of the arterial wall, the site of atherosclerosis. A qualitative analysis of the composition of the plaque can predict its potential evolutivity (chronic with slow progression or at risk of rupture and causing acute thrombosis) and its response to different types of angioplasty, which could eventually become and essential factor in the choice of appropriate therapeutic strategy. Analysis of the results of B mode ultrasonic scanning has provided correlations with the histological composition of the arterial wall, validating the method and opening up the field of tissue characterisation which hitherto had been limited by the absence of sufficiently reliable, accurate and reproducible quantitative parameters. Magnetic resonance imaging (MRI) is a complementary, non-invasive tool for tissue analysis because its sensitivity to the biophysical and biochemical properties of tissues which makes it a promising method of morphological and functional imaging. Other methods of imaging atheromatous plaques include angioscopy and optic coherence tomography which have also contributed to the improvement in our knowledge of atherosclerosis. These methods of imaging which are slowly overcoming their limitations provide documents which ressemble more and more the histological appearances. Intracoronary ultrasonography is the most promising method and raises hopes that one day we shall be able to predict the outcome and anticipate the risk of rupture of atherosclerotic plaques.

[Intra-coronary ultrasonography during angioplastic procedures]. / Apports de l'échographie endocoronaire en cardiologie interventionnelle.

Thanks to miniaturization and constant improvement of technologies, intracoronary ultrasound (ICUS) progressively takes its place as the best tool to accurately analyze arterial wall structure. However, its routine use during interventional procedures remains limited. ICUS provides precious informations, complementary to angiography, and guide interventional procedures on the basis of a more accurate analyze of the components of the plaque, thus improving their success rate. Since its use favorized the understanding of the different devices mechanisms (angioplasty, stents, directional and rotational atherectomy), ICUS contributed to reduce the incidence of their complications. Many studies have emphasized ICUS interest during these procedures: their results seem to be significantly improved by the way of prompting the operator to adopt an aggressive strategy (additional inflations using high pressures, combination of different techniques...) which tend to reduce the complication rate and the restenosis incidence. Actually, the restenosis rate was in all these studies [OARS (29%), ABACAS (21%) and MUSIC (8.3%)] directly associated to ICUS parameters measured immediately after treatment, particularly the residual plaque burden. Whether its use, that engender substantial cost, cannot be systematic, trained centers will probably demonstrate that a rational and suitable use lead to adopt optimal strategies and achieve improved results.

[Physiology of coronary circulation and angioplasty: utopia or clinical reality?]. / La physiologie de la circulation coronaire et l'angioplastie: utopie ou réalité clinique?

Small pressure transducer and Doppler quartz placed at the tip of angioplasty guide wire give the opportunity to measure coronary flow physiology parameters, the physiopathologic impact of an epicardic coronary stenosis and the efficacy of its treatment. This gives the opportunity to over ride the coronary imaging limitations. Doppler and pressure investigate a different and complementary aspect of the pressure-flow relation and may be used together in some special cases. Myocardial fractional flow reserve (FFRmyo) and relative coronary reserve concepts allow to evaluate patients with heterogeneous coronary reserve. Clinical application field is very broad and can be applied to each step of coronary angioplasty from the evaluation of intermediate lesions and the indication of angioplasty to the guidance of the procedure to the evaluation of the result, through the stenting indication and the stent placement optimization. Numerous studies has emphasized the role of physiologic coronary assessment in the cathlab. The time and economic gain of such an attitude has to be confirmed by future trials but it is clear now that it is not possible to continue to take decision on the sol visual aspect of a lesion.

[Diagnostic value of endocoronary echography]. / Apport diagnostique de l'échographie endocoronaire.

Intracoronary ultrasound allows in vivo examination of the various layers of the wall of arteries affected by atherosclerosis. Its use in the catheterisation laboratory has therefore allowed better understanding of the mechanism of the action of the various angioplasty procedures, allowing better guidance of the indications and better control of these techniques. It also helps to guide these procedures, thereby facilitating an optimal immediate result, which determines the long-term outcome. The characteristics of intracoronary ultrasound (high resolution, proximity of the arterial wall, echogenicity of constituents of the plaque) make it the instrument of choice to study the composition and structure of the plaque, which determine the clinical presentation and active potential, especially the risk of complications (rupture). The development of image and crude acoustic signal processing techniques have improved the performance of the analysis of these documents and raise hopes of one day being able to predict and anticipate plaque rupture.

[Platypnea-orthodeoxia revealed by recurrent syncope episodes]. / Platypnée-orthodéoxie révélée par des syncopes à répétition.

Platypnea-orthodeoxia is a rare clinical condition which must be examined as a differential diagnosis for any bout of faintness occurring during standing or dyspnea that is exacerbated by standing. This syndrome is often associated with a patent foramen ovale. Its physiopathology is not univocal and the association of many anatomical criteria seems to be mandatory. Contrast echocardiography confirms diagnosis and closure of the patent foramen ovale during interventional catheterization and is currently the therapeutic method of choice. After closure of the foramen ovale, clinical improvement is spectacular and durable.

Nosocomial outbreak of imipenem-resistant Pseudomonas aeruginosa producing VIM-2 metallo-ß-lactamase in a kidney transplantation unit.

BACKGROUND: Twenty four non replicate imipenem resistant P. aeruginosa were isolated between January and November 2008, in the kidney transplantation unit of Charles Nicolle Hospital of Tunis (Tunisia). This study was conducted in order to establish epidemiological relationship among them and to identify the enzymatic mechanism involved in imipenem resistance. METHODS: Analysis included antimicrobial susceptibility profile, phenotypic (imipenem-EDTA synergy test) and genotypic detection of metallo-ß-lactamase (MBL) (PCR), O-serotyping and pulsed-field gel electrophoresis. RESULTS: All strains showed a high level of resistance to all antimicrobials tested except to colistin. The presence of MBL showed concordance between phenotypic and genotypic methods. Sixteen isolates were identified as VIM-2 MBL-producers and 13 of them were serotype O4 and belonged to a single pulsotype (A). CONCLUSIONS: This study describes an outbreak of VIM-2-producing P. aeruginosa in a kidney transplantation unit. Clinical spread of blaVIM-2 gene is a matter of great concern for carbapenem resistance in Tunisia.

Implications of the International Health Regulations (2005) for communicable disease surveillance systems: Tunisia's experience.

BACKGROUND: In May 2005, the revised International Health Regulations, known as IHR (2005), were adopted in response to the evolving nature of communicable diseases (CD) and the rapid increase in global trade and travel. CD surveillance is an integral part of a country's core requirements under the regulations. METHODS: The implications of these requirements were assessed as part of a review of the national CD surveillance system of Tunisia using a qualitative methodology of strengths, weaknesses, opportunities and threats (SWOT). RESULTS: Tunisia is some way towards meeting the requirements of IHR (2005) while some specific areas that need to be addressed are highlighted for improvement: standardization of surveillance documents, strengthening the role of the laboratory in surveillance, increased human resources and training. CONCLUSIONS: Tunisia's experience can offer some lessons to other countries in this process. While meeting the capacity obligations of IHR (2005) requires investment and commitment, this investment will enable countries to better protect themselves against public health emergencies arising within their borders and threatening from elsewhere in the world.

NMR spectroscopy, X-ray crystallographic, and molecular modeling studies on a new pyranone from Haloxylon salicornicum.

A new pyranone, 5-hydroxy-3-methoxy-4H-pyran-4-one (1), was isolated from the aerial parts of the desert shrub Haloxylon salicornicum. The structure was elucidated by X-ray structural analysis, NMR spectroscopy, and mass spectrometry. The monoacetate was also prepared, and molecular modeling studies and full NMR data were recorded.