Portage d’entérocoques résistants aux glycopeptides : les techniques d’isolement et d’identification actuelles sont-elles suffisantes ?

The monitoring of infection by glycopeptide-resistant enterococci (GRE) is one of the main elements of hospital hygiene policy. It involves systematic rectal swabs in clinics at risk (asymptomatic carriage).

Aim

We compare two GRE screening methods and evaluate a new kit associating multiplex PCR and hybridization (Génotype^® Enterococcus, Hain Lifescience) on a panel of 448 samples collected over a 4-month period.

Patients and methods

The first method is based on direct inoculation of the sample; the second one involves a preliminary enrichment phase followed by molecular diagnosis allowing the identification of species of enterococci as well as glycopeptide resistance genes.

Results

All the resistant strains were isolated using the enrichment technique. The incidence of GRE (VanA) carriage was 0,55% (two out of 362 patients, two out of 448 isolates) with two Enterococcus faecium VanA. Six Enterococcus gallinarum VanC1 and two Enterococcus casseliflavus VanC2/C3 were also isolated and identified. The main clinics concerned are intensive care and hematology. The two patients with E. faecium VanA had been previously given glycopeptides for 10 days. For three strains, the molecular method allowed to correct prior erroneous results based on rapid identification (RapidID32Strep V2.0).

Conclusion

The method using direct samples inoculation underestimates real incidence of GRE carriage. The performances of Génotype^® Enterococcus molecular method, evaluated for other parameters using reference strains and DNA sequencing, offer new possibilities applicable to routine laboratory.     

Le dépistage en ambulatoire des patients porteurs de Staphylococcus aureus ou présentant une colonisation urinaire et devant bénéficier d’une chirurgie orthopédique est-il réaliste ?

Aim of the study

Evaluate the feasibility of Staphylococcus aureus nasal colonization and bacteriuria screening in outpatients before realizing a decolonization treatment in S. aureus carriers and a bacteriuria treatment before hospitalization.

Méthods

All patients undergoing hip, knee or back surgery in which prosthesis were implanted between October 2007 until the end of June 2008 were included. Microbiological studies were performed before hospitalization. Notice for S. aureus decolonization regimen was delivered to each patient and to the general practitioner only if the patient had nasal carriage.

Results

Only 91.2 % (240/263) of patients had microbiological results. Prevalence of S. aureus colonization was 21.4 % (48 positives/224). Three patients were colonized with methicillin-resistant staphylococci. Decolonization regimen was applied before surgery to 70.8 % (n = 34) of the colonized patients. Among the patients, 8.9 % (20/225) had bacteriuria, Escherichia coli being the most frequent micro-organism (n = 16).

Conclusion

Preoperative search and management of S. aureus colonization and of bacteriuria in outpatients is possible. Monitoring record must be performed by a member of the hospital staff.     

Allogreffe de cellules souches hématopoïétiques à partir d’un sang cordon non apparenté : quelle unité choisir ?

In the attempt to harmonize clinical practices between different French transplantation centers, the French Society of Bone Marrow Transplantation and Cell Therapy (SFGM-TC) set up the third annual series of workshops which brought together practitioners from all member centers and took place in October 2012 in Lille. Here we report our results and recommendations regarding the choice of optimal unrelated cord blood unit in terms of cell dose, HLA-matching and other characteristics.     

Prévalence des souches de Escherichia coli et de Klebsiella pneumoniae productrices de β-lactamases à spectre étendu de type CTX-M à l’hôpital Bretonneau (CHRU de Tours)

The CTX-M type extended spectrum β-lactamases constitute a rapidly growing cluster of enzymes that have disseminated geographically. This study evaluates the prevalence of these enzymes in the university hospital in Tours, in 2007. Twenty-eight strains were studied: 21 Escherichia coli and seven Klebsiella pneumoniae. The gene bla_CTX-M was detected by real-time PCR for 27 strains. The CTX-M-1 group, including CTX-M-15, was the most frequent CTX-M-type enzyme.     

Contractualisation interne : expérience du service de transfusion et d’immunologie de Rabat

The management by objectives method has become highly used in health management. In this context, the blood transfusion and haemovigilance service has been chosen for a pilot study by the Head Department of the Ibn Sina Hospital in Rabat. This study was conducted from 2009 to 2011, in four steps. The first one consisted in preparing human resources (information and training), identifying the strengths and weaknesses of the service and the identification and classification of the service's users. The second step was the elaboration of the terms of the contract, which helped to determine two main strategic objectives: to strengthen the activities of the service and move towards the “status of reference.” Each strategic objective had been declined in operational objectives, then in actions and the means required for the implementation of each action. The third step was the implementation of each action (service, head department) so as to comply with the terms of the contract as well as to meet the deadlines. Based on assessment committees, the last step consisted in the evaluation process. This evaluation was performed using monitoring indicators and showed that management by objectives enabled the Service to reach the “clinical governance level”, to optimize its human and financial resources and to reach the level of “national laboratory of reference in histocompatibility”. The scope of this paper is to describe the four steps of this pilot study and to explain the usefulness of the management by objectives method in health management.     

Virus de l'hépatite G et produits sanguins labiles : rôle de la transmission transfusionnelle

The GBV-C/HGV (HGV) virus was discovered a few years ago. This virus is known to be parenterally as well as sexually transmitted. However, no study has found some pathogenic roles for HGV so far. In the present study, we aimed to investigate the transmission of HGV by blood components transfused to 284 patients hospitalized in surgery unit in 1995. We tested two parameters of infection in blood components transfused to infected recipients: viral RNA by PCR and anti-E2 antibodies by ELISA. We tried to suspect some potent hepatocyte impacts by assessing the levels of two enzymes in serums: alanine aminotransferase (ALT) and alpha-glutathion S-transferase (α-GST). We found that HGV-RNA was detectable in 3.6% of recipients prior to transfusion and 7.5% post-transfusion. For each infected recipient, we retrospectively did a search for HGV-RNA in each transfused blood component, and we found at least one blood component as HGV-RNA-positive for each transfusional infected recipient. Anti-E2 antibody prevalence standing for a former and cured infection was 39.6% in all the recipients. In viremic recipients, ALT levels were mostly normal, while α-GST levels were found more commonly elevated than in non-viremic recipients although non-significantly (20% vs. 6.3%; P = 0.07). The present study underlines that HGV transmission is mostly transfusional in surgery units, and that infectiosity of blood components can be anticipated by detection of the viral RNA by PCR. Furthermore, the possible relationship between the serum activity of α-GST and the hepatotropism of HGV, although non-admitted as pathogenic, should be investigated.     

Risque résiduel de transmission du VIH et du VHB par transfusion sanguine entre 2003 et 2005 au Centre national de transfusion sanguine de Dakar (Sénégal)

Background and aimUsing of safety blood products did not stop improving these last years. The use of effective methods as well immunologicals as virologicals ones really reduces risk associated to blood transfusion. However, it persists residual risk (RR) of transfusion transmitted viral diseases. The aim of our study was to detect cases of seroconversion for HIV,and HBV among donors in the Senegalese national blood bank. And then, we estimated the RR of these virus.MethodsWe led a transverse retrospective study from 2003 (January 1st) to 2005 (December 31st). Had been included donors with at least two donations of blood during the period of study. They had to be seronegative for HIV and HBV after the first donation. All donors with only one donation had been excluded. RR was estimated by multiplying incidence rates by the durations of the window periods.ResultsDuring 3 years, we collected 425,503 donations; 388 were positive for HIV and 4240 for HBV. But we noted only two cases of seroconversion for HIV and 23 for HBV. So, RR estimated was 3,5 in 100,000 donation for HIV and 102,45 in 100,000 donations for VHB.ConclusionIt emerges from this study that the risk of blood transmitted virus is always high. Introduction of more sensitive tests (as nucleic acid testing) would allow us to deliver more safety products.     

Virus et hôte. Interactions du virus et de l'organisme

Sans résumé     

Profil clinico-biologique et immunohématologique des patients atteints de β-thalassémie en Tunisie : à propos de 26 cas

Aim of the studyTo study the clinical and biological profile of β-thalassemic patients in our region, reflecting the quality of their care.Patients and methodsA retrospective study (2010–2011) on 26 β-thalassemic patients followed in the pediatrics service at CHU Farhat Hached Sousse, Tunisia. Epidemiological, clinical and biological data were collected from medical records and transfusion files of patients. The transfusion protocol adopted was to maintain a hemoglobin level > 10 g/dL by regular transfusions every 3–4 weeks. Iron chelation therapy, in order to maintain serum ferritin < 1500 ng/mL, was introduced when serum ferritin exceeded 800–1000 ng/mL.ResultsThe mean age of patients at diagnosis was 15 months. The clinical impact of anemia had resulted in failure to thrive in 54% of patients and facial dysmorphism in 23%. The average transfusion requirement was estimated at 311.02 mL/kg/year with 6 cases of hyperconsumption. The immunohaematological monitoring showed the appearance of anti-RBC alloimmunization in one patient and 4 cases of autoimmunization. Poor adherence of chelation therapy was 62% and causing 5 cases of cardiac complications, 4 cases of liver injury and 14 cases of endocrine complications.ConclusionImproving the therapeutic care of β-thalassemic children requires better monitoring of transfusion recovery and improved adherence to chelation therapy.     

Le troisième et nouveau visage de la maladie de Chagas

After the publication of the results of the BENEFIT study concluding that the benznidazole (5 mg/kg/d/60 d) is ineffective to stop the progression of the established Chagas’ cardiomyopathy in adults, the author evokes the new experiences and the new challenges of 2016 regarding Chagas disease while speculating on its future and by calling back some elements little known of his history, in particular the fact that it is Chagas who invented about it to some extent the concept of “neglected disease”.     

Évolution de la sensibilité de Staphylococcus aureus aux antibiotiques : la méticilline est-elle encore un marqueur de multirésistance ?

Objective

Recent change was noted in S. aureus epidemiology, especially for none multiresistant methicillinresistant S. aureus (MRSA) and for multiresistant methicillin-susceptible S. aureus (MSSA). So, a six-year retrospective study was conducted to follow trends in antimicrobials resistance and to determine if methicillin remained a relevant multiresistant marker.

Methods

All S. aureus isolates (duplicates excluded) isolated between 2001 and 2006 in a French 800-beds-teaching-hospital were included in the study.

Results

Four thousand four hundred and fifty-five isolates providing from 3602 patients were identified between 2001 and 2006. MRSA rate and incidence for 1000 hospitalization-days significantly decreased from 34.7 to 22.6% and 1.3 to 0.6% respectively (p < 0.001). Significant decrease was observed for multiresistant MRSA (72.9 to 46.3%, p < 0.001), while no change was observed for multiresistant MSSA (2.9 to 3.4%). Among the 186 different antibiotic patterns isolated, four MRSA-phenotypes significantly decreased whereas two MSSA-phenotypes significantly increased. The main MRSA phenotype, resistant to kanamycin, tobramycin, macrolides-lincosamides-streptograminesB, and fluoroquinolones, significantly decreased from 11.9 to 5.9% (p < 0.001). Glycopeptide Intermediate S. aureus (GISA) phenotypes disappeared.

Conclusion

At this date, methicillin remains in our institution a relevant marker of multiresistance but trend is changing.     

L'inactivation dans l'eau de mer et l'eau d'alimentation de certains entérovirus

Sans résumé