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Molecular typing of extended spectrum beta lactamase producing nbsp klebsiella pneumoniae nbsp strains isolated in the university hospital center of Dakar

In head and neck cancer surgery antibiotic prophylaxis is effective in reducing the incidence of surgical site infections (SSI). However, controversies between antibiotic prophylaxis and curative antibiotic therapy exist, particularly when complex and decaying surgeries are performed in risky underlying conditions, with a risk of persisting salivary effusion in the postoperative period, or in the case of reconstruction with myo-cutaneous flaps. We have performed a systematic review of the literature according to PRISMA recommendations to answer the following questions: indications for antibiotic prophylaxis and curative antibiotic therapy, optimal duration, and choice of antibiotics for prophylaxis in head and neck cancer surgery. Literature analysis allows to conclude that patients undergoing Altemeier classes 2 and 3 surgical procedures should receive perioperative antibiotic prophylaxis restricted to the first 24 postoperative hours. No benefit has been shown with its extension beyond these 24 hours. The most adapted combinations of antibiotics in this setting are "amoxicillin+clavulanic acid" and "clindamycin+gentamicin". However, the level of evidence regarding the most decaying surgeries with high risk of SSI is low, making it necessary to perform new high-powered randomized trials in these patients. Eventually, it should be noted that antibiotic prophylaxis should be an integral part of SSI preventive measures, including application of hygiene measures, and postoperative monitoring of SSI clinical signs.

Resume Parmi les bacilles a Gram negatif, le role des β-lactamases dans les resistances naturelles ou acquises est essentiel et de plus en plus complexe. De nombreux genes gouvernant ces resistances sont chromosomiques, ou portes par des plasmides, des integrons ou encore lies au CR (Common Region) : ils ont ete clones et sequences, montrant une considerable diversite parmi les enzymes inactivant les s-lactamines. Une serie de reponses genetiques sont developpees par les bacteries apres introductions successives de nouveaux antibiotiques tels que les β-lactamines. Cette adaptabilite du monde bacterien doit conduire a limiter l’abus de prescriptions et un meilleur usage des antibiotiques.

We aimed to detect the extended-spectrum β-lactamases (ESBLs) secreted by clinical strains of Escherichia coli at Fann University Hospital in Dakar and to characterize them molecularly. We identified 32 isolates producing ESBLs. The CTX-M-15 gene was the most frequently detected ESBL gene, detected in 90.63% of the isolates studied.

Les methodes d'epidemilogie moleculaire ont beaucoup evolue ces dernieres annees. Elles fournissent une empreinte genetique des bacteries soit de leur chromosome, soit de leur contenu en ADN plasmidique. Leur mise en œuvre necessite une bonne maitrise des techniques de biologie moleculaire. Elles font parfois appel a des methodes recentes comme l'electroporese en champ pulse ou la PCR, egalement parfois a des techniques tres minutieuses comme les techniques d'hybridation, et utilisent dans certains cas des produits dangereux comme des isotopes radioactifs, des solvants comme le phenol et des agents intercalants comme le bromure d'ethidium. C'est, entre autre, une des raisons pour lesquelles l'utilisation de ces methodes doit etre faite a bon escient. L'utilisation d'etalon interlaboratoire a chaque manipulation et de logiciels informatiques permettra bientot une lecture et une interpretation objective et fiable des profils obtenus.

Resume Compte tenu de l'eventualite actuelle plus grande d'isoler chez l'homme des souches de Bordetella bronchiseptica, la sensibilite de 23 souches a ete determinee, par la methode de diffusion, vis-a-vis de 35 antibiotiques et comparee a celle d'Alcaligenes (A. faecalis, A. denitrificans subsp. xylosoxydans) qui presentent des caracteres proches de ceux de B. bronchiseptica. Toutes les souches testees sont sensibles a: amoxicilline, ticarcilline, mezlocilline, piperacilline, cefoperazone, latamoxef, imipeneme, kanamycine, neomycine, gentamicine, tobramycine, netilmicine, amikacine, acide nalidixique, pefloxacine, colistine, tetracycline, minocycline et erythromycine. Mais elles sont intermediaires ou resistantes a : mecillinam, cefalotine, cefamandole, cefoxitine, cefuroxime, cefotaxime, aztreonam, streptomycine, spectinomycine, acide pipemidique, rifampicine, fosfomycine et trimethoprime. Enfin une faible synergie est observee entre l'amoxicilline et l'acide clavulanique. L'etude comparative de la sensibilite, en particulier aux β-lactamines et aux aminosides a permis de differencier les souches de B. bronchiseptica de celles d'A. faecalis ou d'A. denitrificans subsp. xylosoxydans. Ce phenotype de resistance propre a B. bronchiseptica constitue donc, une aide au diagnostic d'autant plus utile que ces trois especes presentent des caracteres d'identification tres voisins.

Intragenic DNA probes were synthesized by polymerase chain reaction using fragments of the genes of three major types of β-lactamases (TEM, SHV, CARB) as templates. The TEM probe hybridized with the genes encoding TEM-1, TEM-2 and six extended-spectrum related enzymes (TEM-3 to TEM-7, TEM-20) in colony hybridizations and Southern-blot analysis. The SHV probe hybridized with the genes for SHV-1, OHIO-1 and four derived extended-spectrum β-lactamases (SHV-2, SHV-3, SHV-4 and SHV-5). The CARB probe hybridized with the genes for PSE-1 (CARB-2), PSE-4 (CARB-1), CARB-3 and CARB-4. None of the probes hybridized with genes for any of eight oxacillin-hydrolysing enzymes, PSE-2, OXA-1 to OXA-7, ROB-1 and chromosomal β-lactamases of various Enterobacteriaceae (except Klebsiella pneumoniae) and Pseudomonas aeruginosa. Investigations of Escherichia coli clinical isolates using these probes indicate the presence of a novel type of extended-spectrum, transferable β-lactamase.

We report a case of actinomycosis caused by actinomyces israelii, related to the removal of intrauterine device (IUD). Diagnosing actinomycosis is difficult but should be considered in the event of any acute abdominal problems in a woman carrying an IUD. All abdominal organs may be affected. Even with a disseminated infection, the combination of appropriate antibiotic therapy (penicillin G) and surgery ensures a full recovery in most cases.

The genetic organization of the gene coding for DHA-1 and the corresponding ampR gene was determined by PCR mapping. These genes have been mobilized from the Morganella morganii chromosome and inserted into a complex sulI-type integron, similar to In6 and In7. However, they are not themselves mobile cassettes. This integron probably includes a specific site for recombination allowing the mobilization of diverse resistance genes, as observed for bla(CMY-1) and bla(MOX-1).

Background The optimization of antibiotic therapy has become a major issue. Indeed, the evolution of bacterial resistance requires prescribers to reserve use of antibiotics and especially carbapenems. Various bodies have made recommendations to improve antibiotic regimens and thus preserve the effectiveness of these major antibiotics. At Tenon Hospital, a multidisciplinary unit was created in May 2011. It includes clinicians, bacteriologists, hygienists and pharmacists. Meropenem and ertapenem were already controlled whereas imipenem and doripenem were given without restrictions before May 2011. Purpose To assess the impact of this new organisation, a study compared the requirements for carbapenems before and after the antibiotic management team was created. Materials and Methods All patients who received at least one dose of carbapenem were included. Bacteriological and biological characteristics of each patient were found. The compliance of each prescription with the available guidelines was assessed studying the duration of treatment, dose and indications. Two periods were defined: the first between January 2009 and September 2010 and the second between June 2011 and May 2012. Results Duration of the treatment was the single criteria that had changed for ertapenem and meropenem. The impact of this team is greater for the prescriptions of doripenem and imipenem. Establishment of that team shortened the duration of treatment: 2 days for doripenem and 4 days for imipenem. The number of unjustified prescriptions of imipenem decreased from 45% to 5% for empirical treatments and from 51% to 20% for documented treatments. Conclusions Reduced length of treatment is important and reduces the selection pressure. This explains why carbapenem-resistant bacteria have been isolated only four times in the past year. Results obtained are similar to those obtained in two Parisian hospitals. No conflict of interest.

Three cases of cutaneous bacillary angiomatosis in HIV-infected patients are reported. They differed profoundly with respect to the extent of the lesions and the clinical course. In two cases, Rochalimaea quintana was identified by direct sequencing of the DNA amplified with the polymerase chain reaction (PCR), whereas an easy, rapid method based on the restriction length of polymorphism analysis of PCR products (PCR-RFLP) was used in the third case. This report illustrates the variations in clinical presentations and evolutive profiles in patients with bacillary angiomatosis, and confirms the causal role of R. quintana in this disease.

The accuracy of paired quantitative blood cultures (PQtBCs) collected in pediatric Isolator 1.5-ml tubes compared to central venous catheter (CVC) segment cultures (hub and tip) to diagnose catheter-related bacteremia (CRB) was evaluated in 58 bacteremic adult patients. The second aim of this study was to state precisely whether the tip or the hub (or both) of the infected device was the source of the bacteremia in case of significant results of PQtBC. Fifty-eight bacteremic patients with suspected CRB entered the study. In 52 patients, the diagnosis was obtained before CVC removal by PQtBC and was confirmed by CVC segment cultures: CRB in 30 patients, non-catheter-related bacteremia in 22 patients. Six patients had CRB not found by PQtBC. 1) PQtBC is 83% sensitive, 100% specific (negative predictive values 78%, positive predictive values 100%). 2) Sixteen bacteremic patients had authentic hub-related bacteremia (positive hub culture associated with negative tip cultures). When CRB is suspected in bacteremic patients, a negative tip culture cannot exclude the diagnosis of CRB. In all cases, CVC tip culture must be associated either with PQtBC or with hub cultures.

Intragenic DNA probes were synthesized by polymerase chain reaction using fragments of the genes of three major types of beta-lactamases (TEM, SHV, CARB) as templates. The TEM probe hybridized with the genes encoding TEM-1, TEM-2 and six extended-spectrum related enzymes (TEM-3 to TEM-7, TEM-2O) in colony hybridizations and Southern-blot analysis. The SHV probe hybridized with the genes for SHV-1, OHIO-1 and four derived extended-spectrum beta-lactamases (SHV-2, SHV-3, SHV-4 and SHV-5). The CARB probe hybridized with the genes for PSE-1 (CARB-2), PSE-4 (CARB-1), CARB-3 and CARB-4. None of the probes hybridized with genes for any of eight oxacillin-hydrolysing enzymes, PSE-2, OXA-1 to OXA-7, ROB-1 and chromosomal beta-lactamases of various Enterobacteriaceae (except Klebsiella pneumoniae) and Pseudomonas aeruginosa. Investigations of Escherichia coli clinical isolates using these probes indicate the presence of a novel type of extended-spectrum, transferable beta-lactamase.

A clinical isolate of Klebsiella pneumoniae sensu lato isolated from throat and a blood culture taken from a neutropenic patient treated for 2 weeks with ceftazidime and vancomycin was resistant to ceftazidime (MIC: 32 micrograms/ml) and moderately susceptible to aztreonam (MIC: 4 micrograms/ml). The isolate contained a plasmid of 180 kb which, when transferred to Escherichia coli by conjugation, conferred resistance to ceftazidime and tetracycline. The transconjugant had decreased susceptibility to ceftazidime (128-fold) and aztreonam (8-fold). Clavulanic acid and sulbactam each inhibited the resistance and clavulanic acid showed a synergistic effect when associated with ceftazidime and aztreonam. An extended-spectrum beta-lactamase with an isoelectric point of 7.6 was detected in the clinical isolates from blood and its transconjugant. This beta-lactamase showed similar substrate and inhibition profiles to SHV-1. In particular it did not hydrolyse ceftazidime. Hybridization with an intragenic probe for SHV-3 indicates that this beta-lactamase is an SHV-type enzyme. We propose that this novel CAZ-type extended-spectrum beta-lactamase be named SHV-6.

Cat-scratch disease (CSD) is a benign inoculative lymphoreticulosis, first described in independent reports by Pierre Mollaret [1] and Robert Debre in 1950 [2]. The disease usually self-limited, with spontaneous resolution occurring after several weeks, appears to be related to the presence of an identified gram-negative bacteria.

Paired quantitative blood cultures collected simultaneously via catheter and peripheral vein in Isolator 1.5 ml tubes, were performed in 50 febrile hematology children. Samples were taken to diagnose catheter-related sepsis (CRS) without catheter removal and to monitor the therapeutic efficiency of antimicrobials administered through the infected device by infusion and/or by the antibiotic lock technique (ALT). In 7 children (14%) the colony counts from catheter blood samples were 30-fold higher than the colony counts from peripheral samples, suggesting CRS; in 7 other patients (14%), identical colony counts in both samples suggested sepsis was not catheter-related. One patient (2%) had septicemia caused by E. coli found in the urinary tract; only the peripheral blood cultures were positive. In 6 patients (12%), the Isolator system was not effective for diagnosing bacteremia or CRS; in 29 patients (58%) the febrile episode was not microbiologically documented. All episodes of CRS were cured whatever the treatment was: infusion or ALT.

We have shown that the combination of teicoplanin (T) and ceftriaxone (C) given once daily as first-line empirical antimicrobial therapy is very effective (85%) and safe in febrile neutropenic children (ICAAC, 1988). Like others (ICAAC, 1989) we have stressed the new life-threatening problems with Streptococcus mitis and Strep. sanguis. Considering the regular sensitivity of Gram-positive organisms to T, it is possible that the introduction of the glycopeptide at the onset of aplasia may be helpful. The high incidence of fungal infection or superinfection supports the routine use of an effective antifungal agent when fever is still present or relapse occurs. Our study was designed to assess the prevention of (1) staphylococcal and streptococcal infections using T when the central catheter is being placed, and (2) candida infection by the simultaneous use of a new anti-mycotic agent fluconazole (F) administered once-daily. Patients were randomized into two arms of the study. Arm A received T 6 mg/kg/d and F 3 mg/kg/d starting when the catheter was put in place. If fever occurred, C 50 mg/kg/d and amikacin (A) 15 mg/kg/d were added and T increased to 10 mg/kg/d. If a febrile relapse occurred, amphotericin B was added. In arm B the combination of the three agents T 10 mg/kg/d, C 50 mg/kg/d and A 15 mg/kg/d was started only if there was fever. Amphotericin B was used in febrile relapses. Forty-six patients were eligible (23 in each arm; no statistically significant differences between the two groups). The mean age of the patients was 8 years and mean duration of aplasia 23 and 24 d. Results were as follows: arm A the duration of T + F alone was 10 d, 22 patients had a febrile episode with 1 Gram-positive, 11 Gram-negative and one candida strain isolated in eight patients. C + A were effective in 72% of these patients. There were no deaths. In arm B, fever occurred in all patients during the first 6 d, with eight Gram-positive and six Gram-negative organisms isolated in nine patients. C + T + A were successful in 83% of patients. A bacterial superinfection was documented in four patients, candida superinfection in seven patients and one patient died from Candida parakrusei septicaemia. When the total amount of C and A used in both arms was compared, there was a reduction in 20% of the two agents in arm A, but T was equivalent in both arms. Treatment was well tolerated in both arms.(ABSTRACT TRUNCATED AT 400 WORDS)

Cat-scratch disease is a benign inoculative lymphoreticulosis, related to the presence of a polymorph bacillus, Warthin-Stary silver stained, Gram negative as assessed by Brown-Hopp staining. It is found in the capillary walls and in macrophages bordering the lymph node sinusoids at the site of inoculation, in regional subacute adenopathy before softening, in internal organs and blood cultures of systemic infections, occurring more often in immuno-compromised patients. These bacteria have been demonstrated in subcutaneous vascular nodules, near to histiocytoid hemangioma in AIDS patients; these lesions are very similar to early stage Kaposi's sarcomas. This bacteria is provisionally listed as G 1492 by the Center for Disease Control.

We evaluated air contamination with bacteria and fungi in a transplantation unit, successively housed in two buildings. Bacterial air contamination was least in laminar air flow rooms, and reduced in ultraclean air rooms in comparison with conventional rooms. Similar results were obtained with culture of air for fungi.

Resume Nous avons realise durant 6 mois une etude prospective dont le but etait de tester l'interet du systeme d'hemocultures quantitatives Isolator 1,5 ml chez des enfants febriles porteurs d'un catheter veineux central (CVC) hospitalises en hematologie pediatrique. 54 enfants d'âge moyen 7 ans, traites pour leucemie aigue (45), lymphome (5), tumeur solide (3), aplasie idiopathique (1), ont ete inclus. En cas de syndrome febrile, etaient prelevees de facon simultanee au CVC et sur une veine peripherique (VP), des hemocultures sur tube Isolator et sur flacon Bactec. Sur 50 observations exploitables, 15 enfants ont eu des hemocultures positives sur tube Isolator. Chez 7 d'entre eux le nombre d'unites formant colonies (UFC)/ml etait tres superieur (x 2.10 a 1.10 6 ) dans l'echantillon sanguin preleve au CVC par rapport a l'echantillon preleve en peripherie, il s'agissait donc d'une septicemie a point de depart du CVC. Tous ont gueri CVC en place. Chez les 8 autres le nombre d'UFC/ml etait identique dans les prelevements au CVC et en VP permettant d'exclure la responsabilite du CVC dans l'infection. La sensibilite d'Isolator 1,5 ml dans notre etude est de 71,5 % et sa specificite de 100 %. Cette methode permet donc de diagnostiquer les septicemies a point de depart du CVC et de surveiller l'efficacite therapeutique de l'antibiotherapie CVC en place.

Four patients developed legionnaires' disease after bone marrow transplantation. Two cases occurred early after transplant and were considered as part of a hospital epidemic due to contamination of water supply. The other two cases were considered to be sporadic because they occurred 3-4 weeks after hospital discharge. The outcome was good in two patients. In the third patient, recurrent disease was probably due to acquired resistance to macrolides, and complete cure was achieved after treatment with pefloxacin and rifampicin. The fourth patient died of overwhelming infection despite early treatment with erythromycin and pefloxacin. During the same period we treated 14 patients with pefloxacin for prevention of bacterial infection, of whom none developed Legionella pneumophila infection, while three of the patients reported here were in a group of 11 patients who received only oral non-absorbable antibiotics for gut decontamination. The fourth patient in this report was receiving no antibiotics. Thus pefloxacin seems to be effective as prophylaxis against L. pneumophila infection. When the hospital water supply was heated to 60 degrees C and chlorinated, the nosocomial cases in the hospital completely disappeared.