scholarly journals Effect of essential oil on a biofilm of Staphylococcus aureus isolated from medical devices - in the university hospital of Tlemcen

2019 ◽  
Vol 12 (1) ◽  
pp. 122
Author(s):  
H. Hassaine ◽  
L. Ghellai ◽  
S. Bellifa ◽  
S. Gaouar ◽  
W. Didi
2020 ◽  
Vol 21 (4) ◽  
pp. 304-310
Author(s):  
I. Kara Terki ◽  
H. Hassaine ◽  
A. Kara Terki ◽  
B. Nadira ◽  
N. Kara Terki ◽  
...  

Background: Staphylococcus aureus is one of the species of bacteria most frequently isolated from medical devices. The ability to produce biofilm is an important step in the pathogenesis of these staphylococci infection, and biofilm formation is strongly dependent on environmental conditions as well as antibiotics and disinfectants used in the treatment and prevention of infections.Methodology: In this study, 28 S. aureus isolated from medical devices at the University Hospital Center of Sidi Bel Abbes in Northwestern Algeria were tested for biofilm formation by culture on Red Congo Agar (RCA). The tube method (TM) and tissue culture plate (TCP) techniques were also used to investigate the effect of penicillin, ethanol and betadine on pre-formed biofilm.Results: Nineteen S. aureus isolates produced biofilm on the RCA and 7 produced biofilms by the tube method, 2 of which were high producer. In addition, 9 S. aureus isolates produced biofilm on polystyrene micro-plates, and in the presence of penicillin and ethanol, this number increased to 19 and 11 biofilm producing S. aureus isolates respectively. On the other hand, no biofilm was formed in the presence of betadine.Conclusion: It is important to test for biofilm formation following an imposed external constraint such as disinfectants and antibiotics in order to develop new strategies to combat bacterial biofilms but also to better control their formation. Keywords : Staphylococcus aureus, biofilm, medical device, disinfectant, antibiotic French Title: Effets de certains désinfectants et antibiotiques sur la formation de biofilms par Staphylococcus aureus isolé à partir de dispositifs médicaux au Centre Hospitalier Universitaire de Sidi Bel Abbès, Algérie Contexte: Staphylococcus aureus est l'une des espèces de bactéries les plus fréquemment isolées des dispositifs médicaux. La capacité de produire du biofilm est une étape importante dans la pathogenèse de ces infections à staphylocoques, et la formation de biofilm dépend fortement des conditions environnementales ainsi que des antibiotiques et des désinfectants utilisés dans le traitement et la prévention des infections. Méthodologie: Dans cette étude, 28 S. aureus isolés à partir de dispositifs médicaux au Centre hospitalier universitaire de Sidi Bel Abbès dans le nord-ouest de l'Algérie ont été testés pour la formation de biofilm par culture sur gélose rouge du Congo (RCA). La méthode des tubes (TM) et les techniques de plaques de culture tissulaire (TCP) ont également été utilisées pour étudier l'effet de la pénicilline, de l'éthanol et de la bétadine sur le biofilm préformé. Résultats: Dix-neuf isolats de S. aureus ont produit un biofilm sur le RCA et 7 ont produit des biofilms par la méthode des tubes, dont 2 étaient très productifs. De plus, 9 isolats de S. aureus ont produit du biofilm sur des microplaques en polystyrène, et en présence de pénicilline et d'éthanol, ce nombre est passé à 19 et 11 isolats de S. aureus producteurs de biofilm respectivement. En revanche, aucun biofilm ne s'est formé en présence de bétadine. Conclusion: Il est important de tester la formation de biofilm suite à une contrainte externe imposée comme les désinfectants et les antibiotiques afin de développer de nouvelles stratégies pour lutter contre les biofilms bactériens mais aussi pour mieux contrôler leur formation. Mots-clés: Staphylococcus aureus, biofilm, dispositif médical, désinfectant, antibiotique  


2008 ◽  
Vol 57 (4) ◽  
pp. 403-410 ◽  
Author(s):  
P. Sauer ◽  
J. Síla ◽  
T. Štosová ◽  
R. Večeřová ◽  
P. Hejnar ◽  
...  

A rather fast and complicated progression of an infection caused by some strains of Staphylococcus aureus could be associated with the expression and co-action of virulence factor complexes in these strains. This study screened the antibiotic susceptibility and prevalence of virulence markers in isolates of meticillin-resistant S. aureus (MRSA) obtained from patients hospitalized at the University Hospital in Olomouc, Czech Republic. A total of 100 isolates was screened for 13 genes encoding extracellular virulence determinants (tst, pvl, eta, etb, sea, seb, sec, sed, see, seg, seh, sei and sej) and for their distribution in sample types. Eighty-nine isolates were positive for at least one of the genes. Genes for etb, pvl, see and seh were not detected in any of the MRSA isolates. No statistically significant differences in the occurrence of the determinants studied among sample types were found.


2013 ◽  
Vol 7 (49) ◽  
pp. 5558-5564 ◽  
Author(s):  
Bellifa Samia ◽  
Hassaine Hafida ◽  
Balestrino Damien ◽  
Charbonnel Nicolas ◽  
Mrsquo hamedi Imane ◽  
...  

2008 ◽  
Vol 57 (5) ◽  
pp. 612-616 ◽  
Author(s):  
Lukas Fenner ◽  
Andreas F. Widmer ◽  
Marc Dangel ◽  
Reno Frei

This study describes the distribution and frequencies of strain types by protein A-encoding gene (spa) typing among a total of 200 meticillin-resistant Staphylococcus aureus (MRSA) single-patient isolates collected between 2000 and 2005 at the University Hospital Basel, Switzerland. Nine frequent spa types accounted for 49.5 % of MRSA isolates, whereas spa type t041 (15 % of all isolates) belonged to a local epidemic strain that is also a common strain type in southern Germany. Successful control of the outbreak strain was documented by epidemiological data and confirmed by spa typing results. The spa type t044 (3.5 %), corresponding to a widely disseminated European community-acquired MRSA (CA-MRSA), was first observed in 2002. The well-known CA-MRSA USA300 clone was detected in four patients (2 %). Sporadic strains occurring less than four times (32 different spa types) accounted for 23 % of isolates. No predominant spa type was seen, indicating a great genetic diversity. Only 34.5 % of patient isolates were acquired nosocomially. The presence of one or more of ten common virulence genes was shown in 79 % of strains. It was demonstrated that the sequence-based spa typing method allows analysis of local MRSA epidemiology in relation to other regions and countries over time.


2021 ◽  
Author(s):  
Hyeokchan Kwon ◽  
Byungho Chung

UNSTRUCTURED Ransomware attacks, such as Conti, Ryuk, Petya, and Sodinokibi, that target medical institutions are increasing rapidly. In 2020, in the United States., ransomware attacks affected over 600 separate clinics, hospitals, and organizations, and more than 18 million patient records. The cost of these attacks is estimated to be almost $21 billion USD [1]. The first death related to ransomware attacks was reported by the University Hospital of Düsseldorf in Germany in 2020. The aim of this literature is to study vulnerabilities of cybersecurity in medical institutions, characteristics of ransomware aimed at medical institutions, and technical measures to prevent ransomware. From a security point of view, one of the most important targets of hackers against hospitals is medical devices. Many medical devices in hospitals are equipped with outdated software that is vulnerable to security and have many restrictions on security patches/updates. In addition, it is not easy to install even security functions such as antivirus due to the specificity of medical devices where availability is most important. As introduced in the Medjack report issued by TrapX Labs, in many cases, attackers target medical devices that are relatively insecure and then penetrate deep into more critical network infrastructure, such as EMR servers [2]. In this literature, we discuss various considerations to respond to ransomware while ensuring the availability of medical devices, and present AI-MDIPS (AI-based medical device intrusion prevention system) technology, a non-invasive and manageable security technology applicable to medical devices developed by the Korean government


2011 ◽  
Vol 56 (3) ◽  
pp. 1258-1264 ◽  
Author(s):  
Ilker Uçkay ◽  
Louis Bernard ◽  
Marta Buzzi ◽  
Stephan Harbarth ◽  
Patrice François ◽  
...  

ABSTRACTReduced susceptibility to glycopeptides in methicillin-resistantStaphylococcus aureus(MRSA) clinical isolates is considered a risk factor for failure of glycopeptide therapy. We compared the prevalences of MRSA isolates with reduced glycopeptide susceptibility in patients with versus without persistent or recurrent MRSA bloodstream infections. A retrospective cohort study at the University Hospital of Geneva identified 27 patients with persistent or recurrent clonally related MRSA bacteremic episodes over an 8-year period, which included 208 consecutive nosocomial MRSA bacteremic episodes. Vancomycin and teicoplanin MICs were determined by a modified macrodilution assay allowing improved detection of glycopeptide-intermediate MRSA isolates (GISA), characterized by elevated teicoplanin or/and vancomycin MICs (≥4 μg/ml). For 16 patients (59%), their pretherapy and/or posttherapy MRSA isolates showed elevated teicoplanin MICs, among which 10 (37%) concomitantly displayed elevated vancomycin MICs. In contrast, 11 other patients (41%) were persistently or recurrently infected with non-GISA isolates. In comparison, only 39 (22%) of 181 single isolates from patients with no microbiological evidence of persistent or recurrent infections showed elevated teicoplanin MICs, among which 14 (8%) concomitantly displayed elevated vancomycin MICs. Clinical, microbiological, and pharmacokinetic variables for patients persistently or recurrently infected with GISA or non-GISA isolates were similar. Bacteremic patients with a poor response to glycopeptide therapy had a 2.8-fold- and 4.8-fold-higher rates of MRSA isolates displaying elevated teicoplanin and vancomycin MICs, respectively, than patients with single isolates (P< 0.0001). Detection of elevated teicoplanin MICs may help to predict a poor response to glycopeptide therapy in MRSA bacteremic patients.


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