Introduktion: Vårdrelaterade infektioner, VRI:er, är ett stort hälsoproblem i Sverige. Genom att förebygga de undvikbara infektioner som drabbar patienter på våra sjukhus skulle vi kunna frigöra uppemot 200 000 vårddygn och 2,2 miljarder kronor per år. PVK:er står för en oklar del av dessa infektioner. Syfte: Syftet med studien var att undersöka vilka faktorer som kan påverka förekomsten av PVK-relaterade infektioner. Metod: en systematisk litteraturöversikt med kvalitativ ansats. Originalstudier som svarade mot studiens syfte söktes i databaserna Ci-nahl och Pubmed, med kriterier att de skulle vara publicerade de senaste 10 åren. Narrativ analys i form av koncentrering och kategorisering av resultatet med en sammanställning i text. Resultat: Tolv studier inkluderades i översikten. Huvudfynden kan sammanfattas som att klorhexidinsprit är bättre än povidonjod, injektionsmembran behöver desinfekteras för att kunna rekommenderas, heparin är inte bättre än natriumklorid för att förebygga komplikat-ioner, valet av förband påverkar inte komplikationsförekomsten och att PVK:er bör bytas på klinisk indikation. Slutsats: Det som genomgående lyfts i de inkluderade studierna är att det saknas underlag för att fastställa förekomsten av PVK-relaterad bakteriemi. Denna litteraturö-versikt visar att för att minska förekomsten av PVK-relaterade infektioner bör klorhexidinsprit användas som desinfektionsmedel och PVK:er bytas på klinisk indikation. Det som tydligt framkommit är att PVK-relaterade infektioner är ett understuderat ämne, det behövs stora stu-dier som mäter förekomsten av infektionerna för att sedan med ytterligare studier kunna mäta effekten av olika interventioner. / Introduction: Healthcare-associated infections, HAI’s, are a major health problem in Sweden. By preventing the avoidable infections that affect patients in our hospitals, we could free up to 200,000 care days and 2.2 billion SEK yearly. PVC’s account for an unclear proportion of these infections. Aim: The aim of the study was to investigate which factors may affect the occurrence of PVC-related infections. Method: a systematic literature review with a qualitative approach. Original studies that responded to the purpose of the study were searched in the data-bases Cinahl and Pubmed, with criteria that they should have been published in the last 10 years. Narrative analysis in the form of concentration and categorization of the results with a compilation in text. Results: Twelve studies were included in the review. The main findings can be summarized as that chlorhexidine alcohol is better than povidone-iodine, injection membranes need to be disinfected to be recommended, heparin is not better than sodium chloride for preventing complications, the choice of dressing does not affect the occurrence of compli-cations and that PVC’s should be changed on clinical indication. Conclusion: What is consistently highlighted in the included studies is that there is a lack of evidence to determine the occurrence of PVC-related bacteraemia. This literature review shows that in order to reduce PVC-related infections, chlorhexidine alcohol should be used as a disinfectant and that PVC’s are to be changed on clinical indication. What has clearly emerged is that PVC-related infections are an understudied topic, large studies are needed that measure the occurrence of the infections in order to then be able to measure the effect of various interventions with further studies.

Proteasomen, die die proteolytisch aktiven Untereinheiten LMP7, LMP2 und MECL1 inkorporieren, nennt man Immunoproteasomen. Während einer Immunreaktion führen diese regulierende sowie modulierende Funktionenaus. Sie sind konstitutiv exprimiert in Zellen hämatopoetischen Ursprungs, ein Bestandteil des angeborenen Immunsystems, die die erste Angriffsfront gegen pathogene Mikroorganismen ausbilden. Um die Bedeutung des Immunoproteasoms für die angeborene Immunantwort bei einer Streptococcus pneumoniae Infektion auf zu zeigen, charakterisierten wir den Krankheitsverlauf einer bakteriellen Pneumonie und analysierten lokale aber auch systemische Immunreaktionen in LMP7 ko Mäusen mit Hilfe eines S. pneumoniae Infektionsmodels. Die hier generierten Daten zeigten einen fortgeschrittenen Krankheitsverlauf in LMP7 ko Mäuse, der in einer systemischen inflammatorischen Immunreaktion endete und sich in klinischen Parametern, wie physiologische Kondition, spezifische diagnostische Marker und Immunsuppression, andeutete. Der Zustand der Sepsis entwickelte sich vermutlich aufgrund einer erhöhten bakteriellen Last im Blut und führte zu einer vorzeitigen Mortalität infizierter LMP7 ko Tiere. Obwohl die Fähigkeit von LMP7 ko Leukozyten ex vivo Bakterien zu eliminieren nicht beeinträchtigt war, zeigten LMP7 ko Mäuse in vivo eine verminderte Genexpression immunmodulierender Moleküle, wie Pentraxine, Fikoline und Kollektine. Diese Moleküle fördern die Aufnahme, Elimination und Degradation pathogener Mikroorganismen. Die reduzierte Expression opsonierender Moleküle wurde begleitet von einer veränderten proteasomalen Zusammensetzung in murinen Makrophagen und Lebergewebe. Zusammengefasst lässt sich sagen, dass diese Ergebnisse eine bisher unbekannte Rolle von Immunoproteasomalen Untereinheiten bei der Regulierung der angeborenen Immunantwort auf extrazelluläre bakterielle Infektionen unterstreichen. / Immunoproteasomes, harboring the active site subunits LMP7, LMP2, and MECL1 exert protective, regulatory or modulating functions during infection-induced immune responses. Immunoproteasomes are constitutively expressed in hematopoietic derived cells, constituting the first line of defense against invading pathogens. To clarify the impact of immunoproteasomes on the innate immune response against Streptococcus pneumoniae, we characterized the progression of disease and analyzed the local as well as systemic innate immune response in LMP7 ko mice by using a S. pneumoniae infection model. Data showed that mice deficient in LMP7 suffered from a more severe case of pneumonia which ended in a systemic inflammatory response indicated by aggravated clinical signs, diagnostic parameters, and immune suppression. The systemic inflammatory response probably established in consequence of an increased bacteremia and resulted in early mortality. Although, bacterial killing efficiency of LMP7 ko leukocytes was unaffected ex vivo, LMP7 ko mice exhibited a reduction in the transcription of genes encoding immune modulating molecules such as pentraxins, ficolins, and collectins, which facilitate opsonophagocytosis. The reduced expression of opsonins was accompanied by an affected subunit composition of proteasomes in murine macrophages and liver. In summary these results highlight an unsuspected role for immuno-subunits in modulating the innate immune response to extracellular bacterial infections.

La présence de bactéries dans le sang, un milieu normalement stérile, peut avoir des conséquences graves voire fatales pour l’organisme atteint. Afin de diagnostiquer au plus tôt cette infection, appelée bactériémie, et ainsi administrer le traitement adéquat, il est nécessaire d’identifier les microorganismes isolés à partir du sang. Mais, la nature complexe de ce fluide biologique, associée à la faible charge bactérienne, parfois inférieure à 1 UFC par millilitre de sang ont des conséquences sur les méthodes pouvant être utilisées pour l’identification des bactéries. La plupart d’entre elles ont donc recours à une première étape, l’hémoculture, au cours de laquelle les microorganismes présents dans le prélèvement sanguin de volume important (20-30 mL) vont se multiplier. Leur croissance est facilitée par la dilution du sang dans des milieux de culture dédiés à cette étape particulière. C’est seulement ensuite que l’identification peut débuter. Elle nécessite encore entre 2 et 48 heures et parfois plus, selon les moyens à disposition et les microorganismes impliqués. Réduire considérablement le temps nécessaire à l’identification aurait pourtant des retombées bénéfiques à l’échelle du patient mais aussi plus globalement en réduisant les coûts associés à cette infection et en limitant la pression de sélection exercée par l’emploi d’antibiotiques à large spectre.Au cours de ce travail, l’évaluation d’une stratégie basée sur l’identification des bactéries lors de leur multiplication dans le milieu d’hémoculture est donc proposée. Elle repose sur l’observation en temps réel et sans marquage par Résonance Plasmonique de Surface par imagerie (SPRi) des interactions entre les bactéries et des ligands déposés à la surface d’un capteur. Dans un premier temps, des ligands alternatifs aux anticorps parmi lesquels figurent les aptamères, des protéines de l’immunité innée et la vancomycine sont testés. Suite à cette étude, les anticorps ont été retenus pour poursuivre ce travail. Leur emploi n’est cependant pas dénué de difficultés lorsqu’il s’agit de détecter spécifiquement Staphylococcus aureus, choisi comme l’un des modèles expérimentaux. En effet, la présence de protéine A chez cette bactérie est à l’origine d’interférences sur les immunoglobulines. Différentes stratégies pour s’affranchir de ces effets ont été évaluées, comme le clivage enzymatique des anticorps ou l’emploi d’anticorps de poule pour lesquels la protéine A n’a pas d’affinité. Ces essais aboutissent à des résultats encourageants en milieu de culture simple. L’ajout de sérum humain au milieu a soulevé de nouveaux problèmes pour la détection de cette bactérie. Les résultats montrent qu’en interagissant avec des constituants de l’échantillon sanguin, dont les anticorps, S. aureus devient indétectable par une biopuce à anticorps. Une discussion des moyens possibles pour lever cette inhibition est ensuite proposée. Des expériences de détection d’une autre bactérie, Salmonella enterica sérovar Enteritidis pour laquelle nous disposons d’un anticorps hautement affin et spécifique ont alors été entreprises afin de conclure sur l’employabilité du dispositif dans des conditions proches d’une hémoculture. Des interférences affectant différentiellement les anticorps selon leur point isoélectrique ont ainsi été mises en évidences et l’implication de l’anticoagulant (polyanéthole sulfonate de sodium, SPS) présent dans les milieux d’hémoculture a été démontrée. La résolution partielle de ce problème a finalement permis la détection de 1 UFC.mL-1 de sang dans 32 mL au total démontrant ainsi la possibilité de détecter spécifiquement une bactérie dans des conditions proches d’une hémoculture. / The presence of bacteria in the blood, a normally sterile environment, can cause dramatic consequences for an organism. In order to diagnose this infection, called bacteremia, the identification of the microorganism present in blood must be performed. Furthermore, proper diagnosis enables the administration of a suitable antibiotic therapy. Blood complexity as well as the low bacterial load, usually lower than 1 CFU.mL-1, make the diagnosis of this infection quite challenging. Indeed, most identification methods begin only after the blood culture turns positive due to their insufficient sensitivity. For this they require incubation of a large blood sample volume (20 – 30 mL) in specific culture media that allows bacterial growth above their detection limit. Therefore, its increases considerably the time of diagnosis, which usually takes between 2 and 48 hours and sometimes even more time after blood culture positivity depending on the method and the microorganism present in blood. A reduction of the time required for identification would have a positive impact for both the patient and the healthcare systems by reducing selective pressure on resistant bacteria and hospitalization costs by giving proper treatment faster.In this work, the evaluation of a new strategy based on the identification of bacteria during their multiplication in the blood culture is presented. This method is based on Surface Plasmon Resonance imaging (SPRi) which enables real time and label-free measurements of interactions occurring between bacteria and specific probes. Alternative ligands like aptamers, innate immune proteins and vancomycin have been tested. Following this study antibodies have been chosen as the major specific probes in this work. Nonetheless, the presence of the staphylococcal protein A leads to false-positive results in all immunoglobulin G (IgG). Enzymatic cleavage to remove the constant fragment of antibody where protein A interacts and the use of chicken antibodies (IgY) for which protein A has no affinity have been evaluated. Both methods allow to get rid of protein A interactions in pure culture media. But the presence of human serum in the media results in the total loss of signal. Our results show that interactions between blood components and staphylococcal proteins exposed at the bacterial surface, including the interactions between protein A and circulating antibodies, are responsible for this phenomenon. Solutions to alleviate this inhibition are discussed and tested. Detection experiments of another bacterial model, Salmonella enterica serovar Enteritidis in blood culture media are presented. The crucial role played by the anticoagulant Sodium Polyanethole Sulfonate in non-specific interactions on antibodies is demonstrated. These interactions leading to a total loss of specificity for some antibodies are influenced by the isoelectric point (pI) of the probes which interact with this anionic compound and then attract blood components. After the partial resolution of this issue, we show the feasibility of detecting less than one bacteria per blood milliliter in a total volume of 32 milliliters, conditions close to real blood culture.

<p>Uvod: Infekcija krvi izazvana multirezistentnim bakterijama roda Acinetobacter (MDRA) je praćena značajnim letalitetom i visokim tro&scaron;kovima bolničkog lečenja. Ciljevi istraživanja: Ustanoviti uče&scaron;će izolata Acinetobacter spp. u strukturi pozitivnih hemokultura i kretanje procenta rezistencije na antibiotike u zdravstvenim ustanovama sekundarnog i tercijarnog nivoa na teritoriji AP Vojvodine u periodu 2013-2015. godina; Utvrditi kod kojih pacijenata se najče&scaron;će javljaju infekcije krvi izazvane MDRA; Utvrditi faktore rizika za nastanak bolničke infekcije (BI) krvi izazvane MDRA i uticaj BI krvi izazvane ovim uzročnicima na dužinu trajanja hospitalizacije i na ishod lečenja pacijenata hospitalizovanih u zdravstvenim ustanovama sekundarnog i tercijarnog nivoa u AP Vojvodini. Materijal i metode: Podaci iz protokola mikrobiolo&scaron;ke laboratorije Centra za mikrobiologiju Instituta za javno zdravlje Vojvodine su kori&scaron;teni za retrospektivnu analizu učestalosti izolata Acinetobacter spp. u strukturi hemokultura i za praćenje kretanja procenta rezistentnih izolata Acinetobacter spp. na posmatrane vrste antibiotika u zdravstvenim ustanovama sekundarnog i tercijarnog nivoa u AP Vojvodini u periodu od 01.01.2013. do 31.12.2015. godine. Utvrđivanje faktora rizika za nastanak infekcije krvi izazvane MDRA je sprovedeno kao prospektivna kohortna studija u jedinicama intenzivnih nega (JIN) u zdravstvenim ustanovama u AP Vojvodini u periodu od 01.01.2013. do 31.03.2016. godine. Grupu 1 (n=164), studijsku grupu kohortne studije su činili ispitanici sa BI krvi izazvanom MDRA. Grupu 2 (n=328), kontrolnu grupu kohortne studije, sačinjavali su pacijenti JIN bez izolata Acinetobacter spp. u hemokulturi. Kontrole su bile uključene u istraživanje samo ako je dužina njihovog boravka u JIN (dužina trajanja hospitalizacije do otpusta) bila ista ili duža od dužine boravka para iz studijske grupe do izolacije MDRA iz hemokulture. Kontrole su bile uparene sa slučajem iz studijske grupe u odnosu (1:2) prema: uzrastu (+/-5 godine), vrsti JIN i vremenu (isti kalendarski mesec u kojem je kod para iz studijske grupe izolovana pozitivna hemokultura). U cilju utvrđivanja predisponirajućih faktora za letalni ishod (14-dnevni letalitet) pacijenata u JIN sa infekcijom krvi izazvanom MDRA sprovedena je anamnestička studija. Rezultati: Uče&scaron;će izolata Acinetobacter spp. u strukturi hemokultura pacijenata uzrasta 18 i vi&scaron;e godina hospitalizovanih u zdravstvenim ustanovama u AP Vojvodini u periodu 2013-2015. godina iznosilo je 13,9%. Primoizolati Acinetobacter spp. iz uzoraka hemokultura pacijenata su u 96,1% (198/204) bili multirezistentni. Analizom kretanja rezistencije izolata Acinetobacter spp. na ispitivane antibiotike jedino je na cefepim ustanovljeno statistički značajno smanjenje uče&scaron;ća rezistentnih izolata (od 98,5% u 2014. godini do 83,3% u 2015. godini), (p=0,025). Izolati Acinetobacter spp. su najče&scaron;će registrovani kod pacijenata hospitalizovanih u JIN (71,1% (145/204)). Multivarijantnom analizom izdvojili su se nezavisni prediktori za nastanak infekcije krvi izazvane MDRA: prijem iz drugog odeljenja/bolnice, prijemne dijagnoze politrauma i opekotina, prethodna kolonizacija gornjeg respiratornog trakta MDRA, prisustvo dva i vi&scaron;e komorbiditeta, prethodna primena mehaničke ventilacije, vi&scaron;i indeks invazivnih procedura, prethodna primena derivata imidazola i prethodna primena četiri i vi&scaron;e klasa antibiotika. Pacijenti sa infekcijom krvi izazvanom MDRA su statistički značajno duže boravili u JIN (24.5&plusmn;17,5) u odnosu na neinficirane kontrole (19,7&plusmn;12,6), (p=0,001) i statistički značajno če&scaron;će su imali letalan ishod (51,2% (84/164) u odnosu na pacijente bez infekcije krvi izazvane ovim mikroorganizmom (25,0% (82/328), (p&lt;0,0001). Multivarijantnom analizom, kao nezavisni prediktori letalnog ishoda pacijenata, izdvojili su se: starija životna dob, prijemnom dijagnoza akutne respiratorne insuficijencije i primena neadekvatne antimikrobne terapije nakon izolacije uzročnika iz hemokulture. Zaključak: Učestalost i struktura faktora rizika je ukazala da je snižavanje prevalencije i snižavanje letaliteta moguće ostvariti kombinovanom primenom mera koje obuhvataju racionalnu upotrebu antibiotika &scaron;irokog spektra u empirijskoj antimikrobnoj terapiji i striktno po&scaron;tovanje procedura vezanih za primenu invazivnih nastavaka.</p> / <p>Aim: Establish the participation of Acinetobacter spp. isolates in the structure of positive hemocultures and the percentage range of resistance to antibiotics in the health institutions of secondary and tertiary level on the territory of AP of Vojvodina in the period from 2013 to 2015; determine which patients most commonly get BSI caused by MDRA; determine risk factors for the occurrence of healthcare-associated infection (HAI) of blood caused by MDRA and the impact of HAI of blood caused by these pathogens to the duration of hospitalization, and the treatment outcome of patients admitted to the health care institutions of secondary and tertiary levels in the AP of Vojvodina. Material and Methods: Data from the protocol of the microbiological laboratory of the Center for Microbiology, Institute of Public Health of Vojvodina were used for retrospective analysis of the frequency of isolates of Acinetobacter spp. in the structure of positive hemocultures and for monitoring the percentage isolates of Acinetobacter spp. resistant to the observed type of antibiotics in health institutions of secondary and tertiary levels in AP of Vojvodina in the period from January 1, 2013 to December 31, 2015. Determining the risk factor for the occurrence of BSI induced by MDRA was conducted as a prospective cohort study in intensive care units (ICU) in the health institutions in AP of Vojvodina in the period from January 1, 2013 to March 31, 2016. Group 1 (n=164), study group of the cohort study included the patients with HAI of blood induced by MDRA. Group 2 (n=328), control group of the cohort study consisted of ICU patients without isolates of Acinetobacter spp. in the hemoculture. Controls were included in the study only if the length of their stay in the ICU (duration of hospitalization until discharge) was the same or longer than the length of the stay of their study group counterparts until the isolation of MDRA from blood culture. Controls were matched with the cases of the study group in the ratio (1: 2) according to: age (+/- 5 years), type of ICU and time (the same calendar month in which positive hemoculture was isolated in the the study group pair). In order to determine the predisposing factors of lethal outcome (14-day lethality) of patients in the ICU with the BSI caused by MDRA, anamnestic study was conducted. Results: Participation of Acinetobacter spp. isolates in the structure of hemocultures of patients, aged 18 and older, hospitalized in medical institutions in AP of Vojvodina in the period from 2013 to 2015 amounted to 13.9%. Acinetobacter spp. primoisolates from the patients&#39; hemoculture samples were in 96.1% (198/204) multi-drug resistant. Analysing the Acinetobacter spp. isolates resistance to the tested antibiotics, Cefepime was the only to prove to cause statistically significant decrease in the share of resistant isolates (from 98.5% in the year 2014 to 83.3% in 2015), (p=0.025). Isolates of Acinetobacter spp. are most frequently registered in patients hospitalized in ICU (71.1% (145/204)). Multivariate analyses separated independent predictors for the occurrence of blood infection caused by the MDRA: patient transfers from another ward/hospital, admission diagnoses of polytrauma and burns, previous colonization of the upper respiratory tract MDRA, the presence of two or more co-morbidity, previous use of mechanical ventilation, higher index of invasive procedures, previous use of Imidazole derivates and the previous use of four or more classes of antibiotics. Patients with BSI caused by MDRA stayed statistically much longer in the ICU (24.5&plusmn;17.5) as compared to uninfected controls (19.7&plusmn;12.6), (p=0.001) and significantly more likely to have the lethal outcome (51.2% (84/164)) compared to patients without bloodsteram infections caused by this micro-organism (25.0% (82/328) (p&lt;0.0001). Using multivariate analysis, independent predictors of death of patients, were found to be: advanced age, admission diagnosis of acute respiratory insufficiency and the application of inadequate antibiotic therapy after the isolation of pathogens from the hemoculture. Conclusion: The frequency and the structure of the risk factors suggested that the reduction of the prevalence and lowering of lethality can be achieved by combined administration of measures that include the rational use of broad spectrum antibiotics in the empirical antimicrobial treatment and strict compliance with the procedures related to the use of invasive follow-ups.</p>

L’analyse microbiologique pour confirmer l’absence de bactéries dans des échantillons biologiques normalement sains, comme le sang, est une routine dans de nombreux laboratoires. En effet, la présence de bactéries dans le sang, appelée bactériémie, peut avoir des conséquences très graves, voire mortelles pour le patient. Le protocole standard pour la détection des bactériémies repose jusqu’ici sur l’enrichissement des échantillons sanguins prélevés sur les patients lors de l’hémoculture, afin d’obtenir une population suffisante pour analyse. La lenteur de ce procédé retarde ainsi de parfois plusieurs jours le diagnostic et donc l’adaptation du traitement antibiotique administré au patient. Ces dernières décennies, des techniques comme l’identification par spectrométrie de masse ou les analyses moléculaires, ont permis de diminuer le délai requis pour identifier les pathogènes en cause. Dans ce contexte, l’emploi de biocapteurs est également une alternative. Ce travail propose d’inclure des sondes à large spectre dans un capteur optique par imagerie SPR (résonance de plasmons de surface). Ce système est déjà développé pour la reconnaissance spécifique de pathogènes au cours de leur croissance dans le sang. Les nouveaux ligands proposés et évalués sont les peptides antimicrobiens (PAM). Ces courts peptides cationiques et amphiphiles, présentent l’avantage d’un large spectre d’interaction couplé à une haute stabilité (chimique, thermique et séchage) comparativement aux anticorps employés jusqu’ici. Leur immobilisation sur des prismes SPRI permet d’évaluer simultanément l’affinité de plusieurs PAM à la même souche bactérienne. Les biocapteurs ainsi préparés ont permis de détecter des souches pathogènes d’Escherichia coli et Staphylococcus aureus en milieu de culture simple, comme en plasma et en sang dilué au milieu d’hémoculture. Le système obtenu permet la détection des pathogènes présents à une concentration initiale de l’ordre de 1 UFC.ml-1, en moins de 24 heures et quel que soit le milieu. Enfin, la mise en place d’analyses statistiques multidimensionnelles a abouti à une classification cohérente des espèces ciblées en milieu simple, comme en sang. Ces résultats montrent le potentiel de ce système pour parvenir à développer un biocapteur à large spectre capable à la fois de détecter mais aussi d’identifier par affinité croisée des pathogènes bactériens. / Microbiological analysis to confirm the absence of bacteria in normally sterile biological samples, such as blood, is routine in many laboratories. The presence of bacteria in blood, called bacteremia, can have very serious, and even fatal consequences for the patient. So far, the standard protocol for their detection has been based on the enrichment of blood samples collected from patients, thanks to blood culture, in order to obtain a sufficient population for analysis. These procedures are time consuming which sometimes lead to delays in diagnosis and subsequent adaptation of antibiotic treatments by several days. In recent decades, techniques such as mass spectrometry identification or molecular analyses have reduced the time required to identify the pathogens involved. In this context, the use of biosensors is another promising alternative. This work proposes to include wide spectrum probes in an optical sensor using SPR imaging (surface plasmon resonance). This system is already developed for the specific recognition of pathogens during their growth in the blood. The new ligands we propose to evaluate are antimicrobial peptides (AMP). These short, cationic and amphiphilic peptides have the advantage of having a broad spectrum of interaction with bacteria, coupled with high stability (chemical, thermal and drying), especially compared to the antibodies used so far in this technique. Their immobilization on SPRI prisms allows the simultaneous evaluation of the affinity of several AMP to the same bacterial strain. The biosensors based on AMP were able to detect pathogenic strains of Escherichia coli and Staphylococcus aureus in simple culture medium, such as plasma and diluted blood in blood culture medium. The system obtained allows the detection of pathogens present at an initial concentration of about 1 CFU.ml-1, in less than 24 hours and in all assayed media. Finally, the implementation of multidimensional statistical analyses has resulted in a consistent classification of targeted species, in simple culture medium, such as blood. These results show the potential of this system to develop a wide-spectrum biosensor capable of both detecting and cross-referencing bacterial pathogens.

Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / O Staphylococcus aureus resistente a meticilina (MRSA) foi inicialmente descrito como um patógeno associado a infecções relacionadas à assistência em saúde; porém, um clone de MRSA, o CA-MRSA emergiu na comunidade e está atualmente incrementando nos hospitais. O objetivo desta tese foi descrever aspectos relacionados com a epidemiologia das infecções por cepas CA-MRSA no Hospital Universitário Pedro Ernesto da Universidade do Estado do Rio de Janeiro (HUPE/UERJ), avaliando especificamente fatores de risco relacionado com as infecções por CA-MRSA. Usando informações das bases de dados do laboratório de microbiologia, da farmácia e da Comissão para Controle da Infecção Hospitalar do HUPE/UERJ foi realizado um estudo retrospectivo de infecções/colonizações por cepas de S. aureus (fevereiro 2005 a Julho 2011). Foi realizado um estudo caso e controle, utilizando como casos os pacientes com infecções por cepas CA-MRSA. Na avaliação da susceptibilidade aos antimicrobianos usados em infecções graves por MRSA (vancomicina, teicoplanina, daptomicina e linezolida), foram determinadas as concentrações inibitórias mínimas (CIM) das amostras por diferentes metodologias (testes de difusão em agar, microdiluição em caldo e E-test). Nas analises das tendências temporais da apresentação dos subtipos de MRSA, usando um critério fenotípico para classificação das cepas MRSA, foi observada uma diminuição do número de cepas de MRSA multirresistente (HA-MRSA) (p<0.05). Também foi observada uma tendência ao aumento de cepas não-multirresistentes (CA-MRSA), mas sem alcançar a significância estatística (p = 0.06) igual que os S. aureus sensíveis a meticilina (MSSA) (p = 0.48). Não houve associação entre o subtipo de MRSA e a mortalidade devida à infecção por cepas MRSA. Uma idade acima de 70 anos (OR: 2.46, IC95%: 0.99 - 6.11), a presença de pneumonia adquirida no hospital (OR: 4.94, IC95%: 1.65 -14.8), a doença pulmonar obstrutiva crônica (OR: 6.09, IC95% 1.16 31.98) e a leucemia (OR: 8.2, IC95%: 1.25 54.7) foram fatores de risco associadas à mortalidade nas infecções por cepas de S. aureus. Usando curvas de Kaplan-Meier, foi observada uma tendência ao aumento da mortalidade em infecções causadas por MSSA na primeira semana, porém sem alcançar significância estatística (p = 0.07). Não foram observadas amostras MRSA com susceptibilidade intermediaria a vancomicina, linezolida, daptomicina ou teicoplanina. A dinâmica das infecções por S. aureus no HUPE/UERJ mudou durante o período de estudo, com menor número de episódios infecciosos causados por cepas de MRSA multirresistentes. Existe uma tendência ao aumento das cepas não-multirresistentes de MRSA entanto que a taxa de infecções por MSSA permaneceu estável no período do estudo. O perfil de resistência dos estafilococos não teve associação com a mortalidade / The methicillin-resistant Staphylococcus aureus (MRSA) was described initially like a health-care associated pathogen. However, an MRSA clone called community-adquired S. aureus emerged with success in the community and now has a worring increasing frequency in hospital settings. The aim of this study was to descript issues related to the epidemiology of infections due tu CA-MRSA isolates at the Pedro Ernesto Universitary Hospital (HUPE/UERJ) in Rio de Janeiro, Brazil from february 2005 to june 2011, analyzing risk factors related to these infections. Thus, using databases of the microbiology laboratory, pharmacia department and the infection control committee of the HUPE-UERJ, was realized an restrospective study of S. aureus isolates obtained from infected/colonizated patients hospitalized from February 2005 to July 2011. To evaluate risk factors related to CA-MRSA infections was conduced a case-control study, using patients with true infections due to MRSA like cases and patients with methicillin susceptible S. aureus (MSSA) like controls. To test the antimicrobial susceptibility of the antibiotics used in MRSA severe infections (Vancomycin, teicoplanin, daptomycin and linezolid), were determinated the minimal inhibitory concentration (MIC) of MRSA isolates using differents methods (disk-difusion test, microdilution in broth and E-test strips). The trend analyses of the MRSA types, using a phenotypic criteria to classificate the MRSA isolates, found a decrease in the infections due to multi-resistant MRSA isolates (HA-MRSA) in our hospital (p<0.05). Also was observed and increase in non-multi-resistant MRSA strains (CA-MRSA), but without reach statistic significancy (p = 0.06), similar to MSSA (p = 0.48). There is not association between the MRSA phenotype and the mortality due to S. aureus infection. In the multivariate analysis, were observed that an older age than 70 years (OR: 2.46, IC95%: 0.99 - 6.11), health-care pneumonia (OR: 4.94, IC95%: 1.65 -14.8), chronic obstructive pulmonary disease (OR: 6.09, IC95% 1.16 31.98) and leucaemia (OR: 8.2, IC95%: 1.25 54.7) were risk factors associated with mortality due to S. aureus infections. The Kaplan-Meier analysis, found a trend to high mortality due to MSSA infections in the first week, but without get statistic significancy (p = 0.07). We dont found any MRSA isolated with resistance or intermediary resistance to vancomycin, linezolid, daptomycin or teicoplanin. There is good correlation between both MICs determinations, with broth microdiluiton and E-Test strips metodhology. Its were concluded that the dynamic of the S. aureus infections at the HUPE/UERJ is changing, with less number of infectious episodes due to multi-resistant MRSA isolates. Moreover, there are an increasing number of infections due to non-multi-resistant MRSA isolate. The prevalence of infections due to MSSA dont have change in the time of period study. The kind of the S. aureus phenotype dont has association with all-causes-mortality

Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / O Staphylococcus aureus resistente a meticilina (MRSA) foi inicialmente descrito como um patógeno associado a infecções relacionadas à assistência em saúde; porém, um clone de MRSA, o CA-MRSA emergiu na comunidade e está atualmente incrementando nos hospitais. O objetivo desta tese foi descrever aspectos relacionados com a epidemiologia das infecções por cepas CA-MRSA no Hospital Universitário Pedro Ernesto da Universidade do Estado do Rio de Janeiro (HUPE/UERJ), avaliando especificamente fatores de risco relacionado com as infecções por CA-MRSA. Usando informações das bases de dados do laboratório de microbiologia, da farmácia e da Comissão para Controle da Infecção Hospitalar do HUPE/UERJ foi realizado um estudo retrospectivo de infecções/colonizações por cepas de S. aureus (fevereiro 2005 a Julho 2011). Foi realizado um estudo caso e controle, utilizando como casos os pacientes com infecções por cepas CA-MRSA. Na avaliação da susceptibilidade aos antimicrobianos usados em infecções graves por MRSA (vancomicina, teicoplanina, daptomicina e linezolida), foram determinadas as concentrações inibitórias mínimas (CIM) das amostras por diferentes metodologias (testes de difusão em agar, microdiluição em caldo e E-test). Nas analises das tendências temporais da apresentação dos subtipos de MRSA, usando um critério fenotípico para classificação das cepas MRSA, foi observada uma diminuição do número de cepas de MRSA multirresistente (HA-MRSA) (p<0.05). Também foi observada uma tendência ao aumento de cepas não-multirresistentes (CA-MRSA), mas sem alcançar a significância estatística (p = 0.06) igual que os S. aureus sensíveis a meticilina (MSSA) (p = 0.48). Não houve associação entre o subtipo de MRSA e a mortalidade devida à infecção por cepas MRSA. Uma idade acima de 70 anos (OR: 2.46, IC95%: 0.99 - 6.11), a presença de pneumonia adquirida no hospital (OR: 4.94, IC95%: 1.65 -14.8), a doença pulmonar obstrutiva crônica (OR: 6.09, IC95% 1.16 31.98) e a leucemia (OR: 8.2, IC95%: 1.25 54.7) foram fatores de risco associadas à mortalidade nas infecções por cepas de S. aureus. Usando curvas de Kaplan-Meier, foi observada uma tendência ao aumento da mortalidade em infecções causadas por MSSA na primeira semana, porém sem alcançar significância estatística (p = 0.07). Não foram observadas amostras MRSA com susceptibilidade intermediaria a vancomicina, linezolida, daptomicina ou teicoplanina. A dinâmica das infecções por S. aureus no HUPE/UERJ mudou durante o período de estudo, com menor número de episódios infecciosos causados por cepas de MRSA multirresistentes. Existe uma tendência ao aumento das cepas não-multirresistentes de MRSA entanto que a taxa de infecções por MSSA permaneceu estável no período do estudo. O perfil de resistência dos estafilococos não teve associação com a mortalidade / The methicillin-resistant Staphylococcus aureus (MRSA) was described initially like a health-care associated pathogen. However, an MRSA clone called community-adquired S. aureus emerged with success in the community and now has a worring increasing frequency in hospital settings. The aim of this study was to descript issues related to the epidemiology of infections due tu CA-MRSA isolates at the Pedro Ernesto Universitary Hospital (HUPE/UERJ) in Rio de Janeiro, Brazil from february 2005 to june 2011, analyzing risk factors related to these infections. Thus, using databases of the microbiology laboratory, pharmacia department and the infection control committee of the HUPE-UERJ, was realized an restrospective study of S. aureus isolates obtained from infected/colonizated patients hospitalized from February 2005 to July 2011. To evaluate risk factors related to CA-MRSA infections was conduced a case-control study, using patients with true infections due to MRSA like cases and patients with methicillin susceptible S. aureus (MSSA) like controls. To test the antimicrobial susceptibility of the antibiotics used in MRSA severe infections (Vancomycin, teicoplanin, daptomycin and linezolid), were determinated the minimal inhibitory concentration (MIC) of MRSA isolates using differents methods (disk-difusion test, microdilution in broth and E-test strips). The trend analyses of the MRSA types, using a phenotypic criteria to classificate the MRSA isolates, found a decrease in the infections due to multi-resistant MRSA isolates (HA-MRSA) in our hospital (p<0.05). Also was observed and increase in non-multi-resistant MRSA strains (CA-MRSA), but without reach statistic significancy (p = 0.06), similar to MSSA (p = 0.48). There is not association between the MRSA phenotype and the mortality due to S. aureus infection. In the multivariate analysis, were observed that an older age than 70 years (OR: 2.46, IC95%: 0.99 - 6.11), health-care pneumonia (OR: 4.94, IC95%: 1.65 -14.8), chronic obstructive pulmonary disease (OR: 6.09, IC95% 1.16 31.98) and leucaemia (OR: 8.2, IC95%: 1.25 54.7) were risk factors associated with mortality due to S. aureus infections. The Kaplan-Meier analysis, found a trend to high mortality due to MSSA infections in the first week, but without get statistic significancy (p = 0.07). We dont found any MRSA isolated with resistance or intermediary resistance to vancomycin, linezolid, daptomycin or teicoplanin. There is good correlation between both MICs determinations, with broth microdiluiton and E-Test strips metodhology. Its were concluded that the dynamic of the S. aureus infections at the HUPE/UERJ is changing, with less number of infectious episodes due to multi-resistant MRSA isolates. Moreover, there are an increasing number of infections due to non-multi-resistant MRSA isolate. The prevalence of infections due to MSSA dont have change in the time of period study. The kind of the S. aureus phenotype dont has association with all-causes-mortality

Detta projekt genomfördes på företaget Sangair som för närvarande utvecklar medicinsk utrustning för att behandla bakteriemi med ozon. Bakteriemi uppstår när bakterier hamnar i blodomloppet, vilket kan trigga sepsis och septisk chock, med potentiellt dödligt utfall om obehandlat. För närvarande används antibiotika för att behandla bakteriemi, men det ökande hotet med antibiotikaresistens världen över innebär att forskare behöver hitta nya vägar för att behandla bakteriemi. Som en del av Sangairs utveckling gjordes en undersökning för att se hur bakterier påverkas av ozon. Projektet syftade till att 1) utveckla en metod för att detektera lysering av bakterier och 2) använda metoden för att se om ozon hade lyserande effekt på model-organismen Escherichia coli. För att testa metoden transformerades stam BL21 av E. coli med en pUC-19 plasmid för att producera beta-galaktosidas. Proteinets aktivitet mättes sedan i sonikerade bakterier, vilket visade att det var en effekitiv metod för att lysera bakterier och sedan mäta aktiviteten. För att undersöka om ozon hade en lyserande effekt, och samtidigt bestämma om man kunde mäta protein fann man att det optimala experimentella upplägget var att använde en ozonkoncentration på 6 g/m3, ett gasflöde på 5 ml/min och ett vätskeflöde på 25 ml/min. Resultatet från studien indikerade att ozon har en lyserande effekt, men fler studier behövs göras för att verifiera resultatet. Man undersökte också om detektionen av Beta-galaktosidas kunde förbättras genom att tillsätta Bovin serumalbumin (BSA) för att inhibera resterande ozon i prover som annars skulle kunna inaktivera Beta-galaktosidas. Resultaten indikerade dock inte någon effekt. Som ett sista experiment mättes även endotoxiner som frigjordes vid behandling, och det visade sig att när bakterier behandlas med ozon frigörs lipopolysackarider (LPS) och peptidoglykaner, vilket också kan tyda på lysis. / This project was conducted at Sangair. The company is currently developing a medical device aimed at treating bacteremia with ozone. Bacteremia is a condition that occurs when bacteria enters the bloodstream, and can trigger sepsis and septic shock, potentially leading to death if untreated. Antibiotics have traditionally been the way to treat bacteremia, but the looming threat of antibiotic resistance worldwide threatens this way of treatment, and research into novel approaches to eradicate the bacteria needs to be done. As part of Sangairs development, an investigation was done to see how ozone interacts with bacteria. The project aimed to 1) develop a method to detect bacterial lysis and 2) use the method to detect if ozone had a lysing effect on the bacterial model organism Escherechia coli. To test the method, the BL21 strain of  E. coli was transformed with the pUC-19 plasmid to produce the reporter enzyme Beta-galactosidase. The Beta-galactosidase activity was then measured in a supernatant of sonicated bacteria, which confirmed the suitability of the method to detect bacteria cell lysis. To be able to see if ozone had a lysing effect, while still being able to measure Beta-galactosidase, it was found that the optimal setup for this was using an ozone concentration of 6 g/m3, a gas flow of 5 ml/min and a liquid flow of 25 ml/min. The results acquired with this setup indicated that ozone had a lysing effect on E. coli but more studies are needed to verify this. It was further investigated if Beta-galactosidase detection could be improved by addition of bovine serum albumin (BSA) to quench residual ozone in the samples, but the results showed that it did not have any effect on the Beta-galactosidase enzymatic activity. As a final experiment, endotoxins that were released upon treatment were also measured, and it was found that when bacteria are treated with ozone, lipopolysaccharides (LPS) and peptidoglycans are released, further confirming lysis of the bacterial cells.