Bakgrunn: Blodbaneinfeksjon er en av de alvorligste sykehusinfeksjonene pasienter kan utsettes for, og i intensivavdelingen rammes de mest sårbare pasientene. Målet med studien:Å finne insidensen av blodbaneinfeksjoner (BSI) i en intensivavdeling i et lokalsykehus i Norge, samt undersøke ulike risikofaktorer knyttet til Centrale Venekatetre (CVK) og generell infeksjon ved innleggelse i intensivavdelingen. Metode: Insidensregistrering av BSI i løpet av 12 mnd. der definisjoner av BSI bygger på 2001 International Sepsis Definition Conference. Data er samlet inn prospektivt etter hvert som pasientene ble lagt. Studiepopulasjonen er antallet pasienter som hadde vært innlagt i mer enn 48 timer i intensivavdelingen, og deles opp i tre åpne kohorter:Pasienter med diagnostisert BSI i løpet av oppholdet, pasienter som fikk lagt inn CVK og pasienter med infeksjon ved innleggelse. Resultater: 615 pasienter ble lagt inn i intensivavdelingen i løpet av 12 mnd, av disse ble 116 av de pasientene som hadde vært innlagt i intensivavdelingen i mer enn 48 timer inkludert i studien. Gjennomsnittlig liggetid i intensivavdelingen varierte fra 2 til 40 (median 4 dager). 73 av de 116 pasientene fikk lagt inn CVK, og av disse fikk 11 en bekreftet BSI. Tre pasienter uten CVK fikk bekreftet BSI, totalt 14. Av disse 14 var 6 nosokomiale, altså 5,2 % (6 av 116) eller 7,8 BSI/1000 pasientdøgn. Enpasient fikk diagnosen kateter-relatert BSI(CR-BSI), noe som tilsvarer 1,7 CR-BSI/1000 kateterdøgn. Det ble tatt totalt 69 blodkulturer, herav 54 fra pasienter med CVK. Pasienter med CVK har signifikant større risiko for å utvikle klinisk BSI, enn de utenCVK (OR=5,31; 95 % CI 2,32 –12,0; p&lt; 0,0001). Konklusjon: Denne studien viser en relativt lav forekomsten av BSI, NBSI og CR-BSI, men for å kunne sammenligne tall nasjonalt og internasjonalt er det behov for en consensus i fagmiljøet rundt definisjoner BSI og særlig CR-BSI. Det er signifikant sammenheng mellom CVK og utvikling av klinisk BSI, men studien viser ingen signifikant sammenheng mellom CVK og bekreftet BSI. Studien bør bidra til fokus på risikofaktorene knyttet til bruk av CVK, samt arbeid for consensus angående definisjoner og økt fokus på CR-BSI og klinisk BSI, siden dette har vist seg å ha like høy letalitet som bekreftet BSI / Background: BSIs is areof the most serious hospital infections patients are exposed to, and in the intensive care unit (ICU) it affects the most vulnerable patients. Aim: To find the incidence of BSI in an ICU in a local hospital in Norway, as well as examine the various risk factors related to Central venous catheters (CVK), as well as patients with general infection at point of admission. Method: Incidence registration of BSIs within 12 months, where the definitions of BSI is based upon the 2001 Sepsis Definition Conference. Data is collected prospectively as patients were admitted to the ICU. The study population is the number of patients who had been hospitalized for more than 48 hours in the ICU, and the study population is divided into three open cohorts.Patients with diagnosed BSI during their stay, patients with CVK during stay and patients with infection at admission. Results: 615 patients were in the ICU within 12 months, and 116 of those patients had been hospitalized for more than 48 hours in the ICU and were included in the study. Average length of stay ranged from 2 to 40 days (median 4 days). 73 of the 116 patients had CVK in place during their stay, andof these 11 had a laboratory confirmed BSI. Three patients without any central CVK in place during their stay in the ICU had a laboratory confirmed BSI, 14 in total. Of these 14, 6 weredefined nosocomial, i.e.5.2% (6 of 116) or 7.8 BSI/1,000 patient days. One patient was diagnosed with catheter-related BSI (CR-BSI), which corresponds to 1.7 CR-BSI/1, 000 catheter days. A total of 69 blood cultures were performed, of which 54 patients with CVK. Patients with CVK has a significantly higher risk of developing clinical BSI than those without CVK (OR = 5.3, 95% CI 2.32 to 12.0, p &lt; 0.0001). Conclusion: This study shows a relatively low incidence of BSI, NBSI and CR-BSI. CVK is significantly related to the development of clinical BSI, but the study shows no link between CVK and laboratory confirmed BSI. This study may encourage health care  workers to focus more on the risk factors associated with the use of CVK to critically ill patients. It should also encourage researchers to focus more on the importance of consensus regarding definitions of BSI and clinical BSI, since this have been proven to have as high lethality rates as laboratory confirmed BSI / <p>ISBN 978-91-86739-86-7</p>

Abstract In Oulu University Hospital Haematological Ward during the years 1990–1991, a manual blood culture system was able to detect bloodstream infection (BSI) in 23% of febrile episodes of patients with acute myeloid leukaemia (AML), whereas during the years 1992–1993 an automated continuous-monitoring blood culture system (CMBCS) BacT/Alert® detected BSI in 40% of febrile episodes (p = 0.043). During the years 1997–2003, regimens containing high-dose cytarabine predisposed patients to laboratory-confirmed BSI (LCBI) with an odds ratio (OR) of 2.3 (with 95% confidence interval (CI) from 1.2 to 4.2). The LCBI risk was lowest after thioguanine-containing regimens (OR 0.26, 95% CI; 0.12–0.58). In the register data (years 1992–2006) from the prospective multi-centre AML -92 trial, when compared to cycle I, the OR for LCBI was significantly higher (from 4.8 to 5.8) in subsequent cycles (p &lt; 0.001). In all, 67% of mortality due to BSI occurred in patients with active leukaemia. An inoculum of microorganisms to produce 10 colony-forming units (cfu)/ml of 10 gram-positive coccal strains, 10 gram-negative bacillar strains and 8 Candida yeast strains was cultured in BacT/Alert® blood culture bottles in the presence of several chemotherapeutic drugs. Of the chemotherapeutic drugs tested, the anthracyclines exhibited inhibitory effects on the growth of microorganisms in concentrations corresponding to the therapeutic levels. In the standard bottles, doxorubicin increased the incubation time of gram-positive cocci and idarubicin increased the incubation time of Candida glabrata. However, no increase in the incubation time of any microbes was detected in the antimicrobial-neutralizing FAN bottles. In conclusion, the use of CMBCSs has resulted in an increased LCBI rate in neutropenic AML patients. In general, chemotherapeutic agents have no significant inhibitory effects on the growth of common microbial pathogens in blood culture. The detection of some difficult-to-culture microbial strains – C. glabrata for example – in blood cultures may be impaired by the presence of chemotherapeutics in blood. The chemotherapeutics may also affect the LCBI rate in other ways. As a predictor of adverse outcome of infection, the presence of active leukaemia is more important than the type of chemotherapy being administered.

Springer and European Journal of Clinical Microbiology and Infectious Diseases, 33, 2014, 1371-79, Seasonal trend and clinical presentation of Bacillus cereus bloodstream infection: association with summer and indwelling catheter, K. Kato & Y. Matsumura & M. Yamamoto & M. Nagao & Y. Ito & S. Takakura & S. Ichiyama, figure number 2, original copyright notice is given to the publication in which the material was originally published, by adding; with kind permission from Springer Science and Business Media / 京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第19922号 / 医博第4142号 / 新制||医||1017(附属図書館) / 33008 / 京都大学大学院医学研究科医学専攻 / (主査)教授 中川 一路, 教授 佐藤 俊哉, 教授 玉木 敬二 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Background: Bloodstream infection (BSI) caused by Klebsiella pneumoniae (KP), is a leading cause of hospitalassociated childhood mortality. There are limited data on how poor outcomes of KPBSI can be predicted in poorly resourced areas. This study aimed to assess if the profile of differential counts from full blood counts (FBC) taken at two time points in children <13 years with KPBSI could be used to predict the risk of death. Methods We conducted a retrospective study of a cohort of children admitted to hospital between 2006-2011 with KPBSI. FBC collected within 48 hours (T1) of blood culture and 5-14 days later (T2), were reviewed. Differential counts were classified as abnormal if they were higher or lower than laboratory ranges for normal results. The risk of death was assessed for each category of differential counts. Risk ratios adjusted (aRR) for potential confounders were used to estimate the effect of cell counts on risk of death using multivariable analysis. Data were stratified by HIV status. Results: Of 296 children included, median age 5 (IQR:2-13) months, 82 were HIV -infected. Ninety-five (32%) of the children with KPBSI died. Mortality in HIV-infected and uninfected children was 39/82 (48%) and 56/214 (26%), respectively (p <0.001). Independent associations with mortality were observed with leucopenia, neutropenia and thrombocytopenia. Risk of mortality in children with thrombocytopenia at T1 and T2 was aRR 2.5 (95% CI: 1.34-4.64) and 3.18 (95% CI: 1.31-7.73) respectively in the HIV-uninfected group, whereas the risk for mortality in the HIV-infected group with thrombocytopaenia at T1 and T2 was aRR 1.99 (95% CI: 0.94-4.19) and 2.01 (95% CI: 0.65-5.99) respectively. Neutropenia in the HIV-uninfected group at T1 and T2, showed aRR 2.17 (95% CI: 1.22- 3.88) and 3.70 (95% CI 1.30-10.51) respectively, while in the HIV-infected group, they were aRR 1.18 (95% CI 0.69-2.03) and 2.05 (0.87-4.85) at similar time points. Risk of mortality related to leucopenia at T2 was associated with mortality in HIV-uninfected and HIV-infected patients was aRR 3.22 (95%CI 1.22-8.51) and 2.34 (1.09-5.04) respectively. Persistently high band cell percentage at T2 in HIVinfected children indicated a risk of mortality of aRR 2.91 (95% CI 1.20-7.06). Conclusion Abnormal neutrophil counts and thrombocytopenia are independently associated with significant mortality in children with KPBSI. In resource-limited countries haematological markers have the potential to predict KPBSI mortality.

Ethanol lock therapy is a novel technique that is being studied for its efficacy in eradicating catheter related bloodstream infections. A systematic review of interdisciplinary studies from CINAHL, Medline, Academic Search Premier, Biological Abstracts, and Web of Knowledge databases was performed. This meta-analysis examined the findings of thirty-five studies on ethanol lock therapy. Twenty-six of these studies compared ethanol to a placebo and nine studies performed a direct comparison of ethanol to other agents frequently used in antimicrobial lock technique. Ethanol lock therapy was shown to be effective as both a prophylactic therapy and as an active treatment in eradicating biofilms of organisms that frequently cause catheter-related blood stream infections, including Staphylococcus epidermis, Staphylococcus aureus, Klebsiella pneumonia, Pseudomonas aeruginosa, E. coli, and Candida albicans. Ethanol has been shown to have a synergistic effect with several other antimicrobial agents. The majority of studies examined in this thesis have found that ethanol has equal or greater efficacy to several antibiotic and antimicrobial agents used in practice and should therefore be considered for the treatment of catheter-related blood stream infections.

Monocytic human leukocyte antigen-D related (mHLA-DR) expression determined by flow cytometry has been suggested as a biomarker of sepsisinduced immunosuppression. In order to facilitate use of HLA-DR in clinical practice, a quantitative real-time PCR technique measuring HLA-DR at the transcription level was developed and evalutated. Levels of HLA-DR mRNA correlated to mHLADR expression and were robustly measured, with high reproducibility, during the course of infection. Dynamics of mHLA-DR expression was studied during the first weeks of bloodstream infection (BSI) and was found to be dependent on the bacterial etiology of BSI. Moreover, mHLA-DR was shown to be inversely related to markers of inflammation. In patients with unfavourable outcome, sustained high C-reactive protein level and high neutrophil count were demonstrated along with low mHLA-DR expression and low lymphocyte count. This supports the theory of sustained inflammation in sepsis-induced immunosuppression. The association between mHLA-DR and bacterial etiology may be linked to the clinical trajectory via differences in ability to cause intractable infection. Staphylococcus aureus was the dominating etiology among cases with unfavourable outcome. With focus on patients with S. aureus BSI, those with complicated S. aureus BSI were found to have lower HLA-DR mRNA expression during the first week than those with uncomplicated S. aureus BSI. If these results can be confirmed in a larger cohort, HLA-DR measurement could possibly become an additional tool for early identification of patients who require further investigation to clear infectious foci and achieve source control. In conclusion, PCR-based measurement of HLA-DR is a promising method for measurements of the immune state in BSI, but needs further evaluation in the intensive care unit setting to define the predictive and prognostic value for deleterious immunosuppression. The etiology of infection should be taken into consideration in future studies of translational immunology in sepsis.

Os conectores sem agulhas foram introduzidos para redução de incidência de acidentes pérfuro-cortantes nos profissionais da área da saúde e a literatura apresenta evidências irrefutáveis sobre este aspecto. No entanto, não há evidências conclusivas sobre as vantagens do conector sem agulha para o paciente, no que se referem aos índices de infecção de corrente sanguínea relacionada ao cateter venoso central. Este estudo tem como objetivo evidenciar o impacto do uso de conectores sem agulhas para sistema fechado de infusão na ocorrência de infecção de corrente sanguínea relacionada ao cateter venoso central por meio de revisão sistemática, desenvolvida conforme as recomendações propostas pela Colaboração Cochrane. A estratégia de busca nas bases de dados eletrônicas utilizou os componentes do PICO: População (estudos com pacientes em uso de cateter venoso central, independente de idade, sexo, etnia e serviço de saúde vinculado); Intervenção (uso de conectores de sistema fechado sem agulhas, não-valvulados, valvulados, com pressão positiva ou não); Comparação (uso de oclusores, conectores de sistema fechado com ou sem agulhas, não-valvulados, valvulados, com pressão positiva ou não); Outcome-desfecho (infecção de corrente sanguínea, contaminação do canhão, contaminação microbiana, infecção de corrente sanguínea relacionada ao cateter). As bases eletrônicas investigadas foram: PubMEDLINE, OVID, EMBASE, LILACS, CINAHL. Também foram avaliadas as referências bibliográficas dos estudos incluídos. Os resultados estão apresentados em três etapas: caracterização do processo de seleção dos estudos encontrados na busca; caracterização dos estudos incluídos para a revisão sistemática (RS); avaliação de qualidade e força da evidência dos estudos incluídos segundo a Escala de Jadad e a Escala de avaliação de qualidade dos estudos na área de Controle e Prevenção de Infecção de Corrente Sanguínea Relacionada ao cateter Venoso Central. A amostra desta revisão sistemática constitui-se de 14 estudos, e quatro investigaram somente conectores sem agulhas. Foram encontrados 6 ensaios clínicos controlados randomizados, 4 coortes, 3 caso-controle e 1 resultado terapêutico. A infecção de corrente sanguínea relacionada ao cateter venoso central foi o desfecho de 9 estudos. Seis apresentaram diferenças a favor do conector valvulado; 04 a favor do conector puncionável com cânula; 01 a favor do conector puncionável com agulha; 01 a favor do conector valvulado com pressão positiva e 02 a favor do dispositivo usado antes da troca. A heterogeneidade dos estudos quanto aos desenhos de pesquisa, as características das populações e os fatores de riscos controlados e os resultados, não permitem a realização de meta-análise, contudo, é possível afirmar, com base nos quatro melhores estudos encontrados, que a implantação de conectores sem agulhas, quer valvulados ou com injetor pré-furado, com manutenção de sistema fechado de infusão, apresentam impacto positivo relacionado à menor contaminação do canhão do cateter ou na ocorrência de infecção de corrente sanguínea relacionada ao cateter venoso central / Needleless connectors were introduced to reduce the incidence of needlestick injuries in health professionals and according to the literature their effectiveness is irrefutable. However, there is no conclusive evidence on the advantages of needleless connectors for patients with regard to bloodstream infection rates from the use of central venous catheters. The objective of this study was to determine the impact of the use of needleless connectors in closed infusion systems on the occurrence of bloodstream infections related to the use of central venous catheters by conducting a Cochrane systematic review. The strategy for searching electronic databases employed the components of the PICO model: Population (studies of patients using central venous catheters, regardless of age, sex, race and associated health service); Intervention (use of closed needleless connector systems, with and without valves, with and without positive pressure); Comparison (use of plugs, closed system connectors with and without needles, with and without valves, with and without positive pressure); Outcome (bloodstream infection, cannula contamination, microbial contamination, bloodstream infection related to catheter). The electronic databases investigated were: PubMEDLINE, OVID, EMBASE, LILACS and CINAHL. Bibliographical references of the studies included were also evaluated. The results are presented in three stages: characterization of selection process for studies found in the search; characterization of studies included in the systematic revision; evaluation of quality and strength of evidence for studies included according to the Jadad Scale and the scale of quality of studies in the control and prevention of bloodstream infections related to central venous catheters. The sample of this systematic review was made up of 14 studies of which 4 investigated only needleless connectors. We found 6 randomized control clinical trials, 4 cohort, 3 case-control and 1 therapeutic result. Bloodstream infection related to central venous catheters was the outcome for 9 studies. Six presented differences regarding the valved connector; 04 in favor of the puncturable connector with cannula; 01 in favor of the puncturable connector with needle; 01 in favor of the valved connector with positive pressure and 02 in favor of the device used before the change. The heterogeneous nature of the studies with regard to design, population characteristics and controlled risk factors and results prevented a meta-analysis. However, it is possible to state, based on the four best studies found, that the introduction of needleless connectors, whether valved or puncturable with cannula, coupled with a closed infusion system, presented a positive impact on lowering contamination of catheter cannulae and on the occurrence of bloodstream infection related to central venous catheters

The aim of this study was to determine the prevalence of extended-spectrum b-lactamase (ESBL)- producing Klebsiella pneumoniae isolated from urinary tract and bloodstream infections in a rural hospital in Manhic¸a, Mozambique. ESBLs were investigated among ceftriaxone-non-susceptible K. pneumoniae clinical isolates recovered between 2004 and 2009. Characterisation of blaCTX-M, blaSHV, blaOXA and blaTEM genes was performed by PCR and sequencing. Epidemiological relationships were established by phylogenetic analysis, repetitive extragenic palindromic PCR (REP-PCR), pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST), whilst plasmid transferability was evaluated by conjugation. In addition,the presence of class 1 and 2 integrons was studied.A total of 19 K. pneumoniae were analysed. The blaCTX-M-15 gene was found in all strains. Other ESBL genes were found concomitantly, including blaSHV-5, blaSHV-2, blaSHV-2A, blaSHV-12 and blaSHV-38. In addition, other b-lactamases such as blaTEM-1 and blaOXA-30 were also detected. REP-PCR identified 15 different epidemiological profiles. MLST analysis also showed great variability of sequence types. The blaCTX-M-15 gene showed a high transfer capacity. The presence of class 1 integrons was high. High levels of multidrug resistance were also found. In conclusion, these data show the dominance of the CTX-M-type ESBL, particularly CTX-M-15, supporting its worldwide dissemination, including in areas with limited access to third-generation cephalosporins. This finding is a matter of concern for clinical management as third-generation cephalosporins are an alternative for treating severe cases of multidrug-resistant infections in this community. / Revisión por pares

Made available in DSpace on 2014-09-24T12:58:57Z (GMT). No. of bitstreams: 2 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Tese Liliane Miyuki Seki.pdf: 11573378 bytes, checksum: 779d1d4b49bfc191eafe332410d9730b (MD5) Previous issue date: 2012 / Enterobactérias produtoras de p-Iactamases de espectro estendido (ESBL) e Klebsiella pneumoniae carbapenemase (KPC) são reconhecidas mundialmente como importantes problemasde resistência bacteriana nos hospitais. Neste estudo, foi avaliada a prevalência dos genes codificadores de ESBL, bem como a epidemiologia molecular em isolados de hemocultura,em enterobactérias coletadas entre Setembro de 2007 a Setembro de 2008, em cincohospitais localizados no Estado do Rio de Janeiro, Brasil. Das 293 amostras coletadas, 121 foram caracterizadas fenotipicamente como produtores de ESBL sendo a maior prevalência de Klebsiella pneumoniae 63 (52,1%), Enterobacter cloacae 16 (13,2%), Escherichia coli 14 (11,6%), Proteus mtrabtlis 11 (9,1%), Serra tia marcescens 10 (8.3%), Morganella morganii 2 (1.7%), Enterobacter aerogenes 1 (0,8%), Klebsiella oxytoca 1 (0,8%), Providencia stuartii 1 (0,8%), Citrobacter freundii 1 (0,8%), Serratia rubidaea 1 (0,8%). Entre as produtoras de ESBL, 11 amostras de K. pneumoniae e 9 amostras de E cloacae mostraram resistência ou redução de susceptibilidade a pelo menos um dos carbapenemas. A detecção por PCR dos genes de p-Iactamase mostraram que 87,6% produziramblacTX_M, 65,3% blaTEM, 64,5% blaSHVe 9,1% blaxsc- O gene do grupo CTX-M-l foi predominante na maioria das espécies de enterobactérias, exceto para o P. mirabilis, onde 91% das amostras eram do gene do grupo CTX-M-2. Das amostras pertencentes ao grupo CTX-M-l, 88% das K. pneumoniae e 100% das Ecoli foram determinadas como CTX-M-15. A análise do polimorfismo genético, por PFGE, demonstrou a disseminação do gene CTX-M-15 em 10 genótipos para as amostras de K. pneumoniae e de 3 genótipos para Eco/i em diversos hospitais no Rio de Janeiro. (AU)

Os conectores sem agulhas foram introduzidos para redução de incidência de acidentes pérfuro-cortantes nos profissionais da área da saúde e a literatura apresenta evidências irrefutáveis sobre este aspecto. No entanto, não há evidências conclusivas sobre as vantagens do conector sem agulha para o paciente, no que se referem aos índices de infecção de corrente sanguínea relacionada ao cateter venoso central. Este estudo tem como objetivo evidenciar o impacto do uso de conectores sem agulhas para sistema fechado de infusão na ocorrência de infecção de corrente sanguínea relacionada ao cateter venoso central por meio de revisão sistemática, desenvolvida conforme as recomendações propostas pela Colaboração Cochrane. A estratégia de busca nas bases de dados eletrônicas utilizou os componentes do PICO: População (estudos com pacientes em uso de cateter venoso central, independente de idade, sexo, etnia e serviço de saúde vinculado); Intervenção (uso de conectores de sistema fechado sem agulhas, não-valvulados, valvulados, com pressão positiva ou não); Comparação (uso de oclusores, conectores de sistema fechado com ou sem agulhas, não-valvulados, valvulados, com pressão positiva ou não); Outcome-desfecho (infecção de corrente sanguínea, contaminação do canhão, contaminação microbiana, infecção de corrente sanguínea relacionada ao cateter). As bases eletrônicas investigadas foram: PubMEDLINE, OVID, EMBASE, LILACS, CINAHL. Também foram avaliadas as referências bibliográficas dos estudos incluídos. Os resultados estão apresentados em três etapas: caracterização do processo de seleção dos estudos encontrados na busca; caracterização dos estudos incluídos para a revisão sistemática (RS); avaliação de qualidade e força da evidência dos estudos incluídos segundo a Escala de Jadad e a Escala de avaliação de qualidade dos estudos na área de Controle e Prevenção de Infecção de Corrente Sanguínea Relacionada ao cateter Venoso Central. A amostra desta revisão sistemática constitui-se de 14 estudos, e quatro investigaram somente conectores sem agulhas. Foram encontrados 6 ensaios clínicos controlados randomizados, 4 coortes, 3 caso-controle e 1 resultado terapêutico. A infecção de corrente sanguínea relacionada ao cateter venoso central foi o desfecho de 9 estudos. Seis apresentaram diferenças a favor do conector valvulado; 04 a favor do conector puncionável com cânula; 01 a favor do conector puncionável com agulha; 01 a favor do conector valvulado com pressão positiva e 02 a favor do dispositivo usado antes da troca. A heterogeneidade dos estudos quanto aos desenhos de pesquisa, as características das populações e os fatores de riscos controlados e os resultados, não permitem a realização de meta-análise, contudo, é possível afirmar, com base nos quatro melhores estudos encontrados, que a implantação de conectores sem agulhas, quer valvulados ou com injetor pré-furado, com manutenção de sistema fechado de infusão, apresentam impacto positivo relacionado à menor contaminação do canhão do cateter ou na ocorrência de infecção de corrente sanguínea relacionada ao cateter venoso central / Needleless connectors were introduced to reduce the incidence of needlestick injuries in health professionals and according to the literature their effectiveness is irrefutable. However, there is no conclusive evidence on the advantages of needleless connectors for patients with regard to bloodstream infection rates from the use of central venous catheters. The objective of this study was to determine the impact of the use of needleless connectors in closed infusion systems on the occurrence of bloodstream infections related to the use of central venous catheters by conducting a Cochrane systematic review. The strategy for searching electronic databases employed the components of the PICO model: Population (studies of patients using central venous catheters, regardless of age, sex, race and associated health service); Intervention (use of closed needleless connector systems, with and without valves, with and without positive pressure); Comparison (use of plugs, closed system connectors with and without needles, with and without valves, with and without positive pressure); Outcome (bloodstream infection, cannula contamination, microbial contamination, bloodstream infection related to catheter). The electronic databases investigated were: PubMEDLINE, OVID, EMBASE, LILACS and CINAHL. Bibliographical references of the studies included were also evaluated. The results are presented in three stages: characterization of selection process for studies found in the search; characterization of studies included in the systematic revision; evaluation of quality and strength of evidence for studies included according to the Jadad Scale and the scale of quality of studies in the control and prevention of bloodstream infections related to central venous catheters. The sample of this systematic review was made up of 14 studies of which 4 investigated only needleless connectors. We found 6 randomized control clinical trials, 4 cohort, 3 case-control and 1 therapeutic result. Bloodstream infection related to central venous catheters was the outcome for 9 studies. Six presented differences regarding the valved connector; 04 in favor of the puncturable connector with cannula; 01 in favor of the puncturable connector with needle; 01 in favor of the valved connector with positive pressure and 02 in favor of the device used before the change. The heterogeneous nature of the studies with regard to design, population characteristics and controlled risk factors and results prevented a meta-analysis. However, it is possible to state, based on the four best studies found, that the introduction of needleless connectors, whether valved or puncturable with cannula, coupled with a closed infusion system, presented a positive impact on lowering contamination of catheter cannulae and on the occurrence of bloodstream infection related to central venous catheters