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Dansk Selskab for Infektionsmedicin
Nyt fra tidsskrifterneSidst opdateret 24.11.2018 Direkte link
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1 [Articles] Cefiderocol versus imipenem-cilastatin for the treatment of complicated urinary tract infections caused by Gram-negative uropathogens: a phase 2, randomised, double-blind, non-inferiority trialSimon Portsmouth, David van Veenhuyzen, Roger Echols, Mitsuaki Machida, Juan Camilo Arjona Ferreira, Mari Ariyasu, Peter Tenke, Tsutae Den Nagata Intravenous infusion of cefiderocol (2 g) three times daily was non-inferior compared with imipenem-cilastatin (1 g each) for the treatment of complicated urinary tract infection in people with multidrug-resistant Gram-negative infections. The results of this study will provide the basis for submission of a New Drug Application to the US Food and Drug Administration. Clinical trials of hospital-acquired pneumonia and carbapenem-resistant infections are ongoing. 2 [Review] Epidemiology of common resistant bacterial pathogens in the countries of the Arab LeagueRima A Moghnieh, Zeina A Kanafani, Hussam Z Tabaja, Sima L Sharara, Lyn S Awad, Souha S Kanj No uniformly organised collection of data regarding antimicrobial resistance has occurred in the countries of the Arab League. 19 countries of the Arab League have published data for antimicrobial susceptibility for the WHO priority organisms, and seven of 14 of these organisms are included in this Review (Escherichia coli, Klebsiella spp, Pseudomonas aeruginosa, Acinetobacter baumannii, Salmonella spp, Staphylococcus aureus, and Streptococcus pneumoniae). Although E coli and Klebsiella spp resistance to third-generation cephalosporins is common in all countries, with prevalence reaching more than 50% in Egypt and Syria, carbapenem resistance is emerging, albeit with a prevalence of less than 10%. 3 [Series] Vaccination of haemopoietic stem cell transplant recipients: guidelines of the 2017 European Conference on Infections in Leukaemia (ECIL 7)Catherine Cordonnier, Sigrun Einarsdottir, Simone Cesaro, Roberta Di Blasi, Malgorzata Mikulska, Christina Rieger, Hugues de Lavallade, Giuseppe Gallo, Thomas Lehrnbecher, Dan Engelhard, Per Ljungman, European Conference on Infections in Leukaemia group Infection is a main concern after haemopoietic stem cell transplantation (HSCT) and a major cause of transplant-related mortality. Some of these infections are preventable by vaccination. Most HSCT recipients lose their immunity to various pathogens as soon as the first months after transplant, irrespective of the pre-transplant donor or recipient vaccinations. Vaccination with inactivated vaccines is safe after transplantation and is an effective way to reinstate protection from various pathogens (eg, influenza virus and Streptococcus pneumoniae), especially for pathogens whose risk of infection is increased by the transplant procedure. 4 [Series] Ventilatory support after extubation in critically ill patientsSalvatore Maurizio Maggiore, Mariangela Battilana, Luca Serano, Flavia Petrini The periextubation period represents a crucial moment in the management of critically ill patients. Extubation failure, defined as the need for reintubation within 2–7 days after a planned extubation, is associated with prolonged mechanical ventilation, increased incidence of ventilator-associated pneumonia, longer intensive care unit and hospital stays, and increased mortality. Conventional oxygen therapy is commonly used after extubation. Additional methods of non-invasive respiratory support, such as non-invasive ventilation and high-flow nasal therapy, can be used to avoid reintubation. 5 Pneumocystis jirovecii pneumonia (PCP) PCR-negative conversion predicts prognosis of HIV-negative patients with PCP and acute respiratory failureJi Soo Choi, Sang Hoon Lee, Ah Young Leem, Joo Han Song, Song Yee Kim, Kyung Soo Chung, Ji Ye Jung, Young Ae Kang, Young Sam Kim, Joon Chang, Moo Suk Park by Ji Soo Choi, Sang Hoon Lee, Ah Young Leem, Joo Han Song, Song Yee Kim, Kyung Soo Chung, Ji Ye Jung, Young Ae Kang, Young Sam Kim, Joon Chang, Moo Suk Park Background Pneumocystis jirovecii pneumonia (PCP) is often fatal in human immunodeficiency (HIV)-negative patients and typically presents with respiratory insufficiency. Predicting treatment failure is challenging. This study aimed to identify prognostic factors and examine PCP polymerase chain reaction (PCR)-negative conversion in non-HIV PCP patients with respiratory failure. Method We retrospectively enrolled 81 non-HIV patients diagnosed with and treated for PCP with respiratory failure in the intensive care unit at a tertiary hospital over a 3-year period. PCP was diagnosed via nested PCR-mediated detection of Pneumocystis jirovecii in induced sputum samples, endotracheal aspirates, and bronchoalveolar lavage fluids. PCP PCR was performed weekly to check for negative conversion. Results The overall survival rate was 35.8%. Seventy-four patients (91.3%) required mechanical ventilation, and 6 (7.4%) required high-flow nasal oxygen treatment. The PCP PCR-negative conversion rate was 70.5% (survivors, 97%; non-survivors, 63.5%); the median time to conversion was 10 (7.0–14.0) days. On univariate analysis, the APACHE II score (p < 0.001), renal failure requiring renal replacement therapy (p = 0.04), PCP PCR-negative conversion (p = 0.003), and the PaO2/FiO2 ratio (first 24 hours) (p < 0.001) significantly correlated with mortality. On multivariate analysis, PCP PCR-negative conversion (hazard ratio, 0.433; 95% confidence interval, 0.203–0.928; p = 0.031) and the PaO2/FiO2 ratio (first 24 hours) (hazard ratio, 0.988; 95% confidence interval, 0.983–0.993; p < 0.001) independently predicted prognosis. Conclusions Determination of PCP PCR-negative conversion and PaO2/FiO2 ratios may help physicians predict treatment failure and mortality in non-HIV PCP patients with respiratory failure. Pneumocystis jirovecii pneumonia (PCP) PCR-negative conversion predicts prognosis of HIV-negative patients with PCP and acute respiratory failure" som kan hentes fra Dansk Selskab for Infektionsmedicin's hjemmeside via linket vist nedenfor:%0D%0A%0D%0Ahttp%3A%2F%2Finfmed.dk%2Fnyheder-udefra%3Frss_filter%3Dpneumoni%26setpoint%3D98622%23100304"> 6 A biomarker approach to syndrome-based treatment of severe childhood illness in malaria-endemic areasAbstract This opinion article deals with the diagnostic clinical challenges faced by clinicians or health care workers in malaria-endemic areas when a severely sick child presents to the clinic with fever, coma or respiratory distress. Indeed, the coexistence of malaria with other severe infections like meningitis, invasive bacterial infection or pneumonia makes appropriate treatment allocation a matter of life and death. The use of biomarkers has been proposed as a potential solution to this problem. The arrival of high-throughput technologies allowed thousands of molecules (transcripts, proteins and metabolites) to be been screened in clinical samples from large cohorts of well/characterised patients. The major aim of these studies was to identify biomarkers that inform important decisions: should this child be referred to hospital? Should antibiotics, anti-malarials, or both, be administered? There is a large discrepancy between the number of biomarker discovery studies published and the number of biomarkers that have been clinically validated, let alone implemented. This article reflects on the many opportunities and obstacles encountered in biomarker research in malaria-endemic areas. 7 A case report of community-acquired Pseudomonas aeruginosa pneumonia complicated with MODS in a previously healthy patient and related literature reviewAbstract Background Pseudomonas aeruginosa is an unusual pathogen in community-acquired pneumonia, especially in previously healthy adults, but often indicates poor prognosis. Case presentation We report a previously healthy patient who developed severe community-acquired pneumonia (CAP) caused by P. aeruginosa. He deteriorated to septic shock and multiple organ dysfunction syndrome (MODS) quickly, complicated by secondary hematogenous central nervous system (CNS) infection. After 1 month of organ support and antipseudomonal therapy, he had significant symptomatic improvement and was discharged from hospital. During treatment, the pathogen developed resistance to carbapenems quickly and the antibiotic regimen was adjusted accordingly. Conclusions According to our case and related literature review, we conclude that more attention should be paid to community-acquired Pseudomonas aeruginosa pneumonia, because of its rapid progression and poor prognosis. 8 A case report of severe recurrent varicella in an ankylosing spondylitis patient treated with adalimumab – a new side effect after 15 years of usageAbstract Background Tumor necrosis factor-α (TNF-α) antagonists, most of which are monoclonal antibodies, became a widespread treatment for autoimmune diseases such as rheumatoid arthritis, ankylosing spondylitis, inflammatory bowel diseases, psoriasis, psoriatic arthritis, hidradenitis suppurativa and uveitis. Their use is based on the blockage of TNF-α, which plays an important role in granulomas formation, development of phagosomes, activation and differentiation of macrophages, immune response against viral pathogens. The multiple adverse effects of TNF-α inhibition have been identified, including a two-to four-fold increased risk of active tuberculosis and other granulomatous conditions and an increased occurrence of some other serious bacterial, fungal and certain viral infections. Case presentation A 34-year-old male patient with disseminated varicella and pneumonitis was admitted to our hospital. The diagnosis of varicella was established serologically by enzyme immunoassay (EIA) and by polymerase chain reaction confirmation of the virus in vesicular fluid. The patient has been receiving adalimumab and methotrexate for the last 3 years due to ankylosing spondylitis and was seropositive to varicella zoster virus prior to the introduction of TNF-α antagonists. Acyclovir was administered for 10 days with the resolution of clinical illness and radiological signs of pneumonitis. Conclusion Due to the use of biological agents, particularly TNF-α inhibitors, as a well-established therapy for some autoimmune diseases, new potential adverse events can be expected in the future and we wanted to point out one of them. To our knowledge this is the first case of recurrent disseminated varicella in a patient taking TNF-α antagonists. 9 A Combination Antibiogram Evaluation for Pseudomonas aeruginosa in Respiratory and Blood Sources from ICU and Non-ICU Settings in US Hospitals [Susceptibility]Puzniak, L., DePestel, D. D., Srinivasan, A., Ye, G., Murray, J., Merchant, S., DeRyke, C. A., Gupta, V. Background: Pseudomonas aeruginosa (PsA) is an important pathogen associated with significant morbidity and mortality. US guidelines for hospital-acquired and ventilator-associated pneumonia recommend the use of two antipseudomonal drugs for high-risk patients to ensure ≥95% of patients receive active empiric therapy. We evaluated the utility of combination antibiograms in identifying optimal PsA drug regimens.Methods: We conducted a retrospective cross-sectional analysis of antimicrobial susceptibility of all non-duplicate PsA blood and respiratory isolates collected between October 1, 2016 and September 30, 2017 from 304 US hospitals in the BD Insights Research Database. Combination antibiograms were used to determine in vitro antimicrobial susceptibility rates for potential PsA combination regimens consisting of a backbone antibiotic (extended-spectrum cephalosporin, carbapenem, or piperacillin/tazobactam) plus an aminoglycoside or fluoroquinolone.Results: Single agent susceptibility rates for the 11,701 non-duplicate PsA isolates ranged from 72.7% for fluoroquinolones to 85.0% for piperacillin/tazobactam. Susceptibility rates were higher for blood versus respiratory isolates (P < 0.05). Antibiotic combinations resulted in increased susceptibility rates, but did not achieve the goal of 95% antibiotic coverage. Adding an aminoglycoside resulted in higher susceptibility rates than adding a fluoroquinolone; piperacillin/tazobactam plus an aminoglycoside had the highest susceptibility rate (93.3%). Intensive care unit (ICU) isolates generally had lower susceptibility rates than non-ICU isolates.Conclusions: Commonly-used antipseudomonal drugs, either alone or in combination, do not achieve 95% coverage against US hospital PsA isolates, suggesting that new drugs are needed to attain this goal. Local institutional use of combination antibiograms has the potential to optimize empiric therapy of difficult-to-treat pathogens. 10 A Comparison of the Mortality Risk Associated With Ventilator-Acquired Bacterial Pneumonia and Nonventilator ICU-Acquired Bacterial PneumoniaIbn Saied, Wafa; Mourvillier, Bruno; Cohen, Yves; Ruckly, Stephane; Reignier, Jean; Marcotte, Guillaume; Siami, Shidasp; Bouadma, Lila; Darmon, Michael; de Montmollin, Etienne; Argaud, Laurent; Kallel, Hatem; Garrouste-Orgeas, Maité; Soufir, Lilia; Schwebel, Carole; Souweine, Bertrand; Glodgran-Toledano, Dany; Papazian, Laurent; Timsit, Jean-François; on behalf of the OUTCOMEREA Study Group Objectives: To investigate the respective impact of ventilator-associated pneumonia and ICU–hospital-acquired pneumonia on the 30-day mortality of ICU patients. Design: Longitudinal prospective studies. Setting: French ICUs. Patients: Patients at risk of ventilator-associated pneumonia and ICU–hospital-acquired pneumonia. Interventions: The first three episodes of ventilator-associated pneumonia or ICU–hospital-acquired pneumonia were handled as time-dependent covariates in Cox models. We adjusted using the case-mix, illness severity, Simplified Acute Physiology Score II score at admission, and procedures and therapeutics used during the first 48 hours before the risk period. Baseline characteristics of patients with regard to the adequacy of antibiotic treatment were analyzed, as well as the Sequential Organ Failure Assessment score variation in the 2 days before the occurrence of ventilator-associated pneumonia or ICU–hospital-acquired pneumonia. Mortality was also analyzed for Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species(ESKAPE) and P. aeruginosa pathogens. Measurements and Main Results: Of 14,212 patients who were admitted to the ICUs and who stayed for more than 48 hours, 7,735 were at risk of ventilator-associated pneumonia and 9,747 were at risk of ICU–hospital-acquired pneumonia. Ventilator-associated pneumonia and ICU–hospital-acquired pneumonia occurred in 1,161 at-risk patients (15%) and 176 at-risk patients (2%), respectively. When adjusted on prognostic variables, ventilator-associated pneumonia (hazard ratio, 1.38 (1.24–1.52); p < 0.0001) and even more ICU–hospital-acquired pneumonia (hazard ratio, 1.82 [1.35–2.45]; p < 0.0001) were associated with increased 30-day mortality. The early antibiotic therapy adequacy was not associated with an improved prognosis, particularly for ICU–hospital-acquired pneumonia. The impact was similar for ventilator-associated pneumonia and ICU–hospital-acquired pneumonia mortality due to P. aeruginosa and the ESKAPE group. Conclusions: In a large cohort of patients, we found that both ICU–hospital-acquired pneumonia and ventilator-associated pneumonia were associated with an 82% and a 38% increase in the risk of 30-day mortality, respectively. This study emphasized the importance of preventing ICU–hospital-acquired pneumonia in nonventilated patients. The members of the OUTCOMEREA Network are listed in the supplementary appendix (Supplemental Digital Content 6, http://links.lww.com/CCM/E185). Supplemental digital content is available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s website (http://journals.lww.com/ccmjournal). The OUTCOMEREA research network entirely funded the study. The authors have disclosed that they do not have any potential conflicts of interest. For information regarding this article, E-mail: timsit@bch.aphp.fr Copyright © by 2018 by the Society of Critical Care Medicine and Wolters Kluwer Health, Inc. All Rights Reserved. 11 A decade of antiretroviral therapy in Uganda: what are the emerging causes of death?Abstract Background The roll out of antiretroviral therapy (ART) in Sub-Saharan Africa led to a decrease in mortality. Few studies have documented the causes of deaths among patients on long term antiretroviral therapy in Sub-Saharan Africa. Our objective was to describe the causes of death among patients on long term ART in Sub-Saharan Africa. Methods We used data from a prospective cohort of ART naïve patients receiving care and treatment at the Infectious Diseases Institute in Kampala, Uganda. Patients were followed up for 10 years. All deaths were recorded and possible causes established using verbal autopsy. Deaths were grouped as HIV-related (ART toxicities, any opportunistic infections (OIs) and HIV-related malignancies) and non-HIV related deaths while some remained unknown. We used Kaplan Meier survival methods to estimate cumulative incidence and rates of mortality for all causes of death. Results Of the 559, (386, 69%) were female, median age 36 years (IQR: 21–44), 89% had WHO clinical stages 3 and 4, and median CD4 count at ART initiation was 98 cells/μL (IQR: 21–163). A total of 127 (22.7%) deaths occurred in 10 years. The HIV related causes of death (n = 70) included the following; Tuberculosis 17 (24.3%), Cryptococcal meningitis 10 (15.7%), Kaposi’s Sarcoma 7(10%), HIV related toxicity 6 (8.6%), HIV related anemia 5(7.1%), Pneumocystis carinii Pneumonia (PCP) 5 (7.1%), HIV related chronic diarrhea 4 (5.7%), Non-Hodgkin Lymphoma 3 (4.3%), Herpes Zoster 2 (2.8%), other 10 (14.3%). The non-HIV related causes of death (n = 20) included non-communicable diseases (diabetes, hypertension, stroke) 6 (30%), malaria 3 (15%), pregnancy-related death 2 (10%), cervical cancer 2 (10%), trauma 1(5%) and others 6 (30%). Conclusion Despite the higher rates of deaths from OIs in the early years of ART initiation, we observed an emergence of non-HIV related causes of morbidity and mortality. It is recommended that HIV programs in resource-limited settings start planning for screening and treatment of non-communicable diseases. 12 A lethal pneumonia model of Acinetobacter baumannii: an investigation in immunocompetent miceXi Zeng, Hao Gu, Yan Cheng, Ke-Ran Jia, Dong Liu, Yue Yuan, Zhi-Fu Chen, Liu-Sheng Peng, Quan-Ming Zou, Yun Shi Acinetobacter baumannii can cause severe nosocomial and community-acquired pneumonia. To study the pathogenesis of A. baumannii and develop new treatments, appropriate mouse models are needed. Most of reported mouse models of pulmonary A. baumannii infection are non-lethal or require mice immunosuppression to enhance infection. These models are not suitable for studying host immune response or evaluating immunotherapies. 13 A Multivariable Prediction Model for Pneumocystis jirovecii Pneumonia in Hematology Patients with Acute Respiratory Failure14 A New Way of Managing Pediatric Pneumonia15 A Novel Role for the Klebsiella pneumoniae Sap (Sensitivity to Antimicrobial Peptides) Transporter in Intestinal Cell Interactions, Innate Immune Responses, Liver Abscess, and VirulenceHsu C, Chang I, Hsieh P, et al. AbstractKlebsiella pneumoniae is an important human pathogen causing hospital-acquired and community-acquired infections. Systemic K. pneumoniae infections may be preceded by gastrointestinal colonization, but the basis of this bacterium’s interaction with the intestinal epithelium remains unclear. Here, we report that the K. pneumoniae Sap (sensitivity to antimicrobial peptides) transporter contributes to bacterial–host cell interactions and in vivo virulence. Gene deletion showed that sapA is required for the adherence of a K. pneumoniae blood isolate to intestinal epithelial, lung epithelial, urinary bladder epithelial, and liver cells. The ΔsapA mutant was deficient for translocation across intestinal epithelial monolayers, macrophage interactions, and induction of proinflammatory cytokines. In a mouse gastrointestinal infection model, ΔsapA yielded significantly decreased bacterial loads in liver, spleen and intestine, reduced liver abscess generation, and decreased mortality. These findings offer new insights into the pathogenic interaction of K. pneumoniae with the host gastrointestinal tract to cause systemic infection. 16 A novel, multiple-antigen pneumococcal vaccine protects against lethal Streptococcus pneumoniae challenge [Microbial Immunity and Vaccines]Chan, W.-Y., Entwisle, C., Ercoli, G., Ramos-Sevillano, E., McIlgorm, A., Cecchini, P., Bailey, C., Lam, O., Whiting, G., Green, N., Goldblatt, D., Wheeler, J. X., Brown, J. S. Current vaccination against Streptococcus pneumoniae uses vaccines based on capsular polysaccharides from selected serotypes, and has led to non-vaccine serotype replacement disease. We have investigated an alternative serotype-independent approach, using multiple-antigen vaccines (MAV) prepared from S. pneumoniae TIGR4 lysates enriched for surface proteins by a chromatography step after culture under conditions that induce expression of heat shock proteins (Hsp, thought to be immune adjuvants). Proteomics and immunoblots demonstrated that compared to standard bacterial lysates, MAV was enriched with Hsps and contained several recognised protective protein antigens, including pneumococcal surface protein A (PspA) and pneumolysin (Ply). Vaccination of rodents with MAV induced robust antibody responses to multiple serotypes, including non-pneumococcal conjugate vaccine serotypes. Homologous and heterologous strains of S. pneumoniae were opsonised after incubation in sera from vaccinated rodents. In mouse models, active vaccination with MAV significantly protected against pneumonia, whilst passive transfer of rabbit serum from MAV vaccinated rabbits significantly protected against sepsis caused by both homologous and heterologous S. pneumoniae strains. Direct comparison of MAV preparations made with or without the heat-shock step showed no clear differences in protein antigen content and antigenicity, suggesting that the chromatography step rather than Hsp induction improved MAV antigenicity. Overall, these data suggest that the MAV approach may provide serotype-independent protection against S. pneumoniae. 17 A retrospective seroepidemiologic survey of Chlamydia pneumoniae infection in patients in Beijing between 2008 and 2017Jingtao Cui, Wenjuan Yan, Hongjie Xie, Shaoxia Xu, Qiaofeng Wang, Weihong Zhang, Anping Ni by Jingtao Cui, Wenjuan Yan, Hongjie Xie, Shaoxia Xu, Qiaofeng Wang, Weihong Zhang, Anping Ni Background Chlamydia pneumoniae (C. pneumoniae) is an obligate intracellular bacterium and a human pathogen that causes respiratory infectious diseases. More than 50% of the adult population worldwide was once infected with C. pneumoniae, but investigations into this topic are insufficient in mainland China. Methods Anti-C. pneumoniae IgG and IgM antibodies were detected using micro-immunofluorescence test in serum samples of patients visiting Peking Union Medical College Hospital between 2008 and 2017 for routine medical purposes, and the aim of this retrospective study was to analyze the test results. Results Among 12,050 serum specimens tested for anti-C. pneumoniae IgG and IgM antibodies, the overall prevalence of anti-C. pneumoniae IgG antibodies was 86.6%, 87.2% for men and 86.0% for women. Adult men (>20 years) were found to have a significantly higher prevalence of anti-C. pneumoniae IgG than women (χ2 = 30.32, P = 0.000). 3 to 5 years old patients were observed to have the lowest prevalence of anti-C. pneumoniae IgG, 42.8%, then increased with age, reaching the highest level of 98.6% in patients over 70 years of age. In the 10,434 specimens with C. pneumoniae IgG antibodies, the total geometric mean titer (GMT) for C. pneumoniae IgG was 45.71. Although GMTs were found to be significantly higher among all men than among all women (t = 5.916, P = 0.000), sex difference actually began in patients over 40 years of age and increased in the elderly. In the total 12,050 specimens, 1.2% had anti-C. pneumoniae IgM, 3.3% had anti-C. pneumoniae IgG with titers equal to or greater than 1:512; 0.39% had ≥4-fold increasing titers of antibodies in acute and convalescent phase paired samples, and 4.4% were finally confirmed to have acute antibodies against C. pneumoniae. 6 to 10 years old patients were found to have the highest rate of both IgM antibodies (3.9%) and acute antibodies (6.2%) against C. pneumoniae. Acute antibodies against C. pneumoniae were found to be more frequent in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD, 14.0%, χ2 = 20.43, P = 0.000), patients with pneumonia (7.8%, χ2 = 51.87, P = 0.000) and patients with acute respiratory tract infection (12.3%, χ2 = 60.91, P = 0.000) than among all patients (4.4%). Both anti-C. pneumoniae IgG and IgM antibodies should be tested for acute antibodies against C. pneumoniae as testing for either alone will underestimate by a maximum of two-thirds the incidence of acute antibodies against C. pneumoniae. Conclusions More than 86% of Chinese patients on an average were once infected with C. pneumoniae. Adult men had both a higher prevalence and higher levels of antibodies than women. 6 to10 year old patients were found to have the most frequent acute infection of C. pneumoniae. C. pneumoniae is associated with AECOPD, pneumonia and acute respiratory tract infection. Anti-C. pneumoniae IgG and IgM should be tested simultaneously to avoid underestimation of acute antibodies against C. pneumoniae. Chlamydia pneumoniae infection in patients in Beijing between 2008 and 2017" som kan hentes fra Dansk Selskab for Infektionsmedicin's hjemmeside via linket vist nedenfor:%0D%0A%0D%0Ahttp%3A%2F%2Finfmed.dk%2Fnyheder-udefra%3Frss_filter%3Dpneumoni%26setpoint%3D98622%23101359"> 18 A systematic review of the association between delayed appropriate therapy and mortality among patients hospitalized with infections due to Klebsiella pneumoniae or Escherichia coli: how long is too long?Abstract Background Temporal relationships between the time to appropriate antibiotic therapy and outcomes are not well described. Methods A systematic literature review and meta-analysis was performed to examine this relationship in patients hospitalized with Klebsiella pneumoniae or Escherichia coli infections. Results Twenty identified studies contained data for patients who received delayed appropriate therapy (DAT) versus appropriate antibiotic therapy for these pathogens. Of the 20 included studies, the majority (19/20) focused on patients with bloodstream infections, and only 1 study evaluated patients with pneumonia. When all DAT results were combined (any delay > 24 h from culture collection or any delay after culture and susceptibility reporting [C& SR]), there was an increased risk of mortality (odds ratio [OR], 1.60 [95% CI, 1.25–2.50]). The risk of mortality was greater when DAT > 48 h from culture collection or DAT > C&SR results were combined (OR, 1.76 [95% CI, 1.27–2.44]). Conclusions Our findings suggest there is a need to shift current treatment practices away from antibiotic escalation strategies that contribute to delayed appropriate therapy and toward early, relatively aggressive and comprehensive, antibiotic therapy, especially among patients with bloodstream infections due to K. pneumoniae or E. coli. 19 Accuracy of comprehensive PCR analysis of nasopharyngeal and oropharyngeal swabs for CT-scan confirmed pneumonia in elderly patients: a prospective cohort study.20 Acinetobacter baumannii OxyR regulates the transcriptional response to hydrogen peroxide [Bacterial Infections]Juttukonda, L. J., Green, E. R., Lonergan, Z. R., Heffern, M. C., Chang, C. J., Skaar, E. P. Acinetobacter baumannii is a Gram-negative opportunistic pathogen that causes diverse infections, including pneumonia, bacteremia, and wound infections. Due to multiple intrinsic and acquired antimicrobial-resistance mechanisms, A. baumannii isolates are commonly multi-drug resistant and infections are notoriously difficult to treat. The World Health Organization recently highlighted carbapenem-resistant A. baumannii as a ‘critical priority’ for the development of new antimicrobials because of the risk to human health posed by this organism. Therefore, it is important to discover mechanisms used by A. baumannii to survive stresses encountered during infection in order to identify new drug targets. In this study, we identified hydrogen peroxide (H2O2) as a stressor produced in the lung during A. baumannii infection using in vivo imaging and defined OxyR as a transcriptional regulator of the H2O2 stress response. Upon exposure to H2O2, A. baumannii differentially transcribes several hundred genes. However, transcriptional upregulation of genes predicted to detoxify hydrogen peroxide is abolished in A. baumannii genetically inactivated for the transcriptional regulator oxyR. Moreover, inactivation of oxyR in both antimicrobial-susceptible and multi-drug-resistant A. baumannii strains impairs growth in the presence of H2O2. OxyR is a direct regulator of katE and ahpF1, which encode the major H2O2-degrading enzymes in A. baumannii, as confirmed through measurement of promoter binding by recombinant OxyR in electromobility shift assays. Finally, an oxyR mutant is less fit than wild-type A. baumannii during infection of the murine lung. This work reveals a mechanism used by this important human pathogen to survive H2O2 stress encountered during infection. 21 Adjunctive Corticosteroids decreased the risk of mortality of non-HIV Pneumocystis Pneumonia22 Agreement between CDC/NHSN surveillance definitions and ECDC criteria in diagnosis of healthcare-associated infections in Serbian trauma patientsOlivera Djuric, Ljiljana Markovic-Denic, Bojan Jovanovic, Vesna Bumbasirevic by Olivera Djuric, Ljiljana Markovic-Denic, Bojan Jovanovic, Vesna Bumbasirevic After three national point prevalence studies (PPS) of healthcare associated infections (HAI) conducted in Serbian acute care hospitals using US (CDC/NHSN) surveillance definitions, Serbia is about to switch to European (ECDC) criteria for the purpose of the fourth HAI PPS. The aim of this study was to compare the US and the European HAI definitions in Serbian trauma intensive care unit (ICU). Prospective surveillance was performed at two surgical-trauma ICUs of the Emergency department of Clinical Center of Serbia. HAIs were prospectively diagnosed by experienced clinician and epidemiologists using both types of HAI definitions simultaneously. The level of agreement between two case definitions was assessed by Cohen’s kappa statistic (k). Of 406 patients, 107 (26.3%) acquired at least one HAI (total of 107 according to US definitions and 141 according to European criteria). For microbiologically confirmed pneumonia agreement was k = 0.99 (95% CI, 0.96–1.00) and for clinically defined k = 0.86 (95% CI, 0.58–1.00). Agreement for bloodstream infections (BSI) was 0.79 (CI 95%, 0.70–0.89). When secondary BSI was excluded from the European classification, (30.9% of all BSI), concordance was k = 1.00 and when microbiologically confirmed catheter related BSI were reported separately as recommended by latest ECDC protocol update, (20.0% of all BSI), concordance was 0.60 (CI 95%, 0.41–0.80). No agreement was found between CLABSI and CRI while slight agreement was found when compared CLABSI and CRI3 (k = 0.11; 95%CI, 0.0–0.22). Agreement for overall UTI was moderate (k = 0.66; 95%CI, 0.53–0.79) while for microbiologically-confirmed symptomatic UTI was perfect (k = 1.00). For CAUTI good agreement was observed (k = 0.77; 95%CI, 0.34–1.0). Microbiological confirmation of PN and UTI should be stimulated and comparison of BSI should be done with emphasis on whether secondary BSI is included. 23 An IncR Plasmid harbored by a hypervirulent, carbapenem resistant Klebsiella pneumoniae strain possesses five tandem repeats of the blaKPC-2::NTEKPC-Id fragment [Mechanisms of Resistance]Dong, N., Liu, L., Zhang, R., Chen, K., Xie, M., Chan, E. W. C., Chen, S. Completed sequences of three plasmids from a carbapenem-resistant, hypervirulent Klebsiella pneumoniae isolate, SH9, were obtained. In addition to the a pLVPK-like virulence-conferring plasmid (pVir-CR-HvKP_SH9), the two MDR plasmids (pKPC-CR-HvKP4_SH9 and pCTX-M-CR-HvKP4_SH9) were predicted to originate from a single pKPC-CR-HvKP4-like multi-replicon plasmid through homologous recombination. Interestingly, blaKPC-2 gene was detectable in five tandem repeats exhibiting the format of a NTEKPC-Id-like transposon (IS26-Tn3-ISKpn8-blaKPC-2-ISKpn6-korC-orf-IS26). The data suggested the important role of DNA recombination on mediating active plasmid evolution. 24 Analysis of acute respiratory infections due to influenza virus A, B and RSV during an influenza epidemic 2018Abstract Purpose We studied the incidence, morbidity and mortality of all patients presenting in our teaching hospital with proven influenza virus and/or respiratory syncytial virus (RSV) infection during the influenza epidemic season 2018 which was characterized by a predominant incidence of influenza virus B type B of the Yamagata line. Methods In the fall of 2017, specific precaution measures in addition to standard measures were implemented, including standardized testing for influenza virus A,B and RSV by multiplex PCR of pharyngeal swabsData from all consecutive patients were analyzed retrospectively. Results Overall 651 patients were examined for the presence of influenza virus and RSV; 214 patients had influenza virus A (n = 36), B (n = 152), and/or RSV (n = 30), including four patients with dual infection. 86% of cases had influenza virus (80% B), and 14% RSV infection. N = 23 cases were treated as outpatients. The rate of acute viral respiratory infections (influenza virus and RSV) was 191 of 2776 (6.9%) admissions to medical wards. Of n = 191 hospitalized cases, n = 44 cases (20.6%) had nosocomial infection. Viral infections were associated with a high morbidity (pneumonia 28.5%, mortality 4.7%). Independent predictors of prolonged hospitalization were the presence of pneumonia, NIV and renal complications, and independent predictors of pneumonia were age ≥ 65 years, bedridden status and CRP ≥ 2.9 mg/dL. Conclusions The rate of nosocomial cases was high despite established precaution measures. RSV was associated with morbidity and mortality comparable to influenza. Pneumonia remains the main complication of acute viral respiratory infections, and antimicrobial treatment should include both antiviral as well as antibacterial agents. 25 Antagonistic effect between tigecycline and meropenem: successful management of KPC-producing Klebsiella pneumoniae infectionAbstract Introduction A woman infected by carbapenem-resistant Klebsiella pneumoniae is reported in this study. Case report Tigecycline and meropenem combination was used, and indeed, in vitro checkerboard synergy test confirmed the antagonism between the two antibiotics. Thus, meropenem was ceased and single high-dose tigecycline was successful against the infection. Subsequent experiments showed that the isolates of the KPC-2-producing K. pneumoniae ST11 clone caused the infection. Conclusion Therefore, tigecycline and meropenem combination should be used with caution. 26 Antibacterial Activity of Lefamulin Against Pathogens Most Commonly Causing Community-Acquired Bacterial Pneumonia: SENTRY Antimicrobial Surveillance Program (2015-2016) [Susceptibility]Paukner, S., Gelone, S. P., Arends, S. J. R., Flamm, R. K., Sader, H. S. Lefamulin, the first semisynthetic pleuromutilin antibacterial for intravenous and oral treatment of community-acquired bacterial pneumonia (CABP), and comparators were evaluated for in vitro activity against a global collection of pathogens commonly causing CABP (n=8595) from the 2015–2016 SENTRY Antimicrobial Surveillance Program. Lefamulin was highly active against pathogens commonly Streptococcus pneumoniae including multidrug resistant and extensively drug resistant strains (MIC50/90 for total and resistant subsets, 0.06/0.12 μg/mL; 100% inhibited at ≤1 μg/mL), Staphylococcus aureus including MRSA (both MIC50/90, 0.06/0.12 μg/mL; 99.8% and 99.6% inhibited at ≤1 μg/mL, respectively), Haemophilus influenzae (MIC50/90, 0.5/1 μg/mL; 93.8% inhibited at ≤1 μg/mL), and Moraxella catarrhalis (MIC50/90, 0.06/0.12 μg/mL; 100% inhibited at ≤0.25 μg/mL), and its activity was unaffected by resistance to other antibacterial classes. 27 Antibodies to protein but not glycolipid structures are important for host defense against Mycoplasma pneumoniae [Host Response and Inflammation]Meyer Sauteur, P. M., de Bruijn, A. C. J. M., Graca, C., Tio-Gillen, A. P., Estevao, S. C., Hoogenboezem, T., Hendriks, R. W., Berger, C., Jacobs, B. C., van Rossum, A. M. C., Huizinga, R., Unger, W. W. J. Antibody responses to Mycoplasma pneumoniae (Mp) correlate with pulmonary Mp clearance. However, Mp-specific IgG antibodies can cross-react with the myelin glycolipid galactocerebroside (GalC) and cause neurologic disorders. We assessed whether anti-glycolipid antibody formation is part of the physiological immune response to Mp. We show that antibodies against Mp-proteins and –glycolipids arise in serum of Mp-infected children and mice. Although antibodies to Mp-glycolipids were mainly IgG, anti-GalC antibodies were only of IgM. B-1a cells, shown to aid in protection against pathogen-derived glycolipids, are lacking in Bruton tyrosine kinase (Btk)-deficient mice. Mp-infected Btk-deficient mice developed Mp-specific IgG responses to Mp-proteins but not to Mp-glycolipids, including GalC. The equal recovery from Mp infection in Btk-deficient as wild-type mice suggests that pulmonary Mp clearance is predominantly mediated by IgG reactive with Mp-proteins and that Mp-glycolipid-specific IgG or IgM is not essential. These data will guide development of Mp-targeting vaccines avoiding induction of neurotoxic antibodies. 28 Antimicrobial activity of ceftaroline and comparator agents tested against organisms isolated from patients with community-acquired bacterial pneumonia in Europe, Asia, and Latin America29 Antimicrobial Activity of Omadacycline Tested against Clinical Bacterial Isolates from Hospitals in China (including Hong Kong) and Taiwan: Results from the SENTRY Antimicrobial Surveillance Program (2013-2016) [Epidemiology and Surveillance]Carvalhaes, C. G., Huband, M. D., Reinhart, H. H., Flamm, R. K., Sader, H. S. Omadacycline is a derivative of minocycline and the first agent of the aminomethylcycline class. A total of 3,282 organisms (one per patient) were consecutively collected from patients hospitalized in China (including Hong Kong) and Taiwan. Susceptibility testing was performed by broth microdilution methods in a central laboratory (JMI Laboratories). The collection included Gram-positive and Gram-negative organisms from patients with pneumonia, bloodstream, skin, community-acquired respiratory, and other infections. Omadacycline was very potent against Staphylococcus aureus (n=689; MIC50/90, 0.12/0.25 mg/L), including methicillin-resistant isolates (MRSA; n=299; MIC50/90, 0.12/0.5 mg/L), and had similar activity across geographic regions. Omadacycline was very active against Streptococcus pneumoniae (highest MIC, 0.25 mg/L), β-hemolytic streptococci (highest MIC, 1 mg/L), viridans group streptococci (highest MIC, 0.25 mg/L), and Enterococcus spp. (highest MIC, 0.5 mg/L) from all geographic regions. Overall, 53.8% of S. pneumoniae were penicillin-resistant (PRSPN; penicillin MIC, ≥2 mg/L) and 10.7% of enterococci (21.2% among E. faecium) were vancomycin-resistant (VRE). Omadacycline was active against Haemophilus influenzae (MIC50/90, 0.5/1 mg/L) regardless of β-lactamase production and was active against Moraxella catarrhalis (MIC50/90, ≤0.12/0.25 mg/L). Against Enterobacteriaceae, omadacycline was most active against Escherichia coli (MIC50/90, 1/2 mg/L), Klebsiella oxytoca (MIC50/90, 1/4 mg/L), and Enterobacter cloacae (MIC50/90, 2/4 mg/L). Omadacycline showed potent in vitro activity against Gram-positive and Gram-negative pathogens isolated from China and Taiwan, and retained activity against problem pathogens, such as MRSA, VRE, PRSPN, and extended-spectrum β-lactamase-producing E. coli. The observed MIC profile in Chinese isolates was very similar to that seen in the US and European surveillance studies. 30 Antimicrobial susceptibilities of specific syndromes created with organ-specific weighted incidence antibiograms (OSWIA) in patients with intra-abdominal infectionsAbstract Background The aim was to evaluate the value of organ-specific weighted incidence antibiogram (OSWIA) percentages for bacterial susceptibilities of Gram-negative bacteria (GNB) collected from intra-abdominal infections (IAIs) during SMART 2010–2014. Methods We retrospectively calculated the OSWIA percentages that would have been adequately covered by 12 common antimicrobials based on the bacterial compositions found in the appendix, peritoneum, colon, liver, gall bladder and pancreas. Results The ESBL positive rates were 65.7% for Escherichia coli, 36.2% for Klebsiella pneumoniae, 42.9% for Proteus mirabilis and 33.1% for Klebsiella oxytoca. Escherichia coli were mainly found in the appendix (76.8%), but less so in the liver (32.4%). Klebsiella pneumoniae constituted 45.2% of the total liver pathogenic bacteria and 15.2–20.8% were found in 4 other organs, except the colon and appendix ( 31 Applying Rapid Whole Genome Sequencing to Predict Phenotypic Antimicrobial Susceptibility Testing Results Among Carbapenem-Resistant Klebsiella pneumoniae Clinical Isolates [Mechanisms of Resistance]Tamma, P. D., Fan, Y., Bergman, Y., Pertea, G., Kazmi, A., Lewis, S., Carroll, K. C., Schatz, M. C., Timp, W., Simner, P. J. Objective: Standard antimicrobial susceptibility testing (AST) approaches lead to delays in the selection of optimal antimicrobial therapy. We sought to determine the accuracy of antimicrobial resistance (AMR) determinants identified by Nanopore whole genome sequencing in predicting AST results.Methods: Using a cohort of 40 clinical isolates (21 carbapenemase-producing carbapenem-resistant Klebsiella pneumoniae, 10 non-carbapenemase-producing carbapenem resistant K. pneumoniae, and 9 carbapenem-susceptible K. pneumoniae), three separate sequencing and analysis pipelines were performed: (1) a real-time Nanopore analysis approach identifying acquired AMR genes, (2) an assembly-based Nanopore approach identifying acquired AMR genes and chromosomal mutations, and (3) an approach using short read correction of Nanopore assemblies. The short read correction of Nanopore assemblies served as the reference standard to determine the accuracy of Nanopore sequencing results.Results: With the real-time analysis approach, full annotation of acquired AMR genes occurred within 8 hours of subcultured isolates. Assemblies sufficient for full resistance gene and single nucleotide polymorphism annotation were available within 14 hours from subcultured isolates. The overall agreement of genotypic results and anticipated AST results for the 40 K. pneumoniae isolates was 77% (range 30-100%) and 92% (range 80-100%) for the real-time approach and the assembly approach, respectively. Evaluating the patients contributing the 40 isolates, the real-time approach and assembly approach could shorten the median time to effective antibiotic therapy by 20 hours and 26 hours, respectively, compared to standard AST.Conclusions: Nanopore sequencing offers a rapid approach to both accurately identify resistance mechanisms as well as predict AST results for K. pneumoniae isolates. Bioinformatics improvements enabling real-time alignment coupled with rapid extraction and library preparation will further enhance the accuracy and workflow of the Nanopore real-time approach. 32 APX001 and Other Gwt1 inhibitor Prodrugs are Effective in Experimental Coccidioides immitis Pneumonia [Experimental Therapeutics]Viriyakosol, S., Kapoor, M., Okamoto, S., Covel, J., Soltow, Q. A., Trzoss, M., Shaw, K. J., Fierer, J. Coccidioidomycosis is a systemic fungal infection caused by the inhalation of the arthroconidia of either of two closely related dimorphic fungi, Coccidioides immitis, and C. posadasii that are endemic in the southwestern US and other areas in the Western Hemisphere. Chronic cavitary pulmonary infections and extra-pulmonary sites of infection are very difficult to treat and often require life-long azole therapy. APX001A is the first in a new class of broad spectrum antifungal agents which inhibit Gwt1, an enzyme which is required for localization of glycosylphosphatidyl inositol (GPI)-anchored mannoproteins in fungi. APX001A and several analogs were highly active against clinical isolates of Coccidioides, inhibiting hyphal growth at low nanogram/ml concentrations. APX001 is the N-phosphonooxymethyl prodrug of APX001A, currently in clinical trials for the treatment of invasive fungal infections. Mice were treated orally once-daily with 26 mg/kg/day of APX001 and the prodrug analog APX2097, two hours after administration of the pan-cytochrome P450 inhibitor 1-aminobenzotriazole, which was used to enhance drug half-life and exposures to more closely mimic human pharmacokinetics of APX001A. Five days of treatment reduced lung colony counts by nearly 3 logs and prevented dissemination, similar to the efficacy of fluconazole dosed orally at 25 mg/kg twice daily. In a survival experiment, both APX001 and APX2097-treated mice survived significantly longer than control and fluconazole treated mice. APX001 and other members of this new class of antifungal agents may offer great promise as effective therapies for coccidioidomycosis. 33 Aspiration pneumonia and pneumonitis: a spectrum of infectious/noninfectious diseases affecting the lungNeill, Sarah; Dean, Nathan Purpose of review Our purpose is to describe aspiration pneumonia/pneumonitis as a spectrum of infectious/noninfectious diseases affecting the lung. We summarize diagnosis, risk factors, treatment, and strategies for prevention of aspiration. Recent findings Aspiration is present in normal individuals, and disease manifestation depends on the chemical characteristics, frequency, and volume of inoculum. Anaerobes, though present, are no longer the predominant microbes isolated in aspiration pneumonia. Targets for preventing aspiration including improved oral hygiene and positional feeding have had mixed results. Patients diagnosed by clinicians with aspiration pneumonia experience greater morbidity and mortality than patients with community-acquired pneumonia. Summary Aspiration pneumonia and pneumonitis are part of the pneumonia continuum and share similarities in pathophysiology, microbiology, and treatment. Modern microbiology demonstrates that the lung is not sterile, and isolates in aspiration pneumonia frequently include aerobes or mixed cultures. Treatment for aspiration pneumonia should include antibiotic coverage for oral anaerobes, aerobes associated with community-acquired pneumonia, and resistant organisms depending on appropriate clinical context. Additional studies targeting prevention of aspiration and investigating the increased morbidity and mortality associated with aspiration pneumonia are warranted. Correspondence to Sarah Neill, MD, MPH, University of Utah, Division of Pulmonary and Critical Care Medicine, 26N. 1900 E, 701 Wintrobe, Salt Lake City, UT 84132, USA. Tel: +1 512 971 7176; e-mail: Sarah.Neill@hsc.utah.edu Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved. 34 Assessment of factors that influence timely administration of initial antibiotic dose using collaborative process mapping at a referral hospital in Malawi: a case study of pneumonia patientsAbstract Background Timely initiation of antibiotics within one hour of prescription is one of the recommended antibiotic stewardship interventions when managing patients with pneumonia in the emergency department. Effective implementation of this intervention depends on effective communication, a well-established coordination process and availability of resources. Understanding what may influence this aspect of care by using process mapping is an important component when planning for improvement interventions. The aim of the study was to identify factors that influence antibiotic initiation following prescription in the Adult Emergency and Trauma Centre of the largest referral hospital in Malawi. Methods We conducted a prospective observational case study using process mapping of two purposively selected adult pneumonia patients. One of the investigators CM observed the patient from the time of arrival at the triage area to the time he/she received initial dose of antibiotics. With purposively selected members of the clinical team; we used simple questions to analyze the map and identified facilitators, barriers and potential areas for improvement. Results Both patients did not receive the first dose of antibiotic within one hour of prescription. Despite the situation being less than ideal, potential facilitators to timely antibiotic initiation were: prompt assessment and triaging; availability of different expertise, timely first review by the clinician; and blood culture collected prior to antibiotic initiation. Barriers were: long waits, lack of communication/coordinated care and competency gap. Improvements are needed in communication, multidisciplinary teamwork, education and leadership/supervision. Conclusion Process mapping can have a significant impact in unveiling the system-related factors that influence timely initiation of antibiotics. The mapping exercise brought together stakeholders to evaluate and identify the facilitators and barriers. Recommendations here focused on improving communication, multidisciplinary team culture such as teamwork, good leadership and continuing professional development. 35 Association of the Hospital Readmissions Reduction Program With Heart Failure, AMI, and Pneumonia MortalityWadhera RK, Joynt Maddox KE, Wasfy JH, et al. This cohort study examined the effects of the CMS’s Hospital Readmissions Reduction Program, which imposed financial penalties on hospitals with higher-than-expected readmission rates, on mortality among Medicare beneficiaries hospitalized with heart failure, acute myocardial infarction (AMI), or pneumonia. 36 Atypical pathogens in hospitalized patients with community-acquired pneumonia: a worldwide perspectiveAbstract Background Empirical antibiotic coverage for atypical pathogens in community-acquired pneumonia (CAP) has long been debated, mainly because of a lack of epidemiological data. We aimed to assess both testing for atypical pathogens and their prevalence in hospitalized patients with CAP worldwide, especially in relation with disease severity. Methods A secondary analysis of the GLIMP database, an international, multicentre, point-prevalence study of adult patients admitted for CAP in 222 hospitals across 6 continents in 2015, was performed. The study evaluated frequency of testing for atypical pathogens, including L. pneumophila, M. pneumoniae, C. pneumoniae, and their prevalence. Risk factors for testing and prevalence for atypical pathogens were assessed through univariate analysis. Results Among 3702 CAP patients 1250 (33.8%) underwent at least one test for atypical pathogens. Testing varies greatly among countries and its frequency was higher in Europe than elsewhere (46.0% vs. 12.7%, respectively, p 37 Azidothymidine produces synergistic activity in combination with colistin against antibiotic-resistant Enterobacteriaceae [Experimental Therapeutics]Hu, Y., Liu, Y., Coates, A. Bacterial infections remain the leading killer worldwide which is worsened by the continuous emergence of antibiotic resistance. In particular, antibiotic-resistant Enterobacteriaceae is prevalent and extremely difficult to treat. Reusing existing drugs and rejuvenating the therapeutic potential of existing antibiotics represent an attractive novel strategy. Azidothymidine (AZT) is an antiretroviral drug which is used in combination with other antivirals to prevent and to treat HIV/AIDS. AZT is also active against Gram-negative bacteria but has not been developed for that purpose. Here we investigated in vitro and in vivo efficacy of AZT in combination with colistin against antibiotic-resistant Enterobacteriaceae including extended-spectrum beta-lactamase (ESBL), New Delhi metallo-beta-lactamase 1 (NDM) or the mobilized colistin resistance (mcr-1) producing strains. Minimum inhibitory concentration was determined using the broth microdilution method. The combinatory effect of AZT and colistin was examined using the checkerboard method and time-kill analysis. A murine peritoneal infection model was used to test the therapeutic effect of the combination of AZT and colistin. Fractional inhibitory concentration index from checkerboard assay demonstrated that AZT synergized with colistin against 61% and 87% of ESBL-producing Escherichia coli and Klebsiella pneumoniae, respectively, 100% of NDM-1-producing strains and 92% of mcr-1 producing E. coli. Time-kill analysis demonstrated significant synergistic activities when AZT was combined with colistin. In the murine peritoneal infection model, AZT in combination with colistin showed augmented activities of both drugs in the treatment of NDM-1 K. pneumoniae and mcr-1 E. coli infections. AZT and colistin combination poses a potential to be used coherently to treat antibiotic-resistant Enterobacteriaceae infections. 38 Bacterial causes of otitis media with spontaneous perforation of the tympanic membrane in the era of 13 valent pneumococcal conjugate vaccineCorinne Levy, Emmanuelle Varon, Naim Ouldali, Alain Wollner, Franck Thollot, François Corrard, Andreas Werner, Stéphane Béchet, Stéphane Bonacorsi, Robert Cohen by Corinne Levy, Emmanuelle Varon, Naim Ouldali, Alain Wollner, Franck Thollot, François Corrard, Andreas Werner, Stéphane Béchet, Stéphane Bonacorsi, Robert Cohen After pneumococcal conjugate vaccine (PCV) implementation, the number of acute otitis media (AOM) episodes has decreased, but AOM still remains among the most common diagnoses in childhood. From 2% to 17% of cases of AOM feature spontaneous perforation of the tympanic membrane (SPTM). The aim of this study was to describe the bacteriological causes of SPTM 5 to 8 years years after PCV13 implementation, in 2010. From 2015 to 2018, children with SPTM were prospectively enrolled by 41 pediatricians. Middle ear fluid was obtained by sampling spontaneous discharge. Among the 470 children with SPTM (median age 20.8 months), no otopathogen was isolated for 251 (53.4% [95% CI 48.8%;58.0%]): 47.1% of infants and toddlers, 68.3% older children (p 39 Biofilm production by Haemophilus influenzae and Streptococcus pneumoniae isolated from the nasopharynx of children with acute otitis mediaAbstract Background Biofilm production by Haemophilus influenzae and Streptococcus pneumoniae has been implicated in the pathogenesis of otitis media, mainly in chronic and recurrent cases. We studied the “in vitro” biofilm production by these 2 species isolated alone or together from the nasopharynx of children with acute otitis media. Methods The studied strains were from 3 pneumococcal conjugate vaccine (PCV) periods: pre-PCV7, post-PCV7/pre-PCV13 and post-PCV13. A modified microtiter plate assay with crystal violet stain was used to study the biofilm production of 182 H. influenzae and 191 S. pneumoniae strains. Results Overall, 117/181 (64.6%) H. influenzae and 128/191 (66.8%) S. pneumoniae strains produced biofilm. The proportion of biofilm-producing H. influenzae strains was greater with than without the isolation of S. pneumoniae in the same sample (75.5% vs 52.3%, p = 0.001). Conversely, the proportion of biofilm-producing S. pneumoniae strains was not affected by the presence or not of H. influenzae (66.3% vs 67.4%). S. pneumoniae serotypes 6B, 15B/C, 19A, 35F and 35B were the better biofilm producers (80%). Serotypes 11A, 14, 15A, 19F and 19A were more associated with H. influenzae biofilm-producing strains. Overall, 89/94 (94.6%) of cases with combined isolation showed biofilm production by S. pneumoniae or H. influenzae. Conclusion This study emphasizes the high proportion of biofilm production by H. influenzae and S. pneumoniae strains isolated from the nasopharynx of children with acute otitis media, which reinforces the results of studies suggesting the importance of biofilm in the pathogenesis of acute otitis media. 40 Burden and risk factors of invasive group B Streptococcus disease among neonates in a Chinese maternity hospitalAbstract Background There is a lack of data regarding the prevalence of invasive group B streptococcus (GBS) infection among neonates in China. This study aimed to investigate the incidence and mortality of invasive GBS infection and to identify the risk factors in our hospital. Methods Seventy-four cases admitted between January 2011 and December 2016 was included in this study. A retrospective matched case-control study was conducted in a tertiary maternity and paediatric hospital. Risk factors for the acquisition of invasive GBS infection and mortality were analysed by univariable and multivariable analysis. Results We collected and analysed data from 74 infants aged 41 Burden of Streptococcus pneumoniae sepsis in children after introduction of pneumococcal conjugate vaccines - a prospective population-based cohort studyAsner S, Agyeman P, Gradoux E, et al. AbstractBackgroundPopulation-based studies assessing the impact of pneumococcal conjugate vaccines (PCV) on burden of pneumococcal sepsis in children are lacking. We aimed to assess this burden following introduction of PCV-13 in a nationwide cohort study.MethodsThe Swiss Pediatric Sepsis Study (09/2011–12/2015) prospectively recruited children 42 C-rac-king the Code of Smoke-induced Pneumonia Susceptibility43 Cardiac events after macrolides or fluoroquinolones in patients hospitalized for community-acquired pneumonia: post-hoc analysis of a cluster-randomized trialAbstract Background Guidelines recommend macrolides and fluoroquinolones in patients hospitalized with community-acquired pneumonia (CAP), but their use has been associated with cardiac events. We quantified associations between macrolide and fluoroquinolone use and cardiac events in patients hospitalized with CAP in non-ICU wards. Methods This was a post-hoc analysis of a cluster-randomized trial as a cohort study; including patients with a working diagnosis of CAP admitted to non-ICU wards without a cardiac event on admission. We calculated cause-specific hazard ratio’s (HR’s) for effects of time-dependent macrolide and fluoroquinolone exposure as compared to beta-lactam monotherapy on cardiac events, defined as new or worsening heart failure, arrhythmia, or myocardial ischemia during hospitalization. Results Cardiac events occurred in 146 (6.9%) of 2107 patients, including heart failure (n = 101, 4.8%), arrhythmia (n = 53, 2.5%), and myocardial ischemia (n = 14, 0.7%). These occurred in 11 of 207 (5.3%), 18 of 250 (7.2%), and 31 of 277 (11.2%) patients exposed to azithromycin, clarithromycin, and erythromycin for at least one day, and in 9 of 234 (3.8%), 5 of 194 (2.6%), and 23 of 566 (4.1%) exposed to ciprofloxacin, levofloxacin, and moxifloxacin, respectively. HR’s for erythromycin, compared to beta-lactam monotherapy, on any cardiac event and heart failure were 1.60 (95% CI 1.09;2.36) and 1.89 (95% CI 1.22;2.91), respectively. HR’s for levofloxacin and moxifloxacin, compared to beta-lactam monotherapy, on any cardiac event were 0.40 (95% CI 0.18;0.87)and 0.56 (95% CI 0.36;0.87), respectively. Findings remained consistent after adjustment for confounders and/or in a sensitivity analysis of radiologically confirmed CAP (n = 1604, 76.1%). Conclusions Among patients with CAP hospitalized to non-ICU wards, erythromycin use was associated with a 68% increased risk of hospital-acquired cardiac events, mainly heart failure. Levofloxacin and moxifloxacin were associated with a lower risk of heart failure. Although our study does not fully exclude confounding bias, findings remained largely unchanged in crude, adjusted, and sensitivity analyses. These findings may caution the use of erythromycin as empirical therapy in these patients. Trial registration The original trial was retrospectively registered under ClinicalTrials.gov Identifier NCT01660204 on August 8th, 2012. 44 Cardiovascular risk profile in individuals initiating treatment for overactive bladder – Challenges and learnings for comparative analysis using linked claims and electronic medical record databasesE. Vonesh, K. L. Gooch, V. Khangulov, C. R. Schermer, K. M. Johnston, S. M. Szabo, J. S. Rumsfeld by E. Vonesh, K. L. Gooch, V. Khangulov, C. R. Schermer, K. M. Johnston, S. M. Szabo, J. S. Rumsfeld For managing overactive bladder (OAB), mirabegron, a β3 adrenergic receptor agonist, is typically used as second-line pharmacotherapy after antimuscarinics. Therefore, patients initiating treatment with mirabegron and antimuscarinics may differ, potentially impacting associated clinical outcomes. When using observational data to evaluate real-world safety and effectiveness of OAB treatments, residual bias due to unmeasured confounding and/or confounding by indication are important considerations. Falsification analysis, in which clinically irrelevant endpoints are tested as a reference, can be used to assess residual bias. The objective in this study was to compare baseline cardiovascular risk among OAB patients by treatment, and assess the presence of residual bias via falsification analysis of OAB patients treated with mirabegron or antimuscarinics, to determine whether clinically relevant comparisons across groups would be feasible. Linked electronic health record and claims data (Optum/Humedica) for OAB patients in the United States from 2011–2015 were available, with index defined as first date of OAB treatment during this period. Unadjusted characteristics were compared across groups at index and propensity-matching conducted. Falsification endpoints (hepatitis C, shingles, community-acquired pneumonia) were compared between groups using odds ratios (ORs) and 95% confidence intervals (CI). The study identified 10,311 antimuscarinic- and 408 mirabegron-treated patients. Mirabegron patients were predominantly older males, with more comorbidities. The analytic sample included 1,188 antimuscarinic patients propensity-matched to 396 mirabegron patients; after matching, no significant baseline differences remained. Estimates of falsification ORs were 0.7 (CI:0.3–1.7) for shingles, 1.5 (CI:0.3–8.2) for hepatitis C, 0.8 (CI:0.4–1.8) and 0.9 (CI:0.6–1.4) for pneumonia. While propensity matching successfully balanced observed covariates, wide CIs prevented definitive conclusions regarding residual bias. Accordingly, further observational comparisons by treatment group were not pursued. In real-world analysis, bias-detection methods could not confirm that differences in cardiovascular risk in patients receiving mirabegron versus antimuscarinics were fully adjusted for, precluding clinically relevant comparisons across treatment groups. 45 Case presentation: persistent adenovirus B3 infections associated with bronchiolitis obliterans treated with cidofovir in a child with mosaic tetrasomy 9pAbstract Background Adenoviruses (AdV) are non-enveloped, double-stranded DNA viruses with multiple serotypes, which cause a variety of end-organ disease in both immunocompetent and immunocompromised individuals. Some adenoviruses can become latent in the mucosa-associated lymphoid tissue (e.g. adenoids and tonsils), with the potential to reactivate sporadically, leading to upper or lower respiratory tract infection and disease. Bronchiolitis Obliterans (BO) is a rare chronic lung disorder which usually follows a severe insult to the respiratory tract. In children, it is a complication of severe infections (as post-infectious BO), typically manifesting after a severe respiratory infection, in previously healthy pre-school children. Symptoms and signs of air trapping (hyperinflated chest, expiratory wheeze) with persistent oxygen requirement are characteristic. The presence of the unusual mosaic tetrasomy 9p genotype in this case, despite standard cidofovir therapy for persistent or chronic adenovirus infection, may have impacted on the child’s long-term clinical outcomes. Case presentation We present a case of persistent AdV B3 infection in a 14-month old boy with mosaic tetrasomy 9p, which persisted for 10 weeks, resulting in radiologically-confirmed BO, requiring cidofovir to control the persistent AdV B3 infection and standard therapy with pulsed steroids. We argue that in the presence of the mosaic tetrasomy 9p, earlier antiviral therapy may have decreased the severity of BO, as this mutation is known to be associated with some degree of immune dysregulation. Conclusions Adenovirus infections are common in children and may persist as latent infections, with subsequent reactivations during loss of immune control, related to systemic illness arising from other causes. In chronic, reactivated AdV infection with pneumonia, BO is a recognised complication. However, in this case, with the presence of the mosaic tetrasomy 9p mutation, earlier antiviral therapy may have reduced such longer term complications, due to the immune dysregulatory nature of this mutation. 46 Ceftobiprole Activity against Gram-Positive and -Negative Pathogens Collected from the United States Across a Decade: 2006 and 2016 [Susceptibility]Pfaller, M. A., Flamm, R. K., Mendes, R. E., Streit, J. M., Smart, J. I., Hamed, K. A., Duncan, L. R., Sader, H. S. Ceftobiprole is an advanced cephalosporin with potent activity against Gram-positive and Gram-negative bacteria that is approved in many European and non-European countries to treat community- and hospital-acquired pneumonia (excluding ventilator-associated pneumonia). This study reports on the activity of ceftobiprole against a large set of clinical isolates from hospitalized patients in the United States in 2016 that caused serious infections including pneumonia, bacteremia, and skin and skin structure infections. To assess any potential temporal changes in ceftobiprole activity, the 2016 results were compared to corresponding MIC data from a 2006 U.S. survey that included key target pathogens. Ceftobiprole exhibited potent activity against Staphylococcus aureus (including methicillin-resistant S. aureus isolates that were 99.3% susceptible), coagulase-negative staphylococci (100% susceptible), Enterococcus faecalis (100% susceptible), Streptococcus pneumoniae (99.7% susceptible), and other tested streptococci. Similarly, ceftobiprole was highly active against Enterobacteriaceae isolates that did not exhibit an ESBL phenotype, including Escherichia coli (99.8% susceptible) and Klebsiella pneumoniae (99.6% susceptible). Against Haemophilus influenzae and Moraxella catarrhalis, 99.6% of all isolates were inhibited at ≤1 mg/L of ceftobiprole, and 72.7% of the Pseudomonas aeruginosa isolates were susceptible to ceftobiprole. With the exception of decreased cephalosporin susceptibility among the Enterobacteriaceae, which correlates with an increased prevalence of ESBL-producing isolates, ceftobiprole had similar activity against the isolate sets collected in 2006 and 2016. Therefore, ceftobiprole remains highly active when tested in vitro against a large number of current Gram-positive and Gram-negative pathogens that cause serious infections. 47 Changes in the incidence and bacterial aetiology of paediatric parapneumonic pleural effusions/empyema in Germany, 2010-2017: a nationwide surveillance studyJohannes G. Liese, Christoph Schoen, Mark van der Linden, Lisa Lehmann, David Goettler, Sabrina Keller, Anna Maier, Florian Segerer, Markus A. Rose, Andrea Streng Parapneumonic pleural effusions/empyema (PPE/PE) are severe complications of community- acquired pneumonia. We investigated the bacterial aetiology and incidence of paediatric PPE/PE in Germany after the introduction of universal pneumococcal conjugate vaccine (PCV) immunisation for infants. 48 Changes in the serotype distribution of Streptococcus pneumoniae causing otitis media after PCV13 introduction in SpainMaría Morales, Guillermo Ludwig, Maria Ercibengoa, Cristina Esteva, Viviana Sanchez-Encinales, Marta Alonso, Carmen Muñoz-Almagro, José Maria Marimón by María Morales, Guillermo Ludwig, Maria Ercibengoa, Cristina Esteva, Viviana Sanchez-Encinales, Marta Alonso, Carmen Muñoz-Almagro, José Maria Marimón One of the beneficial effects of pneumococcal conjugate vaccines (PCVs) has been a decrease in the incidence of non-invasive infections, such as otitis media (OM) caused by vaccine serotypes. In this study, we analyzed the epidemiology of pneumococcal OM before and after PCV13 introduction in 2010. Between 2008 and 2016, the middle ear exudates from 2653 children under 14 years of age with OM were studied in two Spanish provinces (Gipuzkoa and Barcelona), and S. pneumoniae was isolated in 235 (8.9%) of cases. The 204 available isolates were serotyped and distributed in three 3-year periods: one before and two after PCV13 introduction (early and late post-PCV13). A significant decrease in the rate of OM caused by S. pneumoniae was observed mainly due to a decrease in infections caused by all PCV13 serotypes, although exceptions were observed including the persistence of serotype 3 in Gipuzkoa and a weak re-emergence of serotype 19F in both regions. The rate and diversity of non-PCV13 serotypes increased in both regions and an emerging clone causing OM was detected in each region: serotype 23B ST2372 in Gipuzkoa and serotype 11A ST838/ST6521 in Barcelona. The introduction of PCV13 has been followed by a change in the epidemiology of pneumococcal OM, with a decrease in the rate of vaccine serotypes accompanied by an increase in the diversity of non-vaccine serotype and the clonal spreading of different single clones in each region. Streptococcus pneumoniae causing otitis media after PCV13 introduction in Spain" som kan hentes fra Dansk Selskab for Infektionsmedicin's hjemmeside via linket vist nedenfor:%0D%0A%0D%0Ahttp%3A%2F%2Finfmed.dk%2Fnyheder-udefra%3Frss_filter%3Dpneumoni%26setpoint%3D98622%23104356"> 49 Characterization of host responses during Pseudomonas aeruginosa acute lung infection in the lungs and blood and after treatment with the synthetic immunomodulatory peptide IDR-1002 [Host Response and Inflammation]Wuerth, K., Lee, A. H. Y., Falsafi, R., Gill, E. E., Hancock, R. E. W. Pseudomonas aeruginosa is an opportunistic pathogen that causes nosocomial pneumonia and infects patients with cystic fibrosis. P. aeruginosa lung infections are difficult to treat due to bacterial resistance to antibiotics, and strains with multi-drug resistance are becoming more prevalent. Here we examined the use of a small host defense peptide, innate defense regulator 1002 (IDR-1002), in an acute P. aeruginosa lung infection in vivo. IDR-1002 significantly reduced the bacterial burden in the bronchoalveolar lavage fluid (BALF) as well as MCP-1 in the BALF and serum, KC in the serum, and IL-6 in the BALF. RNA-Seq was conducted on lungs and whole blood and the effects of P. aeruginosa, IDR-1002, or the combination of P. aeruginosa and IDR-1002 were evaluated. Differential gene expression analysis showed that P. aeruginosa increased multiple inflammatory and innate immune pathways as well as affected hemostasis, matrix metalloproteinases, collagen biosynthesis, and various metabolism pathways in the lungs and/or blood. Infected mice treated with IDR-1002 had significant changes in gene expression compared to untreated infected mice, with fewer differentially expressed genes associated with the inflammatory and innate immune responses to microbial infection, and treatment also affected morphogenesis, certain metabolic pathways, and lymphocyte activation. Overall, these results show that IDR-1002 was effective in treating P. aeruginosa acute lung infections and associated inflammation. 50 CitAB two-component system-regulated citrate utilization contributes to Vibrio cholerae competitiveness with the gut microbiota [Molecular Pathogenesis]Liu, M., Hao, G., Li, Z., Zhou, Y., Garcia- Sillas, R., Li, J., Wang, H., Kan, B., Zhu, J. Citrate is a ubiquitous compound and can be utilized by many bacterial species, including enteric pathogens, as a carbon and energy source. Genes involved in citrate utilization have been extensively studied in some enteric bacteria, such as Klebsiella pneumoniae, however their role in pathogenesis is still not clear. In this study, we investigated citrate utilization and regulation in Vibrio cholerae, the causative agent of cholera. The putative anaerobic citrate fermentation genes in V. cholerae, consisting of citCDEFXG, citS-oadGAB, and two-component system (TCS) genes citAB, are highly homologous to those in K. pneumoniae. Deletion analysis shows that these cit genes are essential for V. cholerae growth when citrate is the sole carbon source. The expression of citC and citS operons was dependent on citrate and CitAB, whose transcription was autorepressed and regulated by another TCS regulator ArcA. In addition, citrate fermentation was under the control of catabolite repression. Mouse colonization experiments showed that V. cholerae can utilize citrate in vivo using the citrate fermentation pathway and that V. cholerae likely needs to compete with other members of the gut microbiota to access citrate in the gut.
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