We determined the effect of methicillin resistance on the outcome of patients with Staphylococcus aureus prosthetic joint infections. From January 1995 to December 2004, 33% of 137 episodes of prosthetic joint infections were the result of S. aureus (in monomicrobial or polymicrobial cultures). Thirty-three (24%) episodes among 31 patients were the result of methicillin-susceptible S. aureus and 12 (9%) episodes among 12 patients were the result of methicillin-resistant S. aureus. Overall treatment failure rate was 38%. Patients with methicillin-susceptible S. aureus or methicillin-resistant S. aureus prosthetic joint infections did not differ in age, gender, comorbidities, joint age, prior surgical procedures performed on the affected joint, number of postsurgical medical complications, or duration of intravenous antimicrobial therapy. Patients with methicillin-resistant S. aureus prosthetic joint infection had longer hospital durations (median, 15 versus 10 days). Methicillin-resistant S. aureus in periprosthetic tissue culture resulted in a higher risk of treatment failure (hazard ratio, 9.2; 95% confidence interval, 2.40-35.46) than methicillin-susceptible S. aureus when controlling for joint location (total knee arthroplasty versus total hip arthroplasty [hazard ratio, 5.8; 95% confidence interval, 1.52-22.19]) and removal of hardware (hazard ratio, 0.24; 95% confidence interval, 0.077-0.75). Efforts should be made to prevent methicillin-resistant S. aureus infections of joint arthroplasties and develop new treatment modalities.

Table of contentsP001 - Sepsis impairs the capillary response within hypoxic capillaries and decreases erythrocyte oxygen-dependent ATP effluxR. M. Bateman, M. D. Sharpe, J. E. Jagger, C. G. EllisP002 - Lower serum immunoglobulin G2 level does not predispose to severe flu.J. Solé-Violán, M. López-Rodríguez, E. Herrera-Ramos, J. Ruíz-Hernández, L. Borderías, J. Horcajada, N. González-Quevedo, O. Rajas, M. Briones, F. Rodríguez de Castro, C. Rodríguez GallegoP003 - Brain protective effects of intravenous immunoglobulin through inhibition of complement activation and apoptosis in a rat model of sepsisF. Esen, G. Orhun, P. Ergin Ozcan, E. Senturk, C. Ugur Yilmaz, N. Orhan, N. Arican, M. Kaya, M. Kucukerden, M. Giris, U. Akcan, S. Bilgic Gazioglu, E. TuzunP004 - Adenosine a1 receptor dysfunction is associated with leukopenia: A possible mechanism for sepsis-induced leukopeniaR. Riff, O. Naamani, A. DouvdevaniP005 - Analysis of neutrophil by hyper spectral imaging - A preliminary reportR. Takegawa, H. Yoshida, T. Hirose, N. Yamamoto, H. Hagiya, M. Ojima, Y. Akeda, O. Tasaki, K. Tomono, T. ShimazuP006 - Chemiluminescent intensity assessed by eaa predicts the incidence of postoperative infectious complications following gastrointestinal surgeryS. Ono, T. Kubo, S. Suda, T. Ueno, T. IkedaP007 - Serial change of c1 inhibitor in patients with sepsis – A prospective observational studyT. Hirose, H. Ogura, H. Takahashi, M. Ojima, J. Kang, Y. Nakamura, T. Kojima, T. ShimazuP008 - Comparison of bacteremia and sepsis on sepsis related biomarkersT. Ikeda, S. Suda, Y. Izutani, T. Ueno, S. OnoP009 - The changes of procalcitonin levels in critical patients with abdominal septic shock during blood purificationT. Taniguchi, M. OP010 - Validation of a new sensitive point of care device for rapid measurement of procalcitoninC. Dinter, J. Lotz, B. Eilers, C. Wissmann, R. LottP011 - Infection biomarkers in primary care patients with acute respiratory tract infections – Comparison of procalcitonin and C-reactive proteinM. M. Meili, P. S. SchuetzP012 - Do we need a lower procalcitonin cut off?H. Hawa, M. Sharshir, M. Aburageila, N. SalahuddinP013 - The predictive role of C-reactive protein and procalcitonin biomarkers in central nervous system infections with extensively drug resistant bacteriaV. Chantziara, S. Georgiou, A. Tsimogianni, P. Alexandropoulos, A. Vassi, F. Lagiou, M. Valta, G. Micha, E. Chinou, G. MichaloudisP014 - Changes in endotoxin activity assay and procalcitonin levels after direct hemoperfusion with polymyxin-b immobilized fiberA. Kodaira, T. Ikeda, S. Ono, T. Ueno, S. Suda, Y. Izutani, H. ImaizumiP015 - Diagnostic usefullness of combination biomarkers on ICU admissionM. V. De la Torre-Prados, A. Garcia-De la Torre, A. Enguix-Armada, A. Puerto-Morlan, V. Perez-Valero, A. Garcia-AlcantaraP016 - Platelet function analysis utilising the PFA-100 does not predict infection, bacteraemia, sepsis or outcome in critically ill patientsN. Bolton, J. Dudziak, S. Bonney, A. Tridente, P. NeeP017 - Extracellular histone H3 levels are in...

Background There is a paucity of data on the effect of early de-escalation of antimicrobial therapy on rates of Clostridioides difficile infection (CDI). This retrospective cohort study evaluated impact of de-escalation from antipseudomonal β-lactam (APBL) therapy within 48 hours of Enterobacteriaceae bloodstream infections (BSIs) on 90-day risk of CDI. Methods Adult patients hospitalized for >48 hours for treatment of Enterobacteriaceae BSI at Palmetto Health hospitals in Columbia, South Carolina, from 1 January 2011 through 30 June 2015 were identified. Multivariable Cox proportional hazards regression was used to examine time to CDI in patients who received >48 hours or ≤48 hours of APBL for empirical therapy of Enterobacteriaceae BSI after adjustment for the propensity to receive >48 hours of APBL. Results Among 808 patients with Enterobacteriaceae BSI, 414 and 394 received >48 and ≤48 hours of APBL, respectively. Incidence of CDI was higher in patients who received >48 hours than those who received ≤48 hours of APBL (7.0% vs 1.8%; log-rank P = .002). After adjustment for propensity to receive >48 hours of APBL and other variables in the multivariable model, receipt of >48 hours of APBL (hazard ratio [HR], 3.56 [95% confidence interval {CI}, 1.48–9.92]; P = .004) and end-stage renal disease (HR, 4.27 [95% CI, 1.89–9.11]; P = .001) were independently associated with higher risk of CDI. Conclusions The empirical use of APBL for >48 hours was an independent risk factor for CDI. Early de-escalation of APBL using clinical risk assessment tools or rapid diagnostic testing may reduce the incidence of CDI in hospitalized adults with Enterobacteriaceae BSIs.

Objective: This single-center, retrospective, observational cohort study evaluates the appropriateness of the BioFire® FilmArray® Gastrointestinal (GI) multiplex PCR panel testing at a community-teaching hospital. Methods: All adult, hospitalized patients at Prisma Health Richland Hospital with a documented GI multiplex PCR panel from 1 April 2015 through 28 February 2018 were included in the analysis. Inappropriate use of the GI panel was defined as a test obtained without documented diarrhea, greater than 2 days of hospitalization, redundant use with other diagnostic tests (e.g. Clostridioides difficile PCR), or laxative use in the preceding 48 h. Antibiotic use and host variables were compared between groups with positive and negative results. Results: During the study period, 442 GI panels were obtained, among which 268 (61%) were deemed inappropriate. Primary reasons for inappropriate testing were lack of documented diarrhea ( n = 92), greater than 2 days of hospitalization ( n = 116), having a duplicate C. difficile PCR test ordered ( n = 118), or laxative use in the 48 h before testing ( n = 36). A total of 141 (32%) GI panels were positive. The most frequently identified pathogens were C. difficile (51.1%, n = 72), Enteropathogenic Escherichia coli (17.7%, n = 25), and Norovirus GI/GII (12.1%, n = 17). Patients with negative GI panel results were initiated on antibiotics significantly less frequently than those with positive GI panels (62.5% versus 80.2%, p < 0.00001). Conclusion: Stewardship opportunities exist to optimize the diagnostic application of the GI multiplex PCR panel.