Impact of rapid microbial identification on clinical outcomes in bloodstream infection: the RAPIDO randomized trial.

OBJECTIVES: Bloodstream infection has a high mortality rate. It is not clear whether laboratory-based rapid identification of the organisms involved would improve outcome. METHODS: The RAPIDO trial was an open parallel-group multicentre randomized controlled trial. We tested all positive blood cultures from hospitalized adults by conventional methods of microbial identification and those from patients randomized (1:1) to rapid diagnosis in addition to matrix-assisted desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) performed directly on positive blood cultures. The only primary outcome was 28-day mortality. Clinical advice on patient management was provided to members of both groups by infection specialists. RESULTS: First positive blood culture samples from 8628 patients were randomized, 4312 into rapid diagnosis and 4136 into conventional diagnosis. After prespecified postrandomization exclusions, 2740 in the rapid diagnosis arm and 2810 in the conventional arm were included in the mortality analysis. There was no significant difference in 28-day survival (81.5% 2233/2740 rapid vs. 82.3% 2313/2810 conventional; hazard ratio 1.05, 95% confidence interval 0.93-1.19, p 0.42). Microbial identification was quicker in the rapid diagnosis group (median (interquartile range) 38.5 (26.7-50.3) hours after blood sampling vs. 50.3 (47.1-72.9) hours after blood sampling, p < 0.01), but times to effective antimicrobial therapy were no shorter (respectively median (interquartile range) 24 (2-78) hours vs. 13 (2-69) hours). There were no significant differences in 7-day mortality or total antibiotic consumption; times to resolution of fever, discharge from hospital or de-escalation of broad-spectrum therapy or 28-day Clostridioides difficile incidence. CONCLUSIONS: Rapid identification of bloodstream pathogens by MALDI-TOF MS in this trial did not reduce patient mortality despite delivering laboratory data to clinicians sooner.

Risk factors and prognosis of complicated urinary tract infections caused by Pseudomonas aeruginosa in hospitalized patients: a retrospective multicenter cohort study.

PURPOSE: Complicated urinary tract infections (cUTIs) are among the most frequent health-care-associated infections. In patients with cUTI, Pseudomonas aeruginosa deserves special attention, since it can affect patients with serious underlying conditions. Our aim was to gain insight into the risk factors and prognosis of P. aeruginosa cUTIs in a scenario of increasing multidrug resistance (MDR). METHODS: This was a multinational, retrospective, observational study at 20 hospitals in south and southeastern Europe, Turkey, and Israel including consecutive patients with cUTI hospitalized between January 2013 and December 2014. A mixed-effect logistic regression model was performed to assess risk factors for P. aeruginosa and MDR P. aeruginosa cUTI. RESULTS: Of 1,007 episodes of cUTI, 97 (9.6%) were due to P. aeruginosa. Resistance rates of P. aeruginosa were: antipseudomonal cephalosporins 35 of 97 (36.1%), aminoglycosides 30 of 97 (30.9%), piperacillin-tazobactam 21 of 97 (21.6%), fluoroquinolones 43 of 97 (44.3%), and carbapenems 28 of 97 (28.8%). The MDR rate was 28 of 97 (28.8%). Independent risk factors for P. aeruginosa cUTI were male sex (OR 2.61, 95% CI 1.60-4.27), steroid therapy (OR 2.40, 95% CI 1.10-5.27), bedridden functional status (OR 1.79, 95% CI 0.99-3.25), antibiotic treatment within the previous 30 days (OR 2.34, 95% CI 1.38-3.94), indwelling urinary catheter (OR 2.41, 95% CI 1.43-4.08), and procedures that anatomically modified the urinary tract (OR 2.01, 95% CI 1.04-3.87). Independent risk factors for MDR P. aeruginosa cUTI were age (OR 0.96, 95% CI 0.93-0.99) and anatomical urinary tract modification (OR 4.75, 95% CI 1.06-21.26). Readmission was higher in P. aeruginosa cUTI patients than in other etiologies (23 of 97 [23.7%] vs 144 of 910 [15.8%], P=0.04), while 30-day mortality was not significantly different (seven of 97 [7.2%] vs 77 of 910 [8.5%], P=0.6). CONCLUSION: Patients with P. aeruginosa cUTI had characteristically a serious baseline condition and manipulation of the urinary tract, although their mortality was not higher than that of patients with cUTI caused by other etiologies.

The use of dual-energy x-ray absorptiometry in animals.

The use of dual-energy absorptiometry (DXA) to measure bone mineral content (BMC) and bone mineral density (BMD) is widespread in humans and has been adapted to animals because of the need to examine bone and body composition in longitudinal studies. In this review, the indications and techniques for DXA in small-sized animals (rodents, cats, and rabbits) and large-sized animals (dogs, swine, nonhuman primates, sheep, and horses) are discussed. Now that software has been developed for measuring BMD in small laboratory animals, the most frequent use of DXA in animals is in rats. An ultrahigh-resolution mode of acquisition is used for their small bones but also is necessary for other small-sized animals such as rabbits and cats. In larger-sized animals such as dogs, pigs, and sheep, software used in humans has been adapted successfully to measure BMC/BMD and body composition. The human spine and left and right hip protocols are adapted easily to animals of this size, and the software for body composition has been adapted to dogs. Measurement of bone mass around metallic implants is possible in animals and most studies have involved dogs. To ensure precision of DXA in the noninvasive measurement of BMD in animals, attention to positioning and ability of the operator to define the same region of interest using clearly defined anatomical landmarks on the scan image cannot be overemphasized. This is one of the essential requirements for successful densitometry in animals.