We report the first comparative evaluation between the Bruker Biotyper MS (BMS) and the Vitek MS (VMS) for the identification of yeasts. The rate of correct identifications at the species level was comparable using the commercial databases (89.8% versus 84.3%; P ‫؍‬ 0.712), but higher for BMS using an in-house-extended database (100% versus 84.3%; P ‫؍‬ 0.245). Importantly, the rate of misidentification was significantly higher for VMS (1% versus 12.1%; P < 0.0001), including the rate of major errors (0% versus 4.5%; P ‫؍‬ 0.0036). The introduction of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) in the clinical microbiology laboratories is changing the approach to bacterial and fungal identification (1-4). In particular, several studies have already demonstrated the reliability of MALDI-TOF MS in the rapid identification of yeasts in different clinical settings (5-7), evidencing its cost-effectiveness in allowing the initiation of species-targeted antifungal therapy (7-9). To date, four MALDI-TOF MS systems are commercially available: the Microflex LT Biotyper (Bruker Daltonics, Bremen, Germany) (BMS), the Saramis system (bio-Mérieux, Marcy l'Etoile, France), the Vitek MS system (bioMérieux, Marcy l'Etoile, France) (VMS), and, very recently, the Andromas system (Andromas, Paris, France). Several comparative studies have already been performed using the most common systems (BMS and VMS), but, to the best of our knowledge, they have focused only on the identification of bacteria (10-13). Only very recently was a comparative study on yeasts performed using BMS and Saramis (bio-Mérieux, Marcy l'Etoile, France), the previously distributed version of VMS (14). In the present study, we evaluated the ability of BMS and VMS to identify a broad panel of yeasts of medical interest.One hundred ninety-seven isolates from different human samples, previously identified by conventional biochemical techniques or by sequencing the internal transcribed spacer 1 (ITS1) and ITS2 regions, were blindly identified using the two systems. In order to minimize the risk of misidentification related to the use of incomplete and error-filled public databases (15), the sequences obtained were compared to reference data available in two databases: GenBank, searched by using the nucleotide BLAST tool (blast.ncbi.nlm.nih.gov), and the CBS (Centraalbureau voor Schimmelcultures) yeast database (www.cbs.knaw.nl). The panel included 157 (79.7%) isolates belonging to 30 Candida or Candida-related species (Table 1), and 40 (20.3%) isolates belonging to 15 non-Candida species (Table 2). Before processing for MS identification, each isolate was cultured on Sabouraud dextrose (Kima, Padua, Italy) agar and incubated for 24 h at 35°C. For BMS, proteins were extracted as recommended by the manufacturer. Briefly, a loopful of yeasts was suspended in one volume of water and three volumes of absolute ethanol, and after centrifugation, the pellets were processed with an equal amount of formic acid and acetonitrile ...

We evaluated the Verigene Gram-negative blood culture (BC-GN) test, a microarray that detects Gram-negative bacteria and several resistance genes. A total of 102 positive blood cultures were tested, and the BC-GN test correctly identified 97.9% of the isolates within its panel. In cases of sepsis, timely microbiological diagnosis, including data on antimicrobial susceptibility, is crucial for prompt initiation of targeted drug therapy (1). This is not possible with currently used methods, thus causing a significant delay in specific treatment and the empirical use of broad-spectrum antimicrobials (2-4). Nucleic acid-based assays are considered to be a potential adjuvant tool for improving the microbiological diagnosis of sepsis (5-7). These assays may be classified into one of two groups (5-7): (i) those using positive blood cultures, which are potentially useful but burdened by the usual culture-associated drawbacks (i.e., interfering effect of ongoing antibiotics, long time to positivity, and the presence of fastidious pathogens), and (ii) those using blood samples, which are promising but still not developed for the sensitive detection of resistance markers (5-7).In this pilot study, we evaluated the Verigene Gram-negative blood culture (BC-GN) test (Nanosphere, Northbrook, IL, USA), a microarray-based, almost fully automated, and random-access system allowing for bacterial identification (Table 1) and detection of several resistance genes (Table 2) from positive blood cultures. The turnaround time is 2 h, with a hands-on time of Ͻ10 min. The BC-GN test has been approved for clinical use in Europe and is currently under submission for use in the United States.Several papers have already evaluated the Verigene panel dedicated to Gram-positive bacteria (8-12), but this is the first one on the BC-GN test. To investigate its potential clinical usefulness, we evaluated the following parameters: (i) the concordance of identification and of antibiotic susceptibility data with those obtained with the traditional blood culture flowchart, (ii) the time to definitive results, and (iii) the impact of the BC-GN test results on ongoing empirical therapy, evidencing the rate of potential BC-GN-induced antibiotic changes. In this analysis, the following phases of the standard management of blood cultures were considered: time from blood sampling to the loading of bottles into the bioMérieux BacT/Alert system, time to positivity, and time from positivity to Gram stain and subculturing on solid medium (positive bottles are downloaded every 2 h, from 8:00 a.m. to 6:00 p.m. Monday to Friday, 8:00 a.m. to 2:00 p.m. on Saturday, and 9:00 a.m. to 1:00 p.m. on Sunday).Our study prospectively included all blood cultures positive for Gram-negative pathogens submitted to our center from June to September 2013, but only one positive bottle was considered per patient. Antibiotic susceptibility was phenotypically evaluated by disk diffusion from positive blood culture broth (preliminary antibiotic susceptibility testing [pAST]) and by au...

BackgroundInfections and graft-vs-host disease (GvHD) still represent major, not easily predictable complications in allogeneic hematopoietic stem cell transplant (allo-HSCT). Both conditions have been correlated to altered enteric microbiome profiles during the peritransplant period. The main objective of this study was to identify possible early microbiome-based markers useful in pretransplant risk stratification.MethodsStool samples were collected from 96 consecutive patients at the beginning of the pretransplant conditioning regimen (T0) and at 10 (T1) and 30 (T2) days following transplant. When significant in univariate analysis, the identified microbiome markers were used in multivariate regression analyses, together with other significant clinical variables for allo-HSCT-related risk stratification. Four main outcomes were addressed: (1) septic complications, (2) GvHD, (3) relapse of the underlying disease, and (4) mortality.ResultsThe presence of >5% proinflammatory Enterobacteriaceae at T0 was the only significant marker for the risk of microbiologically confirmed sepsis. Moreover, ≤10% Lachnospiraceae at T0 was the only significant factor for increased risk of overall mortality, including death from both infectious and noninfectious causes.Finally, a low bacterial alpha-diversity (Shannon index ≤ 1.3) at T1 was the only variable significantly correlating with an increased risk of GvHD within 30 days.ConclusionsMicrobiome markers can be useful in the very early identification of patients at risk for major transplant-related complications, offering new tools for individualized preemptive or therapeutic strategies to improve allo-HSCT outcomes.

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Aim: Human toxocariasis is caused by infection with the larval stage of nematode parasites of dogs and cats, Toxocara canis or Toxocara cati. These helminths are not able to complete their life cycle in undefinitive hosts and so undergo aberrant migrations in the tissues causing a wide spectrum of signs and symptoms. Eosinophilia is often severe and sometimes represents the only sign of infection, except in ocular and neurological forms. Results: Fever and hepatomegaly were the most common clinical findings. In two cases eosinophilia was not present. Diagnosis was performed by enzyme-linked immunosorbent assay employing excretory-secretory antigens of Toxocara. canis larvae. All patients were successfully treated with oral albendazole with no side effects.Conclusion: Toxocariasis should be considered in differential diagnosis of eosinophilia and in patients with seizures of uncertain origin, isolated hepatomegaly and splenomegaly, bronchospasms or skin rash.