156 research outputs found
Multidrug-Resistant Pseudomonas Aeruginosa Bloodstream Infections: Analysis of Trends in Prevalence and Epidemiology
Caspofungin activity against clinical isolates of azole cross-resistant Candida glabrata overexpressing efflux pump genes
Objectives: Several studies have documented the potent in vitro activity of caspofungin against Candida spp. This is of special concern for Candida glabrata infections that are often resistant to many azole antifungal agents and, consequently, difficult to treat. The aim of the present study was to expand the data on the in vitro activity of caspofungin against azole-resistant isolates of C. glabrata. Methods: A total of 50 clinical isolates of C. glabrata were tested for susceptibility to caspofungin. The isolates were cross-resistant to multiple azoles, including fluconazole, itraconazole, ketoconazole and voriconazole. Expression of the resistance-related CgCDR1 and CgCDR2 genes was evaluated by quantitative RT-PCR analysis. The MICs of caspofungin were determined by using the National Committee for Clinical Laboratory Standards M27-A2 reference method. Results: C. glabrata isolates exhibited increased expression of the CDR efflux pump(s), and this was in accordance with their high-level azole resistance. In contrast, all the isolates were highly susceptible to caspofungin (100% of isolates were inhibited at ≤1 mg/L). Conclusions: Our results represent further evidence for the excellent antifungal potency of caspofungin, particularly against C. glabrata isolates expressing cross-resistance to azole
Glycopeptide resistance among coagulase- negative staphylococci that cause bacteremia: epidemiological and clinical findings from a case-control study
A 1-year prospective case-control study (ratio of control patients to case patients, 3:1) was performed to assess
the incidence, risk factors, and genotypic patterns of bacteremia caused by glycopeptide-resistant coagulasenegative
staphylococci (CoNS) and their correlation with hospital glycopeptide use. Among 535 subjects with
CoNS bacteremia, 20 subjects had a glycopeptide-resistant strain (19 strains were resistant to teicoplanin and
1 was resistant to both teicoplanin and vancomycin). The percentage of resistant isolates recovered in 1 year
was 8% in intensive care units and 3% and 2% in medical and surgical wards, respectively. Genotypic analysis
of resistant strains showed different patterns with a high degree of polymorphism. Use of glycopeptides in
individual wards was not statistically associated with the percentage of resistance. Previous exposure to β-lactams
and glycopeptides, multiple hospitalization in the previous year, and concomitant pneumonia were
significantly associated with the onset of glycopeptide-resistant CoNS bacteremia. Mortality rates were 25%
among case patients and 18% among control patients, and they were significantly higher among patients who
presented with concomitant pneumonia and a high Acute Physiology and Chronic Health Evaluation III score
Multicenter evaluation of the RAPIDEC® CARBA NP test for rapid screening of carbapenemase-producing Enterobacteriaceae and Gram-negative nonfermenters from clinical specimens
In vitro Evaluation of BACT/ALERT® VIRTUO®, BACT/ALERT 3D®, and BACTEC™ FX Automated Blood Culture Systems for Detection of Microbial Pathogens Using Simulated Human Blood Samples
Blood culture (BC) is still the standard for diagnosing bloodstream infections (BSIs), especially those caused by bacteria and fungi. Infection-complicating sepsis or septic shock often occurs at BSI onset, making necessary to improve the diagnostic yield of positive BCs. Among the BC systems currently available, the BACT/ALERT® VIRTUO® (VIRTUO) system has been developed to shorten time to detection (TTD) of positive BCs. In this study, we assessed TTD for 330 clinically relevant species including 14 Gram-positive, 14 Gram-negative, and 5 yeast isolates in spiked human blood samples that were tested in parallel with VIRTUO BACT/ALERT® 3D (BTA3D) and BACTEC™ FX (BACTEC) systems. We inoculated 30 colony-forming unit (CFU) from each microbial suspension into BACT/ALERT® Plus or BACTEC™ Plus (aerobic/anaerobic or pediatric) BC bottles, and we used two different blood volumes to simulate, respectively, the BCs collected from adult and pediatric patients. Of 2,610 bottles tested, 2,600 (99.6%) signaled positive in the three systems. Only the BACTEC system did not detect Staphylococcus lugdunensis isolates in anaerobic bottles. Among adult simulated cultures, the median TTD was significantly shorter for aerobic/anaerobic bottles incubated in VIRTUO (11.6 h and 10.1 h) compared to bottles incubated in either BTA3D (13.3 and 12.3 h) or BACTEC (13.5 and 12.2 h) system. Among pediatric simulated cultures, the median TTD was significantly shorter for bottles incubated in VIRTUO (11.2 h) compared to bottles incubated in either the BTA3D (13.0 h) or BACTEC (12.5 h) system. Compared to BTA3D and/or BACTEC systems, VIRTUO allowed faster growth detection for most of the 33 microbial species tested. Notable examples were Salmonella spp. (7.4 h by VIRTUO vs. 10.1 h and 9.2 h by either BTA3D or BACTEC) and Streptococcus agalactiae (8.1 h by VIRTUO vs. 10.3 and 9.4 h by either BTA3D or BACTEC). The few notable exceptions included Stenotrophomonas maltophilia and some Candida species. Together, these findings confirm that VIRTUO has greater potential of improving the laboratory detection of bacteremia and fungemia than the progenitor BTA3D or the competitor BACTEC system
Real life turnaround time of blood cultures in the clinical microbiology laboratory: results of the first Italian survey, May 2015
Background and aims: Blood culture (BC) results are essential to guide antimicrobial chemotherapy for patients with sepsis. However, BC is a time-consuming exam, which can take several days. Reducing BCs turn around time (TAT) could impact on multiple outcome parameters and TAT monitoring is an important tool for measurement of microbiology laboratory performance. The aim of this study was to provide an overview of BC TATs among Italian microbiology laboratories. Materials and methods: Five laboratories collected and recorded, for a month period, date and time of the BC processing events. Cumulative TATs were analysed using the GraphPad software. Results: Participating laboratories reported data from 302 sepsis episodes. The median time from when the BC system produced a positive signal until Gram-stain results were reported was 7.6 hours. A rapid molecular identification and antimicrobial susceptibility testing (AST) was performed in 26.5% of BCs. Mean TAT for identification report was significantly lower when a molecular approach was adopted (12 vs. 28.7 hours, P<0.001). Similarly, results of the molecular AST were obtained more than 24 hours in advance compared with phenotypic AST (mean 13.2 vs. 47.6, P<0.001). TATs from BC positivity of laboratories opened 7 days/week were not significantly lower than those of laboratories opened 6 days/week. Conclusions: BC is a time-consuming exam, however, molecular identification and AST methods can drastically reduce time to results. The lack of difference between TATs observed for laboratories working 7 days/week and 6 days/week, coupled with a high rate of BCs turning positive during the night enable to conclude that the most urgent measure to reduce TATs is the expansion of laboratory regular duty hours
Planar Tc99m – sestamibi scintimammography should be considered cautiously in the axillary evaluation of breast cancer protocols: Results of an international multicenter trial
BACKGROUND: Lymph node status is the most important prognostic indicator in breast cancer in recently diagnosed primary lesion. As a part of an interregional protocol using scintimammography with Tc99m compounds, the value of planar Tc99m sestamibi scanning for axillary lymph node evaluation is presented. Since there is a wide range of reported values, a standardized protocol of planar imaging was performed. METHODS: One hundred and forty-nine female patients were included prospectively from different regions. Their mean age was 55.1 ± 11.9 years. Histological report was obtained from 2.987 excised lymph nodes from 150 axillas. An early planar chest image was obtained at 10 min in all patients and a delayed one in 95 patients, all images performed with 740–925 MBq dose of Tc99m sestamibi. Blind lecture of all axillary regions was interpreted by 2 independent observers considering any well defined focal area of increased uptake as an involved axilla. Diagnostic values, 95% confidence intervals [CI] and also likelihood ratios (LR) were calculated. RESULTS: Node histology demonstrated tumor involvement in 546 out of 2987 lymph nodes. Sestamibi was positive in 30 axillas (25 true-positive) and negative in 120 (only 55 true-negative). The sensitivity corresponded to 27.8% [CI = 18.9–38.2] and specificity to 91.7% [81.6–97.2]. The positive and negative LR were 3.33 and 0.79, respectively. There was no difference between early and delayed images. Sensitivity was higher in patients with palpable lesions. CONCLUSION: This work confirmed that non tomographic Tc99m sestamibi scintimammography had a very low detection rate for axillary lymph node involvement and it should not be applied for clinical assessment of breast cancer
Role of lung ultrasound for the etiological diagnosis of acute lower respiratory tract infection (ALRTI) in children: a prospective study
Objective and design: Our prospective study assesses the role of detailed lung ultrasound (LUS) features to discriminate the etiological diagnosis of acute lower respiratory tract infection (ALRTI) in children. Methodology: We analyzed patients aged from 1 month to 17 years admitted between March 2018 and April 2020 who were hospitalized for ALRTI. For all patients, history, clinical parameters, microbiological data, and lung ultrasound data were collected. Patients were stratified into three main groups ("bacterial", "viral", "atypical") according to the presumed microbial etiology and LUS findings evaluated according to the etiological group. Nasopharyngeal swabs were obtained from all patients. A qualitative diagnostic test developed by Nurex S.r.l. was used for identification of bacterial and fungal DNA in respiratory samples. The Seegene Allplex™ Respiratory assays were used for the molecular diagnosis of viral respiratory pathogens. In addition, bacterial culture of blood and respiratory samples were performed, when indicated. Results: A total of 186 children with suspected ALRTI (44% female) with an average age of 6 were enrolled in the study. We found that some ultrasound findings as size, number and distribution of consolidations, the position and motion of air bronchograms, pleural effusions and distribution of vertical artifacts significantly differ (p < 0.05) in children with bacterial, viral and atypical ALRTI. Conclusion: Our study provides a detailed analysis of LUS features able to predict the ALRTI ethology in children. These findings may help the physicians to better manage a child with ALRTI and to offer personalized approach, from diagnosis to treatment and follow-up
Antimicrobial susceptibility testing of pathogens isolated from blood culture: a performance comparison of Accelerate Pheno (TM) and VITEK (R) 2 systems with the broth microdilution method
Objectives: To compare the performance of the Accelerate Pheno\u2122 system with that of the conventional phenotypic VITEK\uae 2 system for rapid antimicrobial susceptibility testing (AST) of bacterial pathogens from positive blood culture (PBC) samples, based on the reference broth microdilution (BMD) method. Methods: Prospectively collected PBCs that represented patient-unique bloodstream infection episodes were included. For PBC samples showing monomicrobial growth (n\u2009=\u200986), AST was performed using both Accelerate Pheno\u2122 and VITEK\uae 2 systems directly from PBC broth. Colony isolates derived from subculture of PBC broth were then used for BMD testing. AST results were interpreted according to 2017 EUCAST breakpoints. Results: The overall categorical agreement between Accelerate Pheno\u2122 system and BMD was 92.7% (467/504) for Gram-negative organisms and 99.0% (95/96) for Gram-positive organisms, with rates for very major errors of 3.6% (6/166), major errors 2.2% (9/416) and minor errors 3.8% (23/600). The overall categorical agreement between the VITEK\uae 2 system and BMD was 91.7% (463/505) for Gram-negative organisms and 99.0% (97/98) for Gram-positive organisms, with rates of very major errors of 2.4% (4/169), major errors 1.0% (4/416) and minor errors 5.8% (35/603). Importantly, unlike the VITEK\uae 2 system, no false-susceptible results occurred with two colistin-resistant organism-growing PBCs tested using the Accelerate Pheno\u2122 system. Conclusions: Based on these findings, the Accelerate Pheno\u2122 system can be a valid alternative for the rapid AST of Gram-negative and Gram-positive bacteria in bloodstream infections
Lice, rodents, and many hopes: a rare disease in a young refugee
Borrelia recurrentis infection is a louse-borne disease and Leptospirosis is a rat-borne zoonosis, both endemic in areas characterized by a low hygiene condition. This is the first case of life-threatening Borrelia recurrentis and Leptospira species co-infectio
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