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While echinocandins remain the preferred antifungal therapy for candidemia, bloodstream infections caused by C. auris, C. glabrata, or, at a lesser extent, C. parapsilosis may be difficult to treat with these antifungal agents. This is in view of the high propensity of the above-mentioned species to develop antifungal resistance or tolerance during treatment.Candida auris and other Candida species (C. albicans, C. glabrata, C. parapsilosis, C. tropicalis, and C. krusei) are important causes of bloodstream infection. Early or prolonged treatment with antifungal agents is often required. The inhibitory effect of antifungal agents in the patients' bloodstream may compromise the sensitivity of blood culture (BC) to diagnose and/or monitor patients with candidemia. Using a clinical BC simulation model, we compared antimicrobial drug-neutralizing BC media in BacT/Alert FA PLUS (FAP) or Bactec Plus Aerobic/F (PAF) bottles with non-neutralizing BC media in Bactec Mycosis IC/F (MICF) bottles to allow Candida growth in the presence of 100%, 50%, or 25% peak serum level (PSL) antifungal concentrations. In total, 117 organism/antifungal combinations were studied, and Candida growth was detected after incubating bottles into BacT/Alert VIRTUO or Bactec FX BC systems. Compared to control (without antifungal) bottles, both FAP and PAF bottles with 100% PSL antifungal concentrations allowed 100% recovery for C. auris, C. glabrata, and C. parapsilosis, whereas recovery was below 100% for C. albicans, C. krusei, and C. tropicalis. MICF bottles were less efficient at 100%, 50%, or 25% PSL antifungal concentrations, for all Candida species, except for C. auris. While azoles and amphotericin B did not hinder Candida growth in FAP or PAF bottles, echinocandins allowed C. auris, C. glabrata, and C. parapsilosis to grow in FAP, PAF, or MICF bottles. Overall, the maximum time to detection was 4.6 days. Taken together, our findings emphasize the reliability of BCs in patients undergoing anti

Direct use of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) on positive blood culture (PBC) bottles may accelerate the identification of bloodstream infection (BSI) causing organisms (1), particularly anaerobic bacteria for which BSI-associated mortality rates are high (2)..

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 BACTECTM FX (BACTEC) systems. We inoculated 30 colony-forming unit (CFU) from each microbial suspension into BACT/ALERT® Plus or BACTECTM 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.

The bacteremia level as well as the administration of antibiotics before blood collection may significantly affect the recovery of bacterial pathogens from pediatric blood cultures in BacT/Alert Virtuo or Bactec FX BC systems, which remain the common techniques to diagnose bacteremia in pediatric patients. We simulated pediatric blood cultures with low or intermediate bacteremia level to evaluate BacT/Alert PF Plus and Bactec Peds Plus blood culture bottles for resin-based inactivation of 16 antibiotic–bacterium combinations. Overall, 105/192 (54.7%) of BacT/Alert PF Plus bottles and 69/192 (36.0%) of Bactec Peds Plus bottles allowed organisms to grow when exposed to antibiotics. In particular, both BacT/Alert PF Plus and Bactec Peds Plus bottles proved to be effective with piperacillin/tazobactam and Pseudomonas aeruginosa or with oxacillin and methicillin-susceptible Staphylococcus aureus (100% growth), whereas no effectiveness was apparent with ceftriaxone and Escherichia coli, Streptococcus agalactiae, or Streptococcus pneumoniae or with cefepime and E. coli (0% growth). In some relevant instances (e.g., with vancomycin and methicillin-resistant S. aureus or Streptococcus pneumoniae), BacT/Alert PF Plus bottles were superior to Bactec Peds Plus bottles. Together, these findings underscore the potentiality of resin-containing bottles to enhance diagnosis of bacteremia in pediatric patients on antimicrobial therapy. This is particularly true with one of the evaluated BC systems and with simulated intermediate bacteremia level only.

This study evaluated and compared the accuracy of BCID2 with that of BCID to identify bacterial species and relative antimicrobial resistance genes directly from positive BCs. We used archived samples from positive BCs (1.5 ml thereof mixed with 100 ml of dimethyl sulfoxide and stored at 280°C), which had prospectively been processed with the BD Bactec 9240 (BD Diagnostic Systems, Sparks, MD), BacTAlert 3D (bioMérieux), or BacTAlert Virtuo (bioMérieux) system at two hospital microbiology laboratories from January 2018 to August 2020.

Sir, Recently, EUCAST developed a rapid antimicrobial susceptibility testing (RAST) method for direct use on positive blood culture (BC) samples, which relies on EUCAST standard disc diffusion (DD) methodology and allows inhibition zone reading within 4–8 h of BC positivity.We herein report on EUCAST RAST results for BCs consecutively collected between June 2019 and December 2019 that contained E. coli (n = 134)or K. pneumoniae (n = 66) isolates.

We aimed to report a 32-month laboratory experience with the eazyplex® CSF direct panel assay for the rapid diagnosis of meningitis due to six most common bacterial species (Escherichia coli, Haemophilus influenzae, Listeria monocytogenes, Neisseria meningitidis, Streptococcus agalactiae, and Streptococcus pneumoniae). We included all cerebrospinal fluid (CSF) samples from patients admitted with a clinical suspicion of meningitis/encephalitis between May 2016 and December 2018 at our hospital. In addition to the eazyplex® assay, both Gram stain microscopy and culture were performed, and results were confirmed with 16S rRNA PCR/sequencing. Patients’ demographics and relevant clinical information were collected. Of 135 studied patients, 44 (32.6%) had a microbiologically documented diagnosis of meningitis. Overall, we identified 21 S. pneumoniae, 10 N. meningitidis, 6 L. monocytogenes, 3 E. coli, 2 Streptococcus pyogenes, 1 S. agalactiae, and 1 Citrobacter koseri as aetiological agents. The eazyplex® assay allowed identification in 40 (90.9%) cases, with four not identified cases due to microorganisms not included in the panel at the time of testing. Thirty-two (72.7%) cases had positive culture results, whereas 28 (63.6%) cases had positive Gram stain results. Notably, combining Gram stain and eazyplex® assay allowed identification in 100% of cases. After notification of rapid results, physicians modified the empiric antibiotic therapy, which became appropriate in three patients (all with L. monocytogenes meningitis). The eazyplex® CSF panel assay worked better than culture in detecting the most common agents of bacterial meningitis and accelerated the diagnosis leading to timely initiation or continuation of appropriate antibiotic therapy.

Background: Nowadays, the global spread of resistance to oxyimino-cephalosporins in Enterobacteriaceae implies the need for novel diagnostics that can rapidly target resistant organisms from these bacterial species. Methods: In this study, we developed and evaluated a Direct Mass Spectrometry assay for Beta-Lactamase (D-MSBL) that allows direct identification of (oxyimino)cephalosporin-resistant Escherichia coli or Klebsiella pneumoniae from positive blood cultures (BCs), by using the matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) technology. Results: The D-MSBL assay was performed on 93 E. coli or K. pneumoniae growing BC samples that were shortly co-incubated with cefotaxime (CTX) as the indicator cephalosporin. Susceptibility and resistance defining peaks from the samples’ mass spectra were analyzed by a novel algorithm for bacterial organism classification. The D-MSBL assay allowed discrimination between E. coli and K. pneumoniae that were resistant or susceptible to CTX with a sensitivity of 86.8% and a specificity of 98.2%. Conclusion: The proposed algorithm-based D-MSBL assay, if integrated in the routine laboratory diagnostic workflow, may be useful to enhance the establishment of appropriate antibiotic therapy and to control the threat of oxyimino-cephalosporin resistance in hospital.

We tested 59 common and 27 uncommon Aspergillus species isolates for the susceptibility to the mold-active azole antifungal agents, itraconazole, voriconazole, and posaconazole, using the Sensititre method. The overall essential agreement with the CLSI reference method was 96.5% for itraconazole and posaconazole, and 100% for voriconazole. By Sensititre, as well as CLSI, all of 10 A. fumigatus isolates with a cyp51 mutant genotype were classified as being non-wild-type (MIC > ECV) to triazoles.

INTRODUCTION: Culture is regarded as the gold standard for the detection of genital mycoplasma in clinical samples. Commercially available diagnostic kits, based on liquid broth cultures, provide interesting alternatives to conventional culture. We assessed the laboratory performances of Mycoplasma IES (IES), the Mycofast Revolution (REV) and Mycoplasma IST 2 (IST2) compared to A7 agar plates for the detection of Ureaplasma urealyticum and Mycoplasma hominis in clinical samples. METHODOLOGY: From April to July 2013, endocervical or vaginal samples were collected from sexually active women with abnormal vaginal discharge. Each specimen was tested in parallel using the three commercial kits and the A7 agar plates. RESULTS: A total of 303 samples were included in this study, 35.6% (108/303) of which were positive on A7 plates. Sensitivities for the detection of U. urealyticum of IES, REV and IST2 were 100%, 96.2% and 95.3%, respectively while those for M. hominis were of 92.8%, 92.8% and 85.7%, respectively. Specificity was 100% for the 3 methods. Concerning antimicrobial susceptibility testing, full agreement between IES and REV was documented. CONCLUSIONS: The Mycoplasma IES kit was found to be equivalent or superior compared to other commercial culture-based assays for a rapid and accurate identification of U. urealyticum and M. hominis and detection of resistance. It might be considered a cost-effective tool for detection of these organisms, particularly attractive in developing countries.

The authors report on the first case of the intraventricular administration of tigecycline described in the Western literature. A 22-year-old man developed cerebrospinal fluid infection from an extremely drug-resistant strain of Acinetobacter baumannii as a complication of endoscopic transsphenoidal surgery for the removal of a giant pituitary adenoma. The patient was safely and successfully treated with the prolonged intraventricular administration of tigecycline. Here, the authors provide the schedule details that can be invaluable in treating meningitis from extremely drug-resistant bacterial strains. Intraventricular tigecycline can be a valuable tool against multidrug-resistant central nervous system infections.

We directly tested 484 organisms from clinical (n = 310) and simulated (n = 174) positive blood cultures using the NG-Test Carba 5 assay for carbapenemase-producing Enterobacterales detection. The assay identified all but 4 of the KPC (170/171), OXA-48-like (22/22), VIM (19/21), and NDM (14/15) producers with no false positives. Among the clinical Klebsiella pneumoniae organisms tested, 122 of 123 KPC, 1 of 1 OXA-48-like, and 1 of 2 VIM producers were detected by the assay. Some VIM and NDM producers yielded scant but still-readable bands with the assay. No organisms produced the IMPS that the assay was designed to detect.

Despite the current reliance on blood cultures (BCs), the diagnosis of bloodstream infections (BSIs) can be sped up using new technologies directly on positive BC bottles. Two methods (the MALDI BioTyper system and FilmArray BCID panel) are potentially applicable. In this study, we performed a large-scale clinical evaluation (1,585 microorganisms from 1,394 BSI episodes) on the combined use of MALDI BioTyper and FilmArray BCID compared to a reference (culture-based) method. As a result, 97.7% (1,362/1,394) of the BSIs were correctly identified by our MALDI BioTyper and FilmArray BCID-based algorithm. Specifically, 65 (5.3%) out of 1,223 monomicrobial BCs that provided incorrect or invalid identifications with the MALDI BioTyper were accurately detected by the FilmArray BCID; additionally, 153 (89.5%) out of 171 polymicrobial BCs achieved complete identification with the FilmArray BCID. Conversely, full use of the MALDI BioTyper would have resulted in the identification of only 1 causative organism in 97/171 (56.7%) of the polymicrobial cultures. By applying our diagnostic algorithm, the median time to identification was shortened (19.5 hours versus 41.7 hours with the reference method; P <0.001), and the minimized use of the FilmArray BCID led to significant cost savings. Twenty-six out of 31 microorganisms that could not be identified were species/genera not designed to be detected with the FilmArray BCID, indicating that subculture was not dispensable for a few of our BSI episodes. In summary, a fast and effective testing of BC bottles is realistically adoptable in the clinical microbiology laboratory workflow, although the usefulness of this testing for the management of BSIs remains to be established.

Sensititre YeastOne (SYO) is an affordable alternative to the Clinical and Laboratory Standards Institute (CLSI) reference method for antifungal susceptibility testing. In this study, the MICs of yeast isolates from 1,214 bloodstream infection episodes, generated by SYO during hospital laboratory activity (January 2005 to December 2013), were reanalyzed using current CLSI clinical breakpoints/epidemiological cutoff values to assign susceptibility (or the wild-type [WT] phenotype) to systemic antifungal agents. Excluding Candida albicans (57.4% of all isolates [n = 1,250]), the most predominant species were Candida parapsilosis complex (20.9%), Candida tropicalis (8.2%), Candida glabrata (6.4%), Candida guilliermondii (1.6%), and Candida krusei (1.3%). Among the non-Candida species (1.9%), 7 were Cryptococcus neoformans and 17 were other species, mainly Rhodotorula species. Over 97% of Candida isolates were susceptible (WT phenotype) to amphotericin B and flucytosine. Rates of susceptibility (WT phenotype) to fluconazole, itraconazole, and voriconazole were 98.7% in C. albicans, 92.3% in the C. parapsilosis complex, 96.1% in C. tropicalis, 92.5% in C. glabrata, 100% in C. guilliermondii, and 100% (excluding fluconazole) in C. krusei. The fluconazole-resistant isolates consisted of 6 C. parapsilosis complex isolates, 3 C. glabrata isolates, 2 C. albicans isolates, 2 C. tropicalis isolates, and 1 Candida lusitaniae isolate. Of the non-Candida isolates, 2 C. neoformans isolates had the non-WT phenotype for susceptibility to fluconazole, whereas Rhodotorula isolates had elevated azole MICs. Overall, 99.7% to 99.8% of Candida isolates were susceptible (WT phenotype) to echinocandins, but 3 isolates were nonsusceptible (either intermediate or resistant) to caspofungin (C. albicans, C. guilliermondii, and C. krusei), anidulafungin (C. albicans and C. guilliermondii), and micafungin (C. albicans). However, when the intrinsically resistant non-Candida isolates were included

Cupriavidus bacteremia is a rare infection and identification of the pathogen is difficult. We present four cases of bacteremia by Cupriavidus metallidurans that were initially identified to the genus level by both Bruker and Vitek matrix-assisted laser desorption ionization-time of flight mass spectrometry and later identified to the species level by 16S rRNA gene sequencing. To our knowledge, these are the first cases of C. metallidurans catheter-related infections. Patients were successfully treated with antibiotic therapy and catheter removal.

Sensititre YeastOne (SYO) is an affordable alternative to the Clinical and Laboratory Standards Institute (CLSI) reference method for antifungal susceptibility testing. In this study, MICs of yeast isolates from 1,214 bloodstream infection episodes, generated by SYO during hospital laboratory activity (January 2005 to December 2013), were reanalyzed using current CLSI clinical breakpoints/epidemiological cutoff values to assign susceptibility (or wild type [WT]) to systemic antifungal agents. Excluding Candida albicans (57.4% of all isolates [n = 1,250]), the most predominant species were Candida parapsilosis complex (20.9%), Candida tropicalis (8.2%), Candida glabrata (6.4%), Candida guilliermondii (1.6%), and Candida krusei (1.3%). Among non-Candida species (1.9%), 7 were Cryptococcus neoformans and 17 other species, mainly Rhodotorula species. Over 97% of Candida isolates were WT to amphotericin B and flucytosine. Susceptibility/WT rates to fluconazole, itraconazole, and voriconazole were 98.7% in C. albicans, 92.3% in C. parapsilosis complex, 96.1% in C. tropicalis, 92.5% in C. glabrata, 100% in C. guilliermondii, and 100% (excluding fluconazole) in C. krusei. The fluconazole-resistant isolates were 6 C. parapsilosis complex, 3 C. glabrata, 2 C. albicans, 2 C. tropicalis, and 1 Candida lusitaniae. Of non-Candida isolates, 2 C. neoformans were non-WT to fluconazole, whereas Rhodotorula isolates had elevated azole MICs. Overall, 99.7%-99.8% of Candida isolates were susceptible/WT to echinocandins, but 3 isolates were nonsusceptible (either intermediate or resistant) to caspofungin (C. albicans, C. guilliermondii, and C. krusei), anidulafungin (C. albicans and C. guilliermondii), and micafungin (C. albicans). Yet, including the intrinsically resistant non-Candida isolates, the echinocandin nonsusceptibility reached 1.8%. In summary, the SYO method proved to be able to detect yeast species showing antifungal resistance or reduced susceptibility.

We compared the clinical performances of the BacT/Alert Plus (bioMérieux) and Bactec Plus (Becton Dickinson) aerobic and anaerobic blood culture (BC) media with adsorbent polymeric beads. Patients ≥ 16 years old with suspected bloodstream infections (BSIs) were enrolled in intensive care units and infectious disease wards. A single 40-ml blood sample was collected from each and used to inoculate (10 ml/bottle) one set of BacT/Alert Plus cultures and one set of Bactec Plus cultures, each set consisting of one aerobic and one anaerobic bottle. Cultures were incubated ≤ 5 days in the BacT/Alert 3D and Bactec FX instruments, respectively. A total of 128 unique BSI episodes were identified based on the recovery of clinically significant growth in 212 aerobic cultures (106 BacT/Alert and 106 Bactec) and 151 anaerobic cultures (82 BacT/Alert and 69 Bactec). The BacT/Alert aerobic medium had higher recovery rates for Gram-positive cocci (P = 0.024), whereas the Bactec aerobic medium was superior for recovery of Gram-negative bacilli (P = 0.006). BacT/Alert anaerobic medium recovery rates exceeded those of the Bactec anaerobic medium for total organisms (P = 0.003), Gram-positive cocci (P = 0.013), and Escherichia coli (P = 0.030). In terms of capacity for diagnosing the 128 septic episodes, the BacT/Alert and Bactec sets were comparable, although the former sets diagnosed more BSIs caused by Gram-positive cocci (P = 0.008). They also allowed earlier identification of coagulase-negative staphylococcal growth (mean, 2.8 h; P = 0.003) and growth in samples from patients not on antimicrobial therapy that yielded positive results (mean, 1.3 h; P < 0.001). Similarly high percentages of microorganisms in BacT/Alert and Bactec cultures (93.8% and 93.3%, respectively) were identified by direct matrix-assisted laser desorption ionization-time of flight mass spectrometry assay of BC broths. The BacT/Alert Plus media line appears to be a reliable, timesaving tool for routine detection

Spontaneous chylothorax is rare in adults. We present an unusual case that was complicated by 28 Prevotella bivia empyema. Full recovery was achieved with chest-tube drainage and prompt 29 treatment with intravenous clindamycin.

Our aims were to identify (i) risk factors associated with the acquisition of multidrug-resistant (MDR, to 3 or more classes of antimicrobials) Proteus mirabilis isolates responsible for bloodstream infections (BSIs) and (ii) the impact on mortality of such infections. Risk factors for acquiring MDR P. mirabilis BSIs were investigated in a case-case-control study; those associated with mortality were assessed by comparing survivors and nonsurvivors in a cohort study. The population consisted of 99 adult inpatients with P. mirabilis BSIs identified by our laboratory over an 11-year period (1999 to 2009), 36 (33.3%) of which were caused by MDR strains, and the overall 21-day mortality rate was 30.3%. Acquisition of an MDR strain was independently associated with admission from a long-term care facility (odds ratio [OR], 9.78; 95% confidence interval [CI], 1.94 to 49.16), previous therapy with fluoroquinolones (OR, 5.52; 95% CI, 1.30 to 23.43) or oxyimino-cephalosporins (OR, 4.72; 95% CI, 1.31 to 16.99), urinary catheterization (OR, 3.89; 95% CI, 1.50 to 10.09), and previous hospitalization (OR, 2.68; 95% CI, 10.4 to 6.89). Patients with MDR P. mirabilis BSIs received inadequate initial antimicrobial therapy (IIAT, i.e., treatment with drugs to which the isolate displayed in vitro resistance) more frequently than those with non-MDR infections; they also had increased mortality and (for survivors) longer post-BSI-onset hospital stays. In multivariate regression analysis, 21-day mortality was associated with septic shock at BSI onset (OR, 12.97; 95% CI, 32.2 to 52.23), P. mirabilis isolates that were MDR (OR, 6.62; 95% CI, 16.4 to 26.68), and IIAT (OR, 9.85; 95% CI, 26.7 to 36.25), the only modifiable risk factor of the 3. These findings can potentially improve clinicians' ability to identify P. mirabilis BSIs likely to be MDR, thereby reducing the risk of IIAT--a major risk factor for mortality in these cases--and facilitating the prompt implementation of appropriate in

KPC-type carbapenemases are emerging in Klebsiella pneumoniae and other Gram-negative pathogens worldwide. Rapid and sensitive detection of these resistance determinants has become relevant to clinical management and infection control. We evaluated the bioMérieux EasyQ real-time PCR assay for bla(KPC) detection with 300 members of the Enterobacteriaceae, including 29 control strains producing known carbapenemases and 271 nonreplicate clinical isolates. The EasyQ assay correctly detected all of the 111 isolates harboring bla(KPC) genes, with no false positives, and results were available within 2 h.

Although resistance to tigecycline has been reported in surveillance studies, a very few reports described the emergence of resistance in vivo. We report two cases of patients with infections due to SHV-12 producing Klebsiella pneumoniae and K. pneumoniae carbapenemase-3 (KPC-3) producing Escherichia coli, which developed tigecycline resistance in vivo after treatment. The reported limited experience underlines the risk of occurrence of tigecycline MIC increase under treatment pressure.

We evaluated the reliability of the Bruker Daltonik's MALDI Biotyper system in species-level identification of yeasts directly from blood culture bottles. Identification results were concordant with those of the conventional culture-based method for 95.9% of Candida albicans (187/195) and 86.5% of non-albicans Candida species (128/148). Results were available in 30 min (median), suggesting that this approach is a reliable, time-saving tool for routine identification of Candida species causing bloodstream infection.