European Journal of Clinical Microbiology & Infectious Diseases最新文献

Purpose: Benzylpenicillin is regaining attention as a treatment option for susceptible S. aureus, including in severe invasive diseases such as blood stream infections. Timely and reliable susceptibility determination is essential to support its use in clinical practice. In this study, we assessed the EUCAST-recommended methodology of interpreting zone edges in a national multicenter trial.

Methods: In total, nine microbiology laboratories in Austria participated. Each center received 10 isolates in blinded duplicates, all with inhibition zones of ≥ 26 mm. Three were blaZ-positive with sharp edges and seven were blaZ-negative with fuzzy edges. Benzylpenicillin susceptibility testing according to EUCAST guidelines using 1 unit discs was performed by two independent technicians in duplicate on two separate days. All plates were interpreted by two different assessors generating a total of 1440 data points.

Results: Overall, 85.5% of all interpretations were correct. Both, major and very major errors occurred. There was high variability between laboratories with overall accuracy ranging from 61.9% to 100%. There were statistically significant differences in the average inhibition zone between MH agars from different manufacturers. Laboratories using agars giving rise to a smaller average inhibition zone (i.e. lower diffusion of benzylpenicillin) performed less well. Laboratories with the methodology implemented performed better than those without experience.

Conclusion: In summary, our study demonstrates that benzylpenicillin susceptibility testing using the EUCAST-recommended methodology is feasible, but accurate and reproducible assessment of zone edges requires both experience and optimal materials. Thorough validation of locally used materials is therefore essential before implementing this approach for routine use.

Background: Enterococcus faecalis (E. faecalis) infective endocarditis (EFIE) treatment consists of a penicillin backbone and a synergistic agent (gentamicin or ceftriaxone). Due to the instability of aminopenicillins in continuous infusion in the outpatient context, benzylpenicillin is used as an alternative to ampicillin, though concern regarding reduced synergy with ceftriaxone has emerged. Clinical Laboratory Standards Institute (CLSI) provides MIC breakpoints for penicillin and ampicillin. European Committee for Antimicrobial Susceptibility Testing (EUCAST) guidelines only provide breakpoints for ampicillin. We evaluated the changing antimicrobial prescribing practices, and laboratory reporting (from CLSI to EUCAST guidelines) related to EFIE treatment and outcomes at our centre.

Methods: This was a retrospective study at Monash Health, Melbourne. Adult patients aged ≥ 18 years, who were treated for EFIE from 2014 to 2022, were included. Univariable associations were evaluated (p < 0.05).

Results: 104 patients treated for EFIE were included. Following EUCAST guideline implementation, there was a significant increase in ampicillin-based regimens prescribed as initial antimicrobials for directed EFIE therapy (64.3 to 82.3% p = 0.00135); benzylpenicillin regimens decreased across the same period (36.7% to 8.1%, p = 0.0007). In patients who received combination therapy, ceftriaxone use increased in the EUCAST period (p < 0.0001). Vancomycin prescriptions as subsequent regimen increased in the EUCAST period (0 to 19.3%, p = 0.0071). Ampicillin or benzylpenicillin monotherapy prescription as initial EFIE treatment reduced when comparing CLSI to EUCAST periods (p = 0.00001).

Conclusion: There is significant heterogeneity in the antimicrobials prescribed for EFIE at our centre, reflective of evidence that emerged over the last decade, changes in susceptibility testing and reporting and lack of randomised control trial (RCT) data supporting any one regimen. RCT data is required to further inform and refine directed EFIE treatment recommendations.

Background: (Candida glabrata C. glabrata) is classified as a high-priority pathogen by the World Health Organization (WHO). It causes mucosal and deep infections in immunocompromised individuals, yet its diagnosis currently relies on slow culture processes. This highlights the urgent need for rapid and accurate detection methods.

Methods: Ten primers targeting different regions of the C. glabrata ITS2 gene were designed to create a multiple cross displacement amplification (MCDA) assay coupled with a nanoparticle lateral flow biosensor (LFB). Following optimisation of temperature and time, the multiple cross displacement amplification coupled with lateral flow biosensor (MCDA-LFB) system was employed to detect C. glabrata DNA in clinical specimens.

Results: Under optimal conditions (63 °C, 40 min), the C. glabrata-MCDA-LFB assay achieved a limit of detection (LoD) of 10 fg/µL.The assay successfully detected all C. glabrata strains tested and demonstrated no cross-reactivity with non-C. glabrata isolates. Findings showed that the C. glabrata-MCDA-LFB assay promptly and successfully detected all 57 C. glabrata-positive samples among 240 clinical specimens identified by traditional culture methods. The entire process, including sample processing (20 min), the MCDA reaction (40 min) and result documentation (2 min), was completed within 62 min.

Conclusion: The C. glabrata-MCDA-LFB assay developed in this study is a rapid, simplified, sensitive and specific technique that is straightforward to use. It can be used to screen for or diagnose C. glabrata infections in clinical settings, particularly in regions with limited resources.

Our aim was to determine risk factors of enterococcal bacteraemia (EB) in urology. In a prospective study including all positive blood cultures (PBC) in urology for 18 months in five institutions, one hundred seventy-six PBC diagnosed, including 111 cases related to Gram negative bacilli (63%), 32 EB (18%) and 33 cases related to other pathogens (19%). The main characteristic of EB was their occurrence exclusively in male gender. In logistic regression, EB appeared to be associated with transurethral resection of the prostate: adjusted odds ratio (AOR) [95% CI]: 3.75 [1.30-10.78].

Background: Post-lung transplantation pneumonia (pLuTP) is among the most frequent complications following lung transplantation, predominantly caused by Gram-negative bacteria (GNB). The emergence of multidrug-resistant (MDR) non-fermenting GNB as aetiological agents of pLuTP represents a major therapeutic challenge due to limited treatment options.

Methods: We present a retrospective case series describing 20 episodes of pLuTP successfully treated with cefiderocol.

Results: Thirteen patients, with a median age of 56 years (IQR 44-59), experienced a total of 20 episodes of pLuTP. In 3 cases (25.0%), polymicrobial pneumonia was diagnosed. Acinetobacter baumannii was isolated in 13/20 episodes (65.0%), followed by Pseudomonas aeruginosa (6/20, 30.0%), Achromobacter xylosoxidans and Klebsiella pneumoniae (2/20, 10.0% each). Cefiderocol was administered in all episodes: as monotherapy in 5/20 cases (25.0%), in combination with high-dose ampicillin/sulbactam in 7/20 cases (35.0%), aminoglycosides or intravenous colistin (2/20, 10.0% each), and other regimens in the remaining 4/20 cases (20.0%). Clinical cure was achieved in 17/20 cases (85.0%). Microbiological eradication was not achieved in any case. Relapse occurred in 4/20 episodes (20.0%), with no evidence of in vitro cefiderocol resistance. No major adverse events were reported.

Conclusions: Cefiderocol may represent a valuable therapeutic option for managing pLuTP caused by difficult-to-treat GNB in lung transplant recipients.

Saprochaete species are emerging fungal pathogens, particularly affecting immunocompromised individuals, with clinical manifestations ranging from superficial to invasive infections. We present three cases of pediatric Saprochaete spp. infections, detailing clinical presentation, diagnostic workup, and treatment strategies. Two patients with acute myeloid leukemia developed bloodstream infections with Saprochaete clavata; both required prolonged antifungal therapy due to deep organ involvement, and one experienced relapse after treatment discontinuation. The third case involved a patient with cystic fibrosis, in whom Saprochaete capitata was isolated from sputum; she improved with antifungal therapy and had no relapse. Saprochaete spp. infections in pediatric populations present diagnostic and therapeutic challenges. Further research is needed to optimize management strategies and improve patient outcomes.

Purpose: Current treatment options for infections caused by vancomycin-resistant (VR) Enterococcus faecium remain limited and often suboptimal. This study investigates the in vitro activity of combination therapies involving fosfomycin and oxazolidinones (linezolid, contezolid, delpazolid, and sutezolid) against five vanA and five vanB E. faecium isolates obtained from blood cultures.

Methods: The synergistic activity of fosfomycin combined with each oxazolidinone was assessed using checkerboard and time-kill assays.

Results: Synergistic interactions were demonstrated with all fosfomycin-oxazolidinone combinations, although the effect was more consistent with delpazolid. In some cases (one for contezolid, three for linezolid, four for sutezolid), the interaction was additive rather than synergistic. Synergy was mainly driven by a significant reduction in fosfomycin minimum inhibitory concentration (MIC), up to 16-fold, while decreases in oxazolidinone MIC were modest. Time-kill assays performed on representative isolates Ef-3 (vanB) and Ef-10 (vanA) confirmed the synergistic interactions, showing a reduction in viable cell counts after 24 h.

Conclusion: Our findings provide preclinical evidence supporting the use of fosfomycin in combination with novel oxazolidinones as a promising therapeutic strategy against VR E. faecium infections.