We evaluated the impact of the implementation of a protocolized list of antimicrobial stewardship actionables based upon the results of the Biofire Filmarray pneumonia plus panel (FA-PP) on antimicrobial use in mechanically-ventilated critically ill patients with lower respiratory tract infection and its cost-effectiveness compared to the standard-of-care. Retrospective, pre- and post-FA-PP-implementation study including 213 consecutive patients, of which most (n = 198) were under empirical antimicrobial therapy (EAT) at the time of testing. Endotracheal aspirates were usually processed for microbiological testing. The primary study outcome was the number of participants with administration of antimicrobials or subjected to changes in EAT deemed to be appropriate. Secondary outcomes were the time to antimicrobial stewardship; and the total number of days on antimicrobial therapy. Conventional culture retrieved clinically significant results in 48/113 (42.4%) and 37/100 (37%) in the pre-FA-PP and post- FA-PP periods (P = 0.48). FA-PP increased the detection yield compared to conventional culture. The spectrum of bacterial species involved was comparable across both periods. Appropriate and proportionate adjustment of EAT was made more frequently in the post-FA-PP phase (54/89; 60.6%) than in the pre-FA-PP phase (55/109; 50.4%) (P = 0.15) and at earlier times. When considering the entire pre-FA-PP and post-FA-PP cohorts, no difference was noticed on duration of antimicrobial treatments (mean, 7.1 days vs. 7.6 days, respectively (P = 0.32). Nevertheless, adequate selection of patients for FA-PP testing enabled a reduction in the total number of antibiotic treatment days, with an Incremental Cost-Effectiveness Ratio of €151/day. Antimicrobial stewardship driven by the FA-PP panel results was sped up relative to that based upon standard practice with at least a comparable appropriateness and a rather negligible increase in costs.

Introduction Sexually transmitted infections (STIs) remain a major global public health concern, with a high proportion of asymptomatic cases. Undiagnosed infections may lead to significant clinical, economic, and epidemiological consequences. Patients with sterile pyuria and suspected urinary tract infection (UTI) represent a relevant target population for STI screening. Methods We evaluated the real-world performance of a targeted STI screening strategy based on urine sample pooling in patients with suspected UTI, genitourinary symptoms, leukocyturia, and negative urine culture. Results Over a 15-month period, 2019 urine samples were analysed using pooled PCR testing, identifying 212 STI-positive patients (10.5%). Chlamydia trachomatis was the most prevalent pathogen, followed by Trichomonas vaginalis, Mycoplasma genitalium, and Neisseria gonorrhoeae. Pooling did not compromise analytical sensitivity, with comparable cycle threshold values between pooled and individual samples. Conclusions Pooled PCR screening reduced testing volume while preserving diagnostic yield, supporting its use as an efficient and potentially cost-effective strategy for STI-screening.

This study aimed to assess the association between bacterial loads as quantified by the BIOFIRE® Filmarray Pneumonia Plus Panel (FA-PP) and clinically significant bacterial cultures in different clinical settings, taking into account the type of sample processed and the bacterial targets detected. A comprehensive search was conducted of the PubMed, EMBASE, and Web of Science databases up to November 2024. Pooled odds ratios (ORs) for binned values in genome copies/ml (gc/ml)(104, 105, 106, and ≥107) and their respective 95% confidence intervals (95% CI) are reported throughout the study. Heterogeneity across studies was assessed using the I2 statistic. Twenty-three observational studies comprising a total of 4581 patients and 5147 respiratory samples were finally included in the meta-analysis. Overall, pooled ORs for clinically significant culture results were 4.30 (95% CI, 2.53-7.31; P < 0.001) for ≥107 gc/ml, 1.33 (95% CI, 0.70-2.56; P=0.39) for 106, 0.42 (95% CI, 0.20-0.90; P=0.03) for 105, and 0.15 (95% CI, 0.07-0.37; P < 0.001) for 104 gc/ml. Subgroup analyses conducted according to the type of respiratory sample, bacterial target, and hospital admission ward yielded rather similar conclusions. The heterogeneity across studies was very high (I2 >80%). Our analyses suggested that values ≥107 gc/ml may be considered reliable indicators of clinically significant bacterial infection. Conversely, 104 gc/ml values likely reflect colonization. Intermediate values (105-106 gc/ml) pose a greater interpretative challenge. IMPORTANCE: The FA-PP assay has emerged as an ancillary tool for diagnosing lower respiratory tract infections and adjusting empirical antimicrobial therapies; consequently, it is being increasingly requested by clinicians. The current study fills a critical gap in the interpretation of quantitative data returned by the FA-PP for nosocomial bacterial targets. Assessment of the clinical relevance of FA-PP binned gc/ml values seems mandatory for clinical and therapeutic decision-making processes in patients with severe community-acquired or nosocomial pneumonia. Our analyses showed that values ≥107 gc/ml are consistently associated with a high probability of culture positivity, regardless of the respiratory sample type and the bacterial target considered. In contrast, values of 104 gc/ml likely reflect colonization. Our study emphasizes the need for well-designed and homogeneous studies to gauge the clinical relevance of intermediate FA-PP binned values (105 and 106 gc/ml).

Rapid galactomannan/galactomannoprotein-detecting tests, such as the AspLFD, may be useful for diagnosis of invasive pulmonary aspergillosis (IPA). Nevertheless, further real-life experience needs to be accrued to validate this assumption. In the current, single-center, retrospective study we compared the analytical performance of the AspLFD assay with that of the Platelia GM enzyme-linked immunosorbent assay (Bio-Rad; Marnes-la-Cocquette, France) and between AspLFD and the Aspergillus Galactomannan antigen VIRCLIA® Monotest (Vircell S.L., Granada, Spain) in two different periods using serum and respiratory specimens, including bronchoalveolar lavage (BAL), bronchoaspirates (BAS) and endotracheal aspirates (TA), and assessed its clinical value for the diagnosis of IPA. A total of 231 samples (129 respiratory specimens-including 71 BAS, 27 TA, 24 BAL, and 7 sputum samples-and 102 serum samples) were obtained from 145 consecutive patients who were screened for PA at the physician's request. Proven/probable IPA cases (n = 32) and non-PA cases (n = 92) were considered to assess the clinical performance of the AspLFD assay. Overall, the rate of positive results-mainly in respiratory specimens-was comparable between the AspLFD (46.3%) and the GM Platelia assays (46.3%) and between the AspLFD (24.2%) and the GM VIRCLIA® assay (30.1%), although discrepancies were observed in 10-16% of the specimens. The overall sensitivity of the AspLFD assay was 78.1% (95% CI, 61.2-89.0), and the specificity was 80.9% (95% CI, 71.5-87.7). The AspLFD assay could be of value in classifying probable IPA, even when using respiratory specimens other than BAL. Future studies are warranted to validate this assumption.

Introduction We hypothesized that the use of the BioFire® FilmArray Pneumonia Plus Panel (FA-PP) may help to assess the relationship between colonization and ventilator-associated lower respiratory infection (LRTI) caused by multidrug-resistant bacteria (MDRB). Methods A total of 376 patients underwent surveillance cultures for MDRB. Endotracheal aspirates were tested in parallel by the FA-PP and semiquantitative cultures for LRTI etiological diagnosis. Results A total of 131 patients had MDRB recovered from surveillance cultures (34.8%), of which 10 subsequently developed LRTI caused by a matched MDRB. In 2 patients, MDRB were detected by the FA-PP (blaOXA-48-producing Klebsiella pneumoniae and ESBL-producing K. pneumoniae) that were not recovered in culture. Among non-MDRB-colonized patients with LRTI due to MDRB (n=15) the FA-PP detected MDRB in 6 patients that were later recovered in screening cultures. Conclusion Incorporating FA-PP testing for LRTI diagnosis may be ancillary to assess the relationship between MDRB colonization and subsequent LRTI by matched strains.

To evaluate the diagnostic performance, clinical impact, and cost-effectiveness of a workflow combining EUCAST rapid antimicrobial susceptibility testing (RAST) with lateral flow immunochromatographic assays (LFIA) for resistance detection directly from positive blood cultures (BCs). A single-center, retrospective study including 179 monomicrobial bloodstream infection (BSI) episodes was conducted. RAST results were compared with broth microdilution (BMD) as the reference method. LFIA performance was assessed for the detection of extended-spectrum β-lactamases (ESBLs) and carbapenemases. The impact on antimicrobial therapy was analyzed at predefined time points. A cost-effectiveness analysis using a decision tree model compared three strategies: matrix-assisted laser desorption/ionization–time-of-flight mass spectrometry (MALDI-TOF MS) identification plus RAST, MALDI-TOF MS plus LFIA and RAST, and the FilmArray BCID2 molecular panel. Overall categorical agreement between RAST and definitive AST was 98.2

ABSTRACT Assessment of cytomegalovirus (CMV) cell-mediated immunity (CMV-CMI) using standardized, commercially available interferon-gamma release assays (IGRAs) may improve the clinical management of CMV infection in allogeneic hematopoietic stem cell transplant recipients (allo-HCT). Studies comparing the performance of CMV IGRA assays have been conducted in this setting, revealing frequent discrepancies between assays. Here, we compared the performance of a newly released VIDAS CMV IGRA (bioMérieux) and the T-SPOT. CMV (Oxford Immunotec) was evaluated in a cohort of 85 allo-HCT recipients who received letermovir prophylaxis. A total of 107 whole blood samples were collected at either day +100 ( n = 53) or day +180 ( n = 54) after allo-HCT and analyzed in parallel. A moderate qualitative agreement between assays was observed (Cohen’s kappa coefficient, 0.47; 95% CI, 0.30–0.63). Discrepant results were obtained in 29 specimens, most of which were collected at day +100. A moderate correlation (rho, 0.54; P < 0.001) was observed between T-SPOT pp65-SPC and IFN-γ levels measured by the VIDAS CMV assay, whereas the correlation was weaker for T-SPOT IE-1 SPC and VIDAS IFN-γ levels (rho, 0.32; P < 0.001). The previously described booster effect of CMV DNAemia on the magnitude of CMV-CMI was captured by the VIDAS CMV assay. Neither the qualitative nor the quantitative results obtained with either IGRA predicted protection from CMV DNAemia following LMV discontinuation. While our data support the validity of the VIDAS CMV assay for the assessment of CMV-CMI in allo-HCT, they reinforce the idea that results from commercially available IGRA assays are not interchangeable, particularly in allo-HCT recipients with impaired CMV-CMI reconstitution. IMPORTANCE This is the first study comparing a new interferon-gamma release assay (IGRA), the VIDAS cytomegalovirus (CMV), performed on whole blood and based on an enzyme-linked immunofluorescent assay detection technique, with a commercially available ELISpot assay (T-SPOT CMV) for measuring CMV-specific T-cell responses (CMV-CMI). Our cohort included allogeneic hematopoietic stem cell transplant recipients who underwent letermovir prophylaxis. In this clinical setting, tailoring the duration of LMV prophylaxis based on CMV-CMI at the time of drug discontinuation has emerged as a promising application of these assays. Our data revealed substantial qualitative and quantitative differences between the assays, which should be taken into consideration in future observational studies or clinical trials assessing the utility of IGRAs for individualizing LMV prophylaxis duration.

Introduction The Aspergillus Galactomannan Antigen VirClia® Monotest (Vircell S.L., Granada, Spain) has been implemented in many laboratories in Spain; however, its use has not been clinically validated for the management of invasive pulmonary aspergillosis (IPA). Here, we gathered information on current practices related to the use of the VirClia® GM assay in Spanish hospitals. Methods Spanish laboratory users of the VirClia® assay were invited to respond to a standardized questionnaire. Results The questionnaire was completed in full by 35 out of 54 (64.8%) invited microbiology laboratories and by 14 clinicians. In addition to serum and bronchoalveolar lavages, non-validated sample types such as bronchoaspirates and endotracheal aspirates are used by around 20% of laboratories. Most laboratories (94.3%) report qualitative results using a threshold for positivity of >0.2, irrespective of the sample type and the patient's underlying condition, which is considered by most responding clinicians as a mycological criterion for probable IPA. Conclusion The current survey mainly reflects the heterogeneity in the use and interpretation of the VirClia® GM immunoassay, which, in the absence of clinically validated thresholds for probable IPA, introduces uncertainty and may lead to misinterpretations.

Timely knowledge of local epidemiology is essential for guiding appropriate antibiotic therapy in severe infections such as bloodstream infections (BSI). In 2024, we developed “eBIMIC”, a web-based application that enables real-time parameterized consultation of cumulative antimicrobial susceptibility data base on demographic and microbiological parameters. Avaliable to all clinicians within the Clínico-Malvarrosa Health Department (Valencia, Spain). This study evaluated its potential impact on optimizing antibiotic therapy in BSI patients admitted from the Emergency Department (ED). We retrospectively analyzed 212 adult patients with positive blood cultures from the ED between January and December 2023. Empirical and semi-targeted treatments were compared with eBIMIC-based susceptibility data using patient sex, age, ED location, and Gram stain results (for empirical therapy), or species identification (for semi-targeted therapy). A susceptibility rate ≥ 85

Direct matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) enables rapid identification of microorganisms in urinary tract infections (UTIs), accelerating diagnosis and guiding early antimicrobial therapy alongside conventional culture. However, there is no universally established threshold for significant bacteriuria determined by flow cytometry in clinical decision-making. This study analyzed 652 urine samples from suspected UTI patients at Hospital Clínico Universitario de Valencia (Jan 2023-Nov 2024). Flow cytometry was used to determine bacterial load (bacteria/µL) and Gram staining before MALDI-TOF MS and culture processing. The overall concordance between MALDI-TOF MS and culture was 96.5%. Samples successfully identified by MALDI-TOF MS had a significantly higher median bacterial load than those not identified. Receiver operating characteristic (ROC) analysis established 15,606 bacteria/µL as the optimal cut-off for MALDI-TOF MS processing (sensitivity: 83.3%, specificity: 50%, PPV: 70.9%, NPV: 67.2%). This differs from the conventional ≥ 10⁵ CFU/mL threshold, suggesting MALDI-TOF MS remains effective at lower bacterial loads, thus improving resource efficiency. Additionally, lateral flow immunochromatographic (LFIC) assays facilitated rapid detection of resistance mechanisms, aiding empirical antimicrobial therapy. Our findings support the utility of flow cytometry in efficiently selecting candidate samples for MALDI-TOF MS, enhancing clinical decision-making in UTI management.

PURPOSE:To compare the diagnostic performance of BD MAX™ Enteric Panels and the Luminex NxTAG® Gastrointestinal Pathogen Panel (GPP) for the detection of enteric pathogens under routine clinical conditions. METHODS:A prospective single-center study analyzed 165 stool samples (one per patient) from individuals with suspected gastrointestinal infection attending the Clínico-Malvarrosa Health Department (Valencia, Spain) between October and November 2023. Samples tested using all BD MAX™ enteric panels (bacterial, viral, and Clostridioides difficile panels) were also processed by Luminex NxTAG® GPP assay. Positive Percentage Agreement (PPA), Negative Percentage Agreement (NPA), Cohen's κ index were calculated. Discrepant results were investigated using the VIASURE real-time PCR and targeted Next-Generation Sequencing, as appropriate. RESULTS:Among the 165 samples analyzed, 107 (64.8%) were positive for at least one pathogen by either method, with norovirus (n = 40) and Clostridioides difficile (n = 18) being the most frequently detected targets. Overall, both assays exhibited moderate initial agreement (PPA 69.3%, NPA 90.6%, κ = 0.56), with an average PPA of 78.6%. PPA exceeded 85% for most targets, except for sapovirus. Salmonella spp., and Shiga toxin-producing E. coli (stx1, stx2) (STEC) accounted for most discordant results, often associated with low pathogen loads or analytical variability. After discrepancy resolution, both assays demonstrated comparable diagnostic performance, with a substantial concordance of (κ = 0.79 and 0.77, respectively). CONCLUSION:BD MAX™ and Luminex NxTAG® GPP demonstrated comparable accuracy in detecting enteric pathogens, supporting their use in cost-effective, culture-independent molecular diagnosis and their integration within microbiological diagnostic stewardship programs.

Cytomegalovirus (CMV) infections remain a major complication following allogeneic hematopoietic stem cell transplantation (allo-HCT), with refractory infections associated with increased morbidity and mortality. Machine learning (ML) approaches may improve risk stratification and clinical management of CMV infections. This retrospective multicenter study analyzed 933 allo-HCT recipients from 21 Spanish centers (2014-2018) using data from the Spanish Hematopoietic Transplantation and Cell Therapy Group registry. Three ML models were developed to predict: (1) CMV DNAemia occurrence, (2) clinically significant CMV infection (csCMV-I), and (3) refractory CMV infection (CMV-R). Six supervised ML algorithms were evaluated using 25 repeated fivefold stratified cross-validation, including Random Forest, Support Vector Machine, Decision Trees, XGBoost, Elastic Net, and PLS-Logistic Regression. CMV DNAemia occurred in 493 recipients (53%), with 356 (72%) developing CsCMV-I and 91 (26%) progressing to CMV-R. The optimal models achieved: XGBoost for CMV DNAemia and CsCMV-I prediction (sensitivity 0.97) and SVM for CMV-R prediction (sensitivity 0.58). Key predictive features included recipient CMV serostatus, conditioning regimens, GvHD occurrence, recipient characteristics, and immunosuppressive protocols, with distinct signatures for each outcome. ML models successfully identified distinct clinical profiles associated with different CMV outcomes in allo-HCT recipients, achieving high sensitivity but moderate discriminatory capacity (AUC 0.55-0.67). Despite limitations including pre-letermovir era data, this work establishes a foundation for precision risk stratification as a complement to-not replacement for-current prophylaxis strategies. Prospective validation in contemporary cohorts is needed before clinical implementation.

CNS complications (CNSC) may occur in a significant proportion of patients after allogeneic haematopoietic cell transplantation (allo-HCT). They can be differentiated into infectious and non-infectious CNSC, such as vascular pathologies (e.g., bleeding, stroke), drug-related abnormalities, and CNS relapse of the underlying malignancy. Initiation of prompt and adequate diagnostics - mainly neuroimaging and cerebrospinal fluid (CSF) analyses - and treatment are crucial to improve the prognosis. Here, we report on the epidemiology, outcome, and neuroimaging of CNSC after allo-HCT. We also provide an overview of the special considerations for children with these complications. These findings and recommendations were developed during a multidisciplinary EBMT harmonisation workshop. Novel diagnostics, such as CSF next-generation sequencing (NGS) and special MRI sequences, are emerging and may improve the accuracy of diagnosis for selected CNSC. The prognosis of post-transplant CNSC is heterogeneous, with drug-related CNSC mainly having a favourable prognosis, while the outcome of CNS bleeding, CNS leukaemia, and cerebral fungal disease is still frequently dismal. A high level of awareness is crucial in the clinical routine - especially in distinct subgroups such as paediatrics - besides the development of novel algorithms, diagnostics, and treatment approaches to improve the outcome.

We investigated whether plasma cytomegalovirus (CMV) IL-10 (cmvIL-10) levels could serve as a biomarker of active CMV replication in allogeneic hematopoietic transplant recipients (allo-HCT) in the presence or absence of letermovir (LMV) prophylaxis. A total of 189 leftover plasma samples that tested positive for CMV DNA (Alinity m CMV assay), representing 33 episodes of CMV DNAemia were run on a laboratory-developed enzyme-linked immunosorbent assay for cmvIL-10 quantification. Eighteen episodes developed during LMV prophylaxis. Overall, 16 episodes of CMV DNAemia were classified as clinically significant (CsCMVi). There was an overall very weak correlation between the two biomarkers (Rho = 0.10; p = 0.16). Overall, the median cmvIL-10 area under the curve (AUC) until CMV DNA levels reached their peak was significantly higher (p < 0.001) in CsCMVi episodes than in non-CsCMVi episodes. cmvIL-10 AUC between Days 14 and 23 after allo-HCT (AUC₁₄₋₂₃) values were significantly higher in CsCMVi episodes compared with non-CsCMVi episodes among patients receiving LMV therapy (p = 0.008). An AUC₁₄₋₂₃ cutoff value of log10 3.06 discriminated anticipately between CsCMVi and non-CsCMVi with a sensitivity and specificity of 100%. Plasma cmvIL-10 levels may reflect true CMV replication and thus provide a unique perspective on viral dynamics, serving as an ancillary marker to CMV DNA monitoring.

Introduction Studies assessing SARS-CoV-2 antibodies and functional T-cell responses in hematological patients following receipt of a three-dose mRNA vaccine schedule have yielded conflicting results. Methods We conducted a retrospective observational study in which we measured SARS-CoV-2-S-directed cytokine-producing CD8+ and CD4+ T cells by flow cytometry and anti-receptor-binding domain (RBD) total antibodies in 32 hematological patients, including 10 allogeneic hematopoietic stem cell transplant (allo-HCT) recipients and 22 non-transplanted individuals. Immunological testing was performed after the second COVID-19 mRNA vaccine dose (Post-2D), prior to the third dose (Pre-3D), and after the third dose (Post-3D). Results At Post-2D, 72.4%, 44.8%, and 37.9% of participants had detectable IFN-γ-, TNF-α-, and IFN-γ/TNF-α-producing CD8+ T cells, respectively. A decrease in the rate of detectable and frequencies of monofunctional and bifunctional SARS-CoV-2-S CD8+ T-cell responses was observed at Pre-3D. By contrast, the number of participants displaying detectable cytokine-producing CD4+ T-cell responses and their frequencies were rather conserved at all testing times. Receiving a 3D had no significant impact on the rate of detection and frequencies of monofunctional and bifunctional SARS-CoV-2-S-directed T-cell subsets. Anti-RBD total antibody responses were detected in approximately half of participants at all time points. Overall, anti-RBD antibody levels decreased at Pre-3D and then increased following the 3D. Conclusion Administration of the 3D may have a limited impact on both cellular and humoral immune responses in a substantial proportion of hematological patients. These findings highlight the heterogeneity of vaccine-induced immunity and support the role of combined immune monitoring and alternative protective strategies for selected patients.

We aimed to evaluate the cost-effectiveness of screening for sexually transmitted infections (STI), Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, and Trichomonas vaginalis in patients with suspected urinary tract infection (UTI) but negative urine cultures, using a pooled sampling method. A cohort of 200 patients was analyzed. A decision tree model based on cost-effectiveness was used to evaluate the following five diagnostic strategies: (A) no screening;(B) screening only men;(C) screening only women;(D) screening men and women with high leukocyte counts (>70cells/µL);(E) screening all men and women. The pooling method reduced reagent testing costs by 75 %. The most cost-effective strategy was screening men and women with high leukocyte counts, yielding an incremental cost-effectiveness ratio of 489.05euros. STI screening using pooled midstream urine samples in patients with suspected UTI and negative urine cultures is cost-effective, particularly when targeting individuals with high leukocyte counts. This approach optimizes resource use and improves early STI detection.

We investigated whether the results returned by the Biofire® Pneumonia Plus Panel (FA-PP) in lower respiratory tract specimens (LRT) specimens may identify patients who should be targeted for Herpes simplex virus (HSV) DNA testing. We included 35 adult ICU patients who underwent protocolized HSV DNA testing in LRT and/or plasma specimens by real-time PCR. Of these, one patient underwent allogeneic hematopoietic cell transplantation, one a kidney transplantation and one was under CAR-T cell therapy. Twenty-three of the 33 patients (69.6 %) had HSV-type 1 (HSV-1) DNA detected in LRT specimens (median viral load: 5.67 log10 copies/ml). Viral DNA was detected in 12/14 (85 %) plasma samples (median, 3.4 log10 copies/ml) from patients with HSV-1 DNA present in LRT specimens. Patients testing positive by the FA-PP had a non-significant (P = 0.28) higher rate of HSV-1 DNA detection (10/13; 77 %) compared with patients returning negative results (9/16; 56 %). In conclusion, requests for HSV DNA testing in ICU patients should not depend on the results of conventional culture methods nor those provided by the FA-PP.