Project description:Rationale: Aspergillus infection in patients with suspected ventilator-associated pneumonia remains uncharacterized because of the absence of a disease definition and limited access to sensitive diagnostic tests.Objectives: To estimate the prevalence and outcomes of Aspergillus infection in adults with suspected ventilator-associated pneumonia.Methods: Two prospective UK studies recruited 360 critically ill adults with new or worsening alveolar shadowing on chest X-ray and clinical/hematological parameters supporting suspected ventilator-associated pneumonia. Stored serum and BAL fluid were available from 194 nonneutropenic patients and underwent mycological testing. Patients were categorized as having probable Aspergillus infection using a definition comprising clinical, radiological, and mycological criteria. Mycological criteria included positive histology or microscopy, positive BAL fluid culture, galactomannan optical index of 1 or more in BAL fluid or 0.5 or more in serum.Measurements and Main Results: Of 194 patients evaluated, 24 met the definition of probable Aspergillus infection, giving an estimated prevalence of 12.4% (95% confidence interval, 8.1-17.8). All 24 patients had positive galactomannan in serum (n = 4), BAL fluid (n = 16), or both (n = 4); three patients cultured Aspergillus sp. in BAL fluid. Patients with probable Aspergillus infection had a significantly longer median duration of critical care stay (25.5 vs. 15.5 d, P = 0.02). ICU mortality was numerically higher in this group, although this was not statistically significant (33.3% vs. 22.8%; P = 0.23).Conclusions: The estimated prevalence for probable Aspergillus infection in this geographically dispersed multicenter UK cohort indicates that this condition should be considered when investigating patients with suspected ventilator-associated pneumonia, including patient groups not previously recognized to be at high risk of aspergillosis.
Project description:Background Data on incidence of ventilator-associated pneumonia (VAP) and invasive pulmonary aspergillosis in patients with severe SARS-CoV-2 infection are limited. Methods We conducted a monocenter retrospective study comparing the incidence of VAP and invasive aspergillosis between patients with COVID-19-related acute respiratory distress syndrome (C-ARDS) and those with non-SARS-CoV-2 viral ARDS (NC-ARDS). Results We assessed 90 C-ARDS and 82 NC-ARDS patients, who were mechanically ventilated for more than 48 h. At ICU admission, there were significantly fewer bacterial coinfections documented in C-ARDS than in NC-ARDS: 14 (16%) vs 38 (48%), p?<?0.01. Conversely, significantly more patients developed at least one VAP episode in C-ARDS as compared with NC-ARDS: 58 (64%) vs. 36 (44%), p?=?0.007. The probability of VAP was significantly higher in C-ARDS after adjusting on death and ventilator weaning [sub-hazard ratio?=?1.72 (1.14–2.52), p?<?0.01]. The incidence of multi-drug-resistant bacteria (MDR)-related VAP was significantly higher in C-ARDS than in NC-ARDS: 21 (23%) vs. 9 (11%), p?=?0.03. Carbapenem was more used in C-ARDS than in NC-ARDS: 48 (53%), vs 21 (26%), p?<?0.01. According to AspICU algorithm, there were fewer cases of putative aspergillosis in C-ARDS than in NC-ARDS [2 (2%) vs. 12 (15%), p?=?0.003], but there was no difference in Aspergillus colonization. Conclusions In our experience, we evidenced a higher incidence of VAP and MDR-VAP in C-ARDS than in NC-ARDS and a lower risk for invasive aspergillosis in the former group.
Project description:We hypothesized that invasive pulmonary aspergillosis (IPA) may generate a distinctive proteomic signature in plasma and bronchoalveolar lavage (BAL). Proteins in plasma and BAL from two neutropenic rabbit models of IPA and Pseudomonas pneumonia were analyzed by SELDI-TOF MS. Hierarchical clustering analysis of plasma time course spectra demonstrated two clusters of peaks that were differentially regulated between IPA and Pseudomonas pneumonia (57 and 34 peaks, respectively, p<0.001). PCA of plasma proteins demonstrated a time-dependent separation of the two infections. A random forest analysis that ranked the top 30 spectral points distinguished between late Aspergillus and Pseudomonas pneumonias with 100% sensitivity and specificity. Based on spectral data analysis, three proteins were identified using SDS-PAGE and LC/MS and quantified using reverse phase arrays. Differences in the temporal sequence of plasma haptoglobin (p<0.001), apolipoprotein A1 (p<0.001) and transthyretin (p<0.038) were observed between IPA and Pseudomonas pneumonia, as was C-reactive protein (p<0.001). In summary, proteomic analysis of plasma and BAL proteins of experimental Aspergillus and Pseudomonas pneumonias demonstrates unique protein profiles with principal components and spectral regions that are shared in early infection and diverge at later stages of infection. Haptoglobin, apolipoprotein A1, transthyretin, and C-reactive protein are differentially expressed in these infections suggesting important contributions to host defense against IPA.
Project description:To assess whether transcriptional differences exist in the epithelial tissue and the inflammatory infiltrate of invasive Aspergillus tracheobronchitis in patients with severe influenza or severe COVID-19, we performed GeoMx spatial transcriptomics on four biopsy samples in total: two of patients with influenza-associated pulmonary aspergillosis (IAPA) and two of patients with COVID-19-associated pulmonary aspergillosis (CAPA). Several regions of interest (ROIs) were delineated in each biopsy sample, and transcriptomic data was derived of each of these ROIs using GeoMx with a whole transcriptome atlas with SARS-CoV-2 spike-in.
Project description:BackgroundDifferentiating Ventilator-Associated Tracheobronchitis (VAT) from Ventilator-Associated Pneumonia (VAP) may be challenging for clinicians, yet their management currently differs. In this study, we evaluated the accuracy of the Clinical Pulmonary Infection Score (CPIS) to differentiate VAT and VAP.MethodsWe performed a retrospective analysis based on the data from 2 independent prospective cohorts. Patients of the TAVeM database with a diagnosis of VAT (n = 320) or VAP (n = 369) were included in the derivation cohort. Patients admitted to the Intensive Care Centre of Lille University Hospital between January 1, 2016 and December 31, 2017 who had a diagnosis of VAT (n = 70) or VAP (n = 139) were included in the validation cohort. The accuracy of the CPIS to differentiate VAT from VAP was assessed within the 2 cohorts by calculating sensitivity and specificity values, establishing the ROC curves and choosing the best threshold according to the Youden index.ResultsThe areas under ROC curves of CPIS to differentiate VAT from VAP were calculated at 0.76 (95% CI [0.72-0.79]) in the derivation cohort and 0.67 (95% CI [0.6-0.75]) in the validation cohort. A CPIS value ≥ 7 was associated with the highest Youden index in both cohorts. With this cut-off, sensitivity and specificity were respectively found at 0.51 and 0.88 in the derivation cohort, and at 0.45 and 0.89 in the validation cohort.ConclusionsA CPIS value ≥ 7 reproducibly allowed to differentiate VAT from VAP with high specificity and PPV and moderate sensitivity and NPV in our derivation and validation cohorts.
Project description:Ventilator-associated pneumonia occurs in patients who have been intubated for at least 2–3 days with significant exposure to hospital-acquired organisms. Treatment should be initiated rapidly and cover Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumonia, and methicillin-resistant Staphylococcus aureus(MRSA). Within 72 h or with the availability of culture results, antibiotics should be narrowed. Active research is on-going to identify patients at risk for ventilator-associated complications and to minimize the likelihood of infection in these patients.
Project description:Aspergillus co-infection in patients with severe coronavirus disease 2019 (COVID-19) pneumonia, leading to acute respiratory distress syndrome, has recently been reported. To date, 38 cases have been reported, with other cases most likely undiagnosed mainly due to a lack of clinical awareness and diagnostic screening. Importantly, there is currently no agreed case definition of COVID-19 associated invasive pulmonary aspergillosis (CAPA) that could aid in the early detection of this co-infection. Additionally, with the global emergence of triazole resistance, we emphasize the importance of antifungal susceptibility testing in order to ensure appropriate antifungal therapy. Herein is a review of 38 published CAPA cases, which highlights the diagnostic and therapeutic challenges posed by this novel fungal co-infection.
Project description:Abstract From manuscript: Incidences of invasive pulmonary aspergillosis, an infection caused predominantly by Aspergillus fumigatus, have increased due to the growing number of immunocompromised individuals. While A. fumigatus is reliant upon deficiencies in the host to facilitate invasive disease, the distinct mechanisms that govern the host-pathogen interaction remain enigmatic, particularly in the context of distinct immune modulating therapies. To gain insights into these mechanisms, RNA-Seq technology was utilized to sequence RNA derived from lungs of 2 clinically relevant, but immunologically distinct murine models of IPA on days 2 and 3 post inoculation when infection is established and active disease present. Our findings identify notable differences in host gene expression between the chemotherapeutic and steroid models at the interface of immunity and metabolism. RT-qPCR verified model specific and nonspecific expression of 23 immune-associated genes. Deep sequencing facilitated identification of highly expressed fungal genes. We utilized sequence similarity and gene expression to categorize the A. fumigatus putative in vivo secretome. RT-qPCR suggests model specific gene expression for nine putative fungal secreted proteins. Our analysis identifies contrasting responses by the host and fungus from day 2 to 3 between the two models. These differences may help tailor the identification, development, and deployment of host- and/or fungal-targeted therapeutics.