Project description:BackgroundMetabolic changes induced by the host immune response to pathogens found in patients with community-acquired pneumonia (CAP) may provide insight into its pathogenesis. In this study, we characterized differences in the host metabolic response to common CAP-associated pathogens.MethodTargeted metabolomic profiling was performed on serum samples obtained from hospitalized CAP patients (n = 119) at admission. We quantified 347 unique metabolites across multiple biochemical classes, including amines, acylcarnitines, and signaling lipids. We evaluated if unique associations between metabolite levels and specific CAP-associated pathogens could be identified.ResultsSeveral acylcarnitines were found to be elevated in C. burnetii and herpes simplex virus and lowered in M. pneumoniae as compared to other pathogens. Phenylalanine and kynurenine were found elevated in L. pneumophila as compared to other pathogens. S-methylcysteine was elevated in patients with M. pneumoniae, and these patients also showed lowered cortisol levels in comparison to almost all other pathogens. For the herpes simplex virus, we observed a unique elevation of eicosanoids and several amines. Many lysophosphatidylcholines showed an altered profile in C. burnetii versus S. pneumoniae, L. pneumophila, and respiratory syncytial virus. Finally, phosphatidylcholines were negatively affected by the influenza virus in comparison to S. pneumoniae.ConclusionsIn this exploratory analysis, metabolites from different biochemical classes were found to be altered in serum samples from patients with different CAP-associated pathogens, which may be used for hypothesis generation in studies on differences in pathogen host response and pathogenesis of CAP.
Project description:BackgroundCommunity-acquired pneumonia (CAP) can be caused by a variety of pathogens, of which Streptococcus pneumoniae, Influenza and currently SARS-CoV-2 are the most common. We sought to identify shared and pathogen-specific host response features by directly comparing different aetiologies of CAP.MethodsWe measured 72 plasma biomarkers in a cohort of 265 patients hospitalized for CAP, all sampled within 48 hours of admission, and 28 age-and sex matched non-infectious controls. We stratified the biomarkers into several pathophysiological domains- antiviral response, vascular response and function, coagulation, systemic inflammation, and immune checkpoint markers. We directly compared CAP caused by SARS-CoV-2 (COVID-19, n=39), Streptococcus pneumoniae (CAP-strep, n=27), Influenza (CAP-flu, n=22) and other or unknown pathogens (CAP-other, n=177). We adjusted the comparisons for age, sex and disease severity scores.FindingsBiomarkers reflective of a stronger cell-mediated antiviral response clearly separated COVID-19 from other CAPs (most notably granzyme B). Biomarkers reflecting activation and function of the vasculature showed endothelial barrier integrity was least affected in COVID-19, while glycocalyx degradation and angiogenesis were enhanced relative to other CAPs. Notably, markers of coagulation activation, including D-dimer, were not different between the CAP groups. Ferritin was most increased in COVID-19, while other systemic inflammation biomarkers such as IL-6 and procalcitonin were highest in CAP-strep. Immune checkpoint markers showed distinctive patterns in viral and non-viral CAP, with highly elevated levels of Galectin-9 in COVID-19.InterpretationOur investigation provides insight into shared and distinct pathophysiological mechanisms in different aetiologies of CAP, which may help guide new pathogen-specific therapeutic strategies.FundingThis study was financially supported by the Dutch Research Council, the European Commission and the Netherlands Organization for Health Research and Development.
Project description:We aimed to examine the differences in the gene expression profile in peripheral blood at hospital admission between patients with community-acquired pneumonia (CAP) who died and survived during hospitalization. Whole blood samples for genome expression profile analysis were obtained within 24 hours of hospital admission. Gen set enrichment analysis (GSEA) identified gene sets positively enriched in the patients who survived, mainly related with interferon- alpha response, apoptosis, and sex hormones pathways. Similarly, GSEA identified gene sets positively enrichment for the patients who died (oxidative stress, endoplasmic reticulum stress, oxidative phosphorylation, and angiogenesis pathways).
Project description:Community-acquired pneumonia causes great mortality and morbidity and high costs worldwide. Empirical selection of antibiotic treatment is the cornerstone of management of patients with pneumonia. To reduce the misuse of antibiotics, antibiotic resistance, and side-effects, an empirical, effective, and individualised antibiotic treatment is needed. Follow-up after the start of antibiotic treatment is also important, and management should include early shifts to oral antibiotics, stewardship according to the microbiological results, and short-duration antibiotic treatment that accounts for the clinical stability criteria. New approaches for fast clinical (lung ultrasound) and microbiological (molecular biology) diagnoses are promising. Community-acquired pneumonia is associated with early and late mortality and increased rates of cardiovascular events. Studies are needed that focus on the long-term management of pneumonia.
Project description:This study found no association of the top two associated FER variants with severity of community-acquired pneumonia. Precise characterisation of phenotypes may be required in order to unravel the genetic mechanisms predisposing to poor outcome in sepsis. https://bit.ly/3jc9SmR.
Project description:Community-acquired pneumonia (CAP) remains the leading cause of hospitalization among infectious disease in Europe, and a major cause of morbidity and mortality. In order to determine and characterize the aetiology of CAP in hospitalized adults in Cyprus, respiratory and blood samples were obtained from hospitalized patients with CAP, and analyzed using Multiplex Real-Time PCR/RT-PCR, and ID/AMR enrichment panel (RPIP) analysis. Probe-based allelic discrimination was used to investigate genetic host factors in patients. The aetiology could be established in 87% of patients. The most prevalent viral pathogens detected were influenza A, SARS-CoV-2, and human rhinovirus. The most common bacterial pathogens detected were Streptococcus pneumoniae, Staphylococcus aureus, and Haemophilus influenzae. Antimicrobial resistance genes were identified in 23 patients. S. aureus was the most common AMR correlated strain in our study. A positive correlation was detected between bacterial infections and the NOS3 rs1799983 G allele and the FCGR2A rs1801274 G allele. A positive correlation was also detected between the TNF-α rs1800629 A allele and sepsis, while a negative correlation was detected with the ACE rs1799752 insertion genotype and the severity of pneumonia. In conclusion, the targeted NGS panel approach applied provides highly sensitive, comprehensive pathogen detection, in combination with antimicrobial resistance AMR insights that can guide treatment choices. In addition, several host factors have been identified that impact the disease progression and outcome.
Project description:To evaluate the impact of influenza C (ICV) infection in children with community-acquired pneumonia (CAP), all of the children consecutively seen during 4 influenza seasons with respiratory symptoms and radiographically confirmed CAP were prospectively evaluated. ICV was identified in the respiratory secretions of five of 391 patients (1·3%). In children with ICV-associated CAP, clinical data were similar to those observed in children with IAV-associated CAP and worse than those observed in children with IBV-associated. The phylogenetic tree showed that the sequenced strains clustered in two of the six ICV lineages. These findings highlight that ICV can be a cause of CAP of children and that this can be severe enough to require hospitalization.