Bacterial pneumonia-induced shedding of epithelial heparan sulfate inhibits the bactericidal activity of cathelicidin in a murine model.

Bacterial pneumonia is a common clinical syndrome leading to significant morbidity and mortality worldwide. In the current study, we investigate a novel, multidirectional relationship between the pulmonary epithelial glycocalyx and antimicrobial peptides in the setting of methicillin-resistant (MRSA) pneumonia. Using an in vivo pneumonia model, we demonstrate that highly sulfated heparan sulfate (HS) oligosaccharides are shed into the airspaces in response to MRSA pneumonia.

Hospital trajectories and early predictors of clinical outcomes differ between SARS-CoV-2 and influenza pneumonia.

Background: A comparison of pneumonias due to SARS-CoV-2 and influenza, in terms of clinical course and predictors of outcomes, might inform prognosis and resource management. We aimed to compare clinical course and outcome predictors in SARS-CoV-2 and influenza pneumonia using multi-state modelling and supervised machine learning on clinical data among hospitalised patients.

Methods: This multicenter retrospective cohort study of patients hospitalised with SARS-CoV-2 (March-December 2020) or influenza (Jan 2015-March 2020) pneumonia had the composite of hospital mortality and hospice discharge as the primary outcome.