Personalized medicine in severe influenza.

Existing therapies against infectious diseases may only be effective in limited subpopulations during specific phases of diseases, incorporating theranostics, and there is a clear need to individualize different therapeutic approaches depending on the host. Influenza A virus infection evolves into a severe respiratory failure in some young adult patients, related to an exaggerated inflammatory response. Mortality rates remain high despite antiviral treatment and aggressive respiratory support. The influenza A virus (IAV) infection will induce a proinflammatory innate immune response through recognition of viral RNA by Toll-like receptor (TLR) 7 and retinoic acid-inducible gene 1 (RIG-I) molecules by nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB route). Anti-inflammatory therapies focused on modulating this inflammatory response to "all patients" have not been satisfactory. Steroids should be avoided because they do not improve survival and promote superinfections. Since clinical judgment has often been proven inadequate, interest in the use of biomarkers to monitor host response and to assess severity and complications is growing. It is well known that, if used appropriately, these can be helpful tools to predict not only severity but also mortality. We need more biomarkers that predict host response: it is time to change lactate measurement to proteomics and transcriptomics. Theranostics describes an approach covering both diagnosis and coupled therapy. Death is usually a fatal complication of a dysregulated immune response more than the acute virulence of the infectious agent. Future research demonstrating the usefulness of adjunctive therapy in a subset of critically ill patients with IAV pneumonia is an unmet clinical need.