Severe community-acquired pneumonia: a paradigm shift toward precision diagnostics, microbiology, and targeted...

Severe community-acquired pneumonia (sCAP) remains one of the most lethal infectious syndromes in critical care, with mortality remaining persistently high despite decades of antimicrobial and supportive care advances. This review appraises recent developments in diagnostics, microbiology, and host-response biology, and advocates for a fundamental shift toward precision-driven management.

High-resolution molecular diagnostics have exposed the true complexity of sCAP, revealing a substantial viral burden and a polymicrobial ecosystem that challenges traditional pathogen-centric models. Yet, this diagnostic revolution has failed to translate into meaningful antimicrobial stewardship, reflecting a persistent disconnect between detection and decision-making. At the same time, multiomic and transcriptomic studies have redefined sCAP as a biologically heterogeneous syndrome, characterized by divergent host-response states ranging from hyperinflammation to immune dysfunction. These insights are beginning to reshape therapy, supporting phenotype-directed immunomodulation, including selective corticosteroid use and biomarker-guided interventions such as interleukin-1 blockade. In parallel, artificial intelligence and radiomics are emerging as powerful tools capable of integrating complex, multidimensional data, although their clinical utility remains largely unrealized.

sCAP should no longer be approached as a uniform infectious disease but as a spectrum of biologically distinct endotypes. The future lies in integrating pathogen detection with real-time host profiling and advanced analytics to enable truly personalized care. Without this paradigm shift, further gains in outcomes are unlikely.