Dynamic Pattern of Etiology, Immunoinflammatory Factors and Their Association With Prognosis of Severe Pneumonia

The goal of this longitudinal observational study is to investigate the pathogen spectrum composition of severe pneumonia (SP) in different disease stages and to study the changes of immune inflammatory factors in patients with SP in different course of disease during and after the COVID-19 pandemic. The main questions it aims to answer is: What is the pathogenic profile of SP patient admitted in intensive care unit (ICU) during and after COVID-19 pandemic? What is the dynamic pattern of etiology and immunoinflammatory factors of SP progression during the period in ICU? Are those indexes mentioned above associated with the prognosis of SP?