RecruitingClinical trialThe APS Phenotyping StudyThe goal of the observational APS phenotyping study is to better understand risk factors, potential biomarkers, length and severity of illness, and recovery for adults with ARDS, pneumonia, and/ or sepsis. This study will also generate a biobank of specimens collected from these patients that will be available to investigators for future studies of ARDS, sepsis, and/or pneumonia.