Plasma Neprilysin for Predicting Sepsis Within 48 Hours in ICU Patients With Infection or Suspected Infection

The goal of this multicenter prospective observational cohort study is to determine whether plasma neprilysin can predict the development of sepsis within 48 hours in adults admitted to an intensive care unit with confirmed or suspected infection who do not have sepsis at enrollment. The study will be conducted at Zhujiang Hospital, Southern Medical University, and Guangzhou First Municipal People\'s Hospital. Plasma samples remaining after routine clinical testing will be used to measure neprilysin and conventional sepsis biomarkers. Sublingual microcirculation will also be assessed when feasible. Participants will be assessed for the development of sepsis from enrollment through 48 hours and will be followed for survival through Day 28. No treatment or clinical intervention will be assigned by the study protocol.