Among these differentially expressed iron metabolism-related genes, LCN2 is the only gene that showed significant difference simultaneously in all the comparisons including sepsis vs healthy controls, sepsis vs non-infection disease, sepsis vs uncomplicated infections, sepsis shock vs sepsis, severe sepsis vs mild sepsis, and also in the comparisons of deceased vs survived group of sepsis, suggesting its expression has a high diagnostic value for sepsis and also for the severe forms of sepsis like sepsis shock. Here, LCN2 is linked to infection.