CSF3 and viral infectious disease: G-CSF demonstrated AUC = 0.763 for distinguishing infectious from non-infectious episodes, while IP-10 showed AUC = 0.702 specifically for viral infection detection, both validated in persistent high-risk febrile neutropenia (Tapia 2021 [6]) In contrast, sIL-2R displays only moderate performance (AUC 0.73; Urbonas 2013 [22]), contradicting earlier claims of Gram-negative specificity (Soker 2001 [18]).