CST3 and thrombophilia: As illustrated in Figure 2, fatal patients at stage B demonstrated the following notable features: (1) significantly higher levels of viral load, AST, interleukin-6 (IL-6), LDH, HSTNI, BUN, creatinine, and cystatin C, further underscoring the prevalence of multi-organ damage in severe cases (Figure 2a–i), and (2) prolonged activated partial thromboplastin time (APTT) and thrombin time (TT), as well as increased D-dimer (DD) concentrations, suggesting activation of the coagulation system and a hypercoagulable state during the progressive phase (Figure 2j–l).