All serologic tests showed poor prognostic value in predicting persisting infection, with the AUC of 61.6% (95% CI, 42.2 to 80.2%) for CRP, 57.8% (95% CI, 37.2 to 78.8%) for ESR, 60.3% (95% CI, 43.5 to 73.3%) for IL-6, and 62.1% (42.4 to 81.0%) for the combination of the three tests. Here, IL6 is linked to infection.