NPPB and infection: The ROC curve analysis in patients with AHF and respiratory or other infection showed that the combination of NT-proBNP and PCT had a significantly higher diagnostic performance than PCT alone (AUC = 0.949 (95% CI: 0.903–0.977) for NT-proBNP + PCT vs. AUC = 0.822 (95% CI: 0.754–0.877) for PCT, p = 0.0440) (Figure 1F; Table 3).