In a cohort of 785 CAP-patients with 4.5% bacteraemic patients, the PSI score (Pneumonia Severity Index for CAP, ROC-AUC: 0.720, 95%CI: 0.630–0.809) and the CURB-65 score (Confusion, BUN > 7 mmol/l, Respiratory rate ≥30, SBP <90 mmHg, DBP ≤ 60 mmHg, Age ≥ 65, ROC-AUC: 0.720; 95%CI: 0.622–0.819) showed a better capacity for predicting bacteraemia than CRP (ROC-AUC: 0.629, 95%CI: 0.522–0.735)41. This evidence concerns the gene CRP and susceptibility to pneumonia measurement.