Pro-adrenomedullin, procalcitonin and CRP levels to predict bacterial pneumonia in patients admitted to emergency room

Objectives: To assess if MR-proADM, PCT and CRP levels can distinguish bacterial pneumonia from other kind of lower respiratory tract infections (LRTI). Methods: Patients with fever and respiratory symptoms that were admitted in emergency room (ER) and from whom blood cultures were drawn. After retrospective analysis, patients were classified as: pneumonia (n=85), chronic obstructive pulmonary disease (COPD) exacerbation (n=25) and bronchial infection (n=52). Four patients were admitted to ICU and 9 died. Results: PCT showed significantly higher levels in pneumonia when comparing with COPD exacerbation (p=0.003) and bronchial infection (p=0.002). CRP only showed significantly higher levels when comparing pneumonia group vs bronchial infection (p=0.002). Finally, MR-proADM showed statistical higher levels when comparing pneumonia group with COPD exacerbation (p=0.014) and bronchial infection (p=0.006). PCT and MR-proADM showed significantly higher levels in cases of definite bacterial diagnosis in comparison to other cases (pneumonia of probable bacterial or unknown origin, COPD exacerbations and bronchial infections) (p=0.017 and p=0.004). PCT and MR-proADM are significantly higher in patients admitted to ICU (p=0.011 and p=0.001). Regarding mortality, no significant differences were found. Conclusions: PCT and MR-proADM show significantly higher levels in pneumonia in comparison to other lower respiratory tract infections. PCT and MR-proADM levels are increased in confirmed bacterial infections. Biomarkers measurement can be helpful for the management of patients admitted in ER with clinical symptoms of respiratory tract infection.