Midregional pro-atrial natriuretic peptide as a prognostic marker in pneumonia

Objective: To evaluate the usefulness of midregional pro-atrial natriuretic peptide (MR-proANP) measurement in the stratification of severity in community-acquired pneumonia. Methods: The population studied was three hundred patients admitted to Emergency Department of a tertiary university hospital presenting clinical signs of lower respiratory tract infection, a new infiltrate on the chest radiograph and a confirmed pneumonia by clinical evolution. Patients were stratified by the Pneumonia Severity Index (PSI), by CURB-65 score and by the development of complications. Serum samples were obtained at the moment of admission and prior to antibiotic therapy, and stored until analysis. MR-proANP was measured by B · R · A · H · M · S MR-proANP KRYPTOR. Results: Serum levels of MR-proANP increased with the severity of pneumonia, according to PSI score and CURB-65 score. Median MR-proANP levels were significantly higher (p < 0.0001) in patients with high PSI risk class (IV-V) than in those with low PSI risk class (I-III). MR-proANP levels were also significantly higher (p = 0.029) in those patients that developed complications or died. There was no association between MR-proANP and etiology of pneumonia and the radiographic extent. Conclusion: We can conclude that MR-proANP measurement was helpful for individual risk assessment in patients with pneumonia admitted to the emergency department. © 2007 The British Infection Society.