title: Procalcitonin levels in community-acquired pneumonia - correlation with aetiology and severity.
abstract: We studied procalcitonin (PCT) levels at hospital admittance and their association with aetiology and severity in patients with community-acquired pneumonia (CAP). Median PCT concentrations were higher in bacteraemic patients than in those without bacteraemia (6.11 μg/L vs 0.34 μg/L, p = 0.0002), in patients with non-bacteraemic pneumococcal aetiology than in those infected with other classic bacteria (1.18 vs 0.18, p = 0.038), and in patients with pneumococcal as compared with viral aetiology (2.43 vs 0.24, p = 0.017). When aetiology, bacteraemia and severity according to the pneumonia severity index (PSI) were included in logistic regression analyses with PCT > 0.5 as a dependent variable, the odds ratio (OR) for non-bacteraemic pneumococcal aetiology was 5.7 (p = 0.008) and 3.0 ( p = 0.1) for PSI 4-5. A separate analysis for bacteraemia and PSI 4-5 showed an OR of 17.5 (p = 0.008) and 2.7 (p = 0.092), respectively. In CAP patients, high PCT seems to be a good marker for invasive disease and pneumococcal aetiology. As a predictor of severity it appears to be less important.
authors.affiliation: Karolinska Institutet, Department of Medicine, Solna, Infectious Diseases Unit, Karolinska University Hospital , Stockholm.
authors.forename: Niclas
authors.initials: N
authors.lastname: Johansson
authors.forename: Mats
authors.initials: M
authors.lastname: Kalin
authors.forename: Carolina
authors.initials: C
authors.lastname: Backman-Johansson
authors.forename: Anders
authors.initials: A
authors.lastname: Larsson
authors.forename: Kristina
authors.initials: K
authors.lastname: Nilsson
authors.forename: Jonas
authors.initials: J
authors.lastname: Hedlund
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016470:Bacteremia / Q000097:blood / Q000382:microbiology; D001419:Bacteria / Q000302:isolation & purification; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism; D002116:Calcitonin / Q000097:blood*; D015740:Calcitonin Gene-Related Peptide; D017714:Community-Acquired Infections / Q000097:blood* / Q000382:microbiology; D005260:Female; D006801:Humans; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D018410:Pneumonia, Bacterial / Q000097:blood* / Q000382:microbiology; D011446:Prospective Studies; D011498:Protein Precursors / Q000097:blood*; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; C000606589:CALCA protein, human; D011498:Protein Precursors; D002116:Calcitonin; D002097:C-Reactive Protein; D015740:Calcitonin Gene-Related Peptide
keywords: Bacterial pneumonia; C-reactive protein; pneumonia severity index; procalcitonin; viral