title: Predictive value of procalcitonin decrease in patients with severe sepsis: a prospective observational study.
abstract: BACKGROUND
  This prospective study investigated the predictive value of procalcitonin (PCT) for survival in 242 adult patients with severe sepsis and septic shock treated in intensive care.
  
  
  METHODS
  PCT was analyzed from blood samples of all patients at baseline, and 155 patients 72 hours later.
  
  
  RESULTS
  The median PCT serum concentration on day 0 was 5.0 ng/ml (interquartile range (IQR) 1.0 and 20.1 ng/ml) and 1.3 ng/ml (IQR 0.5 and 5.8 ng/ml) 72 hours later. Hospital mortality was 25.6% (62/242). Median PCT concentrations in patients with community-acquired infections were higher than with nosocomial infections (P = 0.001). Blood cultures were positive in 28.5% of patients (n = 69), and severe sepsis with positive blood cultures was associated with higher PCT levels than with negative cultures (P = < 0.001). Patients with septic shock had higher PCT concentrations than patients without (P = 0.02). PCT concentrations did not differ between hospital survivors and nonsurvivors (P = 0.64 and P = 0.99, respectively), but mortality was lower in patients whose PCT concentration decreased > 50% (by 72 hours) compared to those with a < 50% decrease (12.2% vs. 29.8%, P = 0.007).
  
  
  CONCLUSIONS
  PCT concentrations were higher in more severe forms of severe sepsis, but a substantial concentration decrease was more important for survival than absolute values.
authors.affiliation: Department of Intensive Care Medicine, Tampere University Hospital, Teiskontie 35, 33521 Tampere, Finland. sari.karlsson@pshp.fi
authors.forename: Sari
authors.initials: S
authors.lastname: Karlsson
authors.forename: Milja
authors.initials: M
authors.lastname: Heikkinen
authors.forename: Ville
authors.initials: V
authors.lastname: Pettilä
authors.forename: Seija
authors.initials: S
authors.lastname: Alila
authors.forename: Sari
authors.initials: S
authors.lastname: Väisänen
authors.forename: Kari
authors.initials: K
authors.lastname: Pulkki
authors.forename: Elina
authors.initials: E
authors.lastname: Kolho
authors.forename: Esko
authors.initials: E
authors.lastname: Ruokonen
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D002116:Calcitonin / Q000037:antagonists & inhibitors* / Q000097:blood; D015740:Calcitonin Gene-Related Peptide; D015331:Cohort Studies; D005260:Female; D017052:Hospital Mortality / Q000639:trends; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011498:Protein Precursors / Q000037:antagonists & inhibitors* / Q000097:blood; D018805:Sepsis / Q000097:blood* / Q000175:diagnosis* / Q000401:mortality; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; C000606589:CALCA protein, human; D011498:Protein Precursors; D002116:Calcitonin; D015740:Calcitonin Gene-Related Peptide