title: Diagnostic and prognostic value of procalcitonin among febrile critically ill patients with prolonged ICU stay.
abstract: BACKGROUND
  Procalcitonin (PCT) has been proposed as a diagnostic and prognostic sepsis marker, but has never been validated in febrile patients with prolonged ICU stay.
  
  
  METHODS
  Patients were included in the study provided they were hospitalised in the ICU for > 10 days, were free of infection and presented a new episode of SIRS, with fever >38 degrees C being obligatory. Fifty patients fulfilled the above criteria. PCT was measured daily during the ICU stay. The primary outcome was proven infection.
  
  
  RESULTS
  Twenty-seven out of 50 patients were diagnosed with infection. Median PCT on the day of fever was 1.18 and 0.17 ng/ml for patients with and without proven infections (p < 0.001). The area under the curve for PCT was 0.85 (95% CI; 0.71-0.93), for CRP 0.65 (0.46-0.78) and for WBC 0.68 (0.49-0.81). A PCT level of 1 ng/mL yielded a negative predictive value of 72% for the presence of infection, while a PCT of 1.16 had a specificity of 100%. A two-fold increase of PCT between fever onset and the previous day was associated with proven infection (p 0.001) (OR = 8.55; 2.4-31.1), whereas a four-fold increase of PCT of any of the 6 preceding days was associated with a positive predictive value exceeding 69.65%. A PCT value less than 0.5 ng/ml on the third day after the advent of fever was associated with favorable survival (p 0.01).
  
  
  CONCLUSIONS
  The reported data support that serial serum PCT may be a valuable diagnostic and prognostic marker in febrile chronic critically ill patients.
authors.affiliation: The 2nd Critical Care Department, Attikon University General Hospital, Medical School, University of Athens, 1 Rimini Str,, 12462, Athens, Greece. itsagkaris@med.uoa.gr
authors.forename: Iraklis
authors.initials: I
authors.lastname: Tsangaris
authors.forename: Diamantis
authors.initials: D
authors.lastname: Plachouras
authors.forename: Dimitra
authors.initials: D
authors.lastname: Kavatha
authors.forename: George Michael
authors.initials: GM
authors.lastname: Gourgoulis
authors.forename: Argirios
authors.initials: A
authors.lastname: Tsantes
authors.forename: Petros
authors.initials: P
authors.lastname: Kopterides
authors.forename: George
authors.initials: G
authors.lastname: Tsaknis
authors.forename: Ioanna
authors.initials: I
authors.lastname: Dimopoulou
authors.forename: Stylianos
authors.initials: S
authors.lastname: Orfanos
authors.forename: Evangelos
authors.initials: E
authors.lastname: Giamarellos-Bourboulis
authors.forename: Helen
authors.initials: H
authors.lastname: Giamarellou
authors.forename: Apostolos
authors.initials: A
authors.lastname: Armaganidis
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019540:Area Under Curve; D001424:Bacterial Infections / Q000097:blood / Q000175:diagnosis; D015415:Biomarkers / Q000097:blood*; D002116:Calcitonin / Q000097:blood*; D015740:Calcitonin Gene-Related Peptide; D016638:Critical Illness; D005260:Female; D005334:Fever / Q000097:blood*; D006801:Humans; D007362:Intensive Care Units; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011498:Protein Precursors / Q000097:blood*; D012680:Sensitivity and Specificity; D018746:Systemic Inflammatory Response Syndrome / Q000097:blood* / Q000175:diagnosis
chemical_list: D015415:Biomarkers; C000606589:CALCA protein, human; D011498:Protein Precursors; D002116:Calcitonin; D015740:Calcitonin Gene-Related Peptide