title: C-reactive protein used as an early indicator of infection in patients with systemic inflammatory response syndrome.
abstract: OBJECTIVE
  To assess the diagnostic value of a single determination of serum C-reactive protein as a marker of sepsis in critically ill patients.
  
  
  METHODS
  Prospective, observational study.
  
  
  METHODS
  Intensive care unit of a university hospital.
  
  
  METHODS
  One hundred twenty-five adult patients with systemic inflammatory response syndrome (SIRS) (55 patients without evidence of infection and 70 patients with the diagnosis of sepsis confirmed by documented infection). Twenty-five patients with non-complicated acute myocardial infarctions (AMI) and 50 healthy volunteers were used as controls.
  
  
  METHODS
  None.
  
  
  RESULTS
  Serum C-reactive protein concentration was measured within the first 24 h of SIRS onset. Healthy subjects, AMI and non-infectious SIRS patients showed lower C-reactive protein median values ([(0.21 [95% confidence intervals (95% CI), 0.21-0.4] mg/dl, 2.2 [95% CI, 2.1-4.9] mg/dl and 1.7 [95% CI, 2.4-5.5] mg/dl, respectively) than patients with sepsis (18.9 [95% CI, 17.1-21.8]), p<0.001. The presence of severe sepsis ( r(s)=0.27; p=0.03), SOFA score ( r(s)=0.25; p=0.03) and arterial lactate ( r(s)=0.24; p=0.04) correlated significantly with C-reactive protein concentrations in sepsis cases. The best threshold value for C-reactive protein for predicting sepsis was 8 mg/dl (sensitivity 94.3%, specificity 87.3%). The area under the receiver-operating characteristic curve for C-reactive protein was 0.94 (95% CI, 0.89-0.98).
  
  
  CONCLUSIONS
  Determination of serum C-reactive protein can be used as an early indicator of infection in patients with SIRS.
authors.affiliation: Intensive Care Unit, Puerta del Mar University Hospital, Cádiz, Spain. rsc@comcadiz.com
authors.forename: Rafael
authors.initials: R
authors.lastname: Sierra
authors.forename: Jordi
authors.initials: J
authors.lastname: Rello
authors.forename: María Angeles
authors.initials: MA
authors.lastname: Bailén
authors.forename: Encarnación
authors.initials: E
authors.lastname: Benítez
authors.forename: Antonio
authors.initials: A
authors.lastname: Gordillo
authors.forename: Cristobal
authors.initials: C
authors.lastname: León
authors.forename: Sebastián
authors.initials: S
authors.lastname: Pedraza
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001424:Bacterial Infections / Q000150:complications / Q000175:diagnosis*; D015415:Biomarkers; D002097:C-Reactive Protein / Q000378:metabolism*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D016013:Likelihood Functions; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D018746:Systemic Inflammatory Response Syndrome / Q000175:diagnosis* / Q000382:microbiology
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein