Diagnosis and follow-up of infections in intensive care patients: value of C-reactive protein compared with other clinical and biological variables.
OBJECTIVE
To evaluate diagnostic and prognostic values of C-reactive protein (CRP) dosage in critically ill patients.


METHODS
Prospective, observational study.


METHODS
Medical intensive care unit (ICU) in a university hospital.


METHODS
A consecutive series of 74 patients admitted to the ICU.


METHODS
CRP measurements at admission and every 4 days thereafter.


RESULTS
At admission, 28 patients (38%) had microbiologically proven infections. Compared with uninfected patients, their mean +/- SD CRP level was 191 +/- 123 vs. 83 +/- 91 mg/L (p < .0001), respectively, white blood cell count was 15.3 +/- 7.5 vs. 11.4 +/- 5.3 G/L (p = .01), and the systemic inflammatory response syndrome (SIRS) was present for 96% vs. 67% (p = .008). No threshold value could be identified to discriminate between these two populations. Multivariate analysis retained CRP and SIRS as the only variables independently associated with the presence of an infection. The combination of CRP > or = 50 mg/L with SIRS was identified as the best model to diagnose infection at admission. This multivariate model performed better than temperature, CRP alone, and white blood cell count. Among the 28 infected patients, 10 recovered; CRP values decreased significantly in this population as compared with patients with persistent infection (-130 +/- 110 vs. 12 +/- 97 mg/L, respectively; p = .004). A CRP decrease > or = 50 mg/L between admission and day 4 was the best cutoff value to diagnose recovery (sensitivity 89%, specificity 79%).


CONCLUSIONS
CRP in combination with SIRS was useful to diagnose infection in ICU patients; a CRP decrease > or = 50 mg/L between admission and day 4 was the best predictor of recovery.
Reny
Jean-Luc
JL
Service de Réanimation Médicale, Hôpital Broussais, Paris, France.
Vuagnat
Albert
A
Ract
Catherine
C
Benoit
Marie-Odile
MO
Safar
Michel
M
Fagon
Jean-Yves
JY
D015415:Biomarkers; D002097:C-Reactive Protein / Q000378:metabolism*; D005260:Female; D006801:Humans; D007239:Infections / Q000150:complications / Q000175:diagnosis*; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D011446:Prospective Studies; D012372:ROC Curve; D012680:Sensitivity and Specificity; D018746:Systemic Inflammatory Response Syndrome / Q000382:microbiology
D015415:Biomarkers; D002097:C-Reactive Protein