Table 1: Summary of the studies in critically ill patients.

StudiesTypes of patients includedConclusionsRemarks

Ugarte et al. [18]180 patients with
and without infections .
Best cut-off value
for CRP levels for diagnosis of infection was 7.9 mg/dL
Exclusion of surgical patients

Reny et al. [19]74 patients with 28 with proven infection Higher CRP concentrations in infected patients
(i) No cut-off value for CRP
(ii) Evolution of CRP between admission and day 4 was related to outcome

Póvoa et al. [20]Subgroup of patients with VAP Higher CRP levels in patients with VAP than in noninfected patients. No CRP comparisons between patients with VAP and other infections

Póvoa et al. [21]Patients with a length of stay ≥3 daysA maximum daily variation of 4.1 mg/dL is a good marker of infection Long delay between positive culture and start of antibiotics

Lobo et al. [22]303 patients with a length of stay ≥2 days(i) High CRP at admission was associated with higher risk of infection
(ii) Daily increase in CRP was associated with mortality
Results only applicable if CRP at admission is >10 mg/dL

Castelli et al. [23]255 patients (111 septic, 49 trauma, 45 with, and 50 without SIRS)(i) Cut-off for infection: 128 mg/L
(ii) Higher values in relation to the severity of sepsis
Maximum CRP with a delay of 24 or 48 hours

Silvestre et al. [24]158 ICU patientsNo relationship between CRP at ICU admission and infection and mortalityNo relationship between CRP and presence of a microorganism

Póvoa et al. [25]891 patients admitted in ICU with diagnosis of community-acquired sepsis.
Follow-up of 5 days
(i) No difference in CRP at ICU admission between survivors or nonsurvivors
(ii) No decrease in CRP at day 3 was associated with a poor outcome
Same evolution for SOFA score but not for fever or leukocyte count

Vandijck et al. [26]84 ICU patients with nosocomial bacteremiaHigher values of CRP with Gram-negative bacilli compared to Gram-positive cocci bacteremiaReview of the time course of CRP before the bacteremia
Predictive factor?

Póvoa et al. [27] 44 ICU patients with bacteremia
CRP concentrations ratio start to change only at day 2 in survivors. CRP ratio only predictive of outcome at day 4

Zhang and Ni [28]Meta-analysis of 14 studies including 1969 patients Evolution of CRP for more than 48 hours is predictive of outcomeLarge heterogeneity of the studies ( = 92%)

Póvoa et al. [29]186 septic cancer patients with or without neutropenia(i) CRP concentrations were higher in neutropenic patients
(ii) No relation with the severity of the neutropenia
Same evolution of CRP between neutropenic and nonneutropenic patients

Fraunberger et al. [30]38 ICU patients at the onset of fever(i) Increase in CRP at the onset of fever
(ii) No difference between survivors and nonsurvivors
Comparisons of CRP between ICU patients and volunteers

Su et al. [31]144 ICU patients at the onset of fever (84 sepsis and 64 SIRS)(i) CRP more elevated in septic compared to patients with SIRS
(ii) CRP increase at the onset of fever and could discriminate patients with or without bacteremia
CRP concentrations were lower in patients with bacteremia

Christ-Crain et al. [32]50 infected patients with or without appropriate antibiotics or peritonitis An increase in CRP of at least 2.2 mg/dL in the first 48 h was associated with ineffective initial antibiotic therapy(i) Only 8 patients with peritonitis
(ii) No data on the timing of reintervention

Bota et al. [33]864 patients with and without cirrhosis (i) CRP levels were higher in cirrhotic with infection compared to cirrhotic patients without infection.
(ii) No difference related to severity of the cirrhosis assessed
by the Child-Pugh classification.
No data about CRP levels in relation with the severity of sepsis (SOFA, vasopressor dosage, PaO2/FiO2, extra renal replacement) for each level of cirrhosis

Silvestre et al. [34]7 patients with hepatic failure Low CRP levels in patients with infection Few patients included. One with a diagnosis of hepatic failure at ICU day 26