Plasma procalcitonin and C-reactive protein in acute septic shock: clinical and biological correlates.
OBJECTIVE
To determine the relationship between plasma procalcitonin (PCT) levels, C-reactive protein (CRP), white blood cell count (WBC), ionized calcium (Ca2+), and patient outcome; and to compare the diagnostic and prognostic information provided by PCT and by CRP.


METHODS
Prospective, observational study.


METHODS
Intensive care unit.


METHODS
Fifty-three patients with septic shock, consecutively diagnosed according to consensus guidelines.


METHODS
None.


RESULTS
Blood was sampled at diagnosis and 24 and 48 hrs later and in a subgroup (n = 23) after 120 hrs. PCT was measured with LUMItest and CRP with Vitros slides. Ca2+ was calculated according to McLean-Hastings from calcium and protein levels on Vitros. In all 53 patients, PCT and CRP were elevated (>0.5 ng/mL and >10 mg/L, respectively) within 24 hrs after diagnosis. Nonsurvivors (n = 25) were older (p <.001) and had higher Acute Physiology and Chronic Health Evaluation (APACHE) II scores (p =.02) at diagnosis but did not differ in sepsis etiology, medical history, sex ratio, levels of PCT, CRP, and Ca2+, or WBC count at any time point. Using logistic regression, initial PCT levels were correlated with CRP values (p =.001) and APACHE II score (p <.05), but not with age, gender, Ca2+ levels, survival, or type of pathogen. Within 48 hrs, however, PCT levels decreased more frequently from baseline in survivors than in nonsurvivors (80% vs. 41%, p <.05). Likewise, CRP levels decreased more often in survivors (100% vs. 64%, p <.05) but only at 120 hrs.


CONCLUSIONS
PCT levels were correlated with the severity of disease at onset (APACHE II) and inflammation (CRP) but not with Ca2+ levels. Inaugural PCT or CRP levels per se poorly predicted outcome but decreasing levels were associated with a higher probability of survival. In this respect, PCT was found to be an earlier marker than CRP.
Claeys
Roxane
R
Department of Clinical Chemistry, Vrije Universiteit Brussels, Brussels, Belgium.
Vinken
Stephanie
S
Spapen
Herbert
H
ver Elst
Kristien
K
Decochez
Katelyn
K
Huyghens
Luc
L
Gorus
Frans K
FK
D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000032:analysis*; D002116:Calcitonin / Q000097:blood*; D015740:Calcitonin Gene-Related Peptide; D002118:Calcium / Q000097:blood; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D011498:Protein Precursors / Q000097:blood*; D012772:Shock, Septic / Q000097:blood* / Q000401:mortality
D015415:Biomarkers; C000606589:CALCA protein, human; D011498:Protein Precursors; D002116:Calcitonin; D002097:C-Reactive Protein; D015740:Calcitonin Gene-Related Peptide; D002118:Calcium