Serial Procalcitonin as a Predictor of Bacteremia and Need for Intensive Care Unit Care in Adults With Pneumonia, Including Those With Highest Severity: A Prospective Cohort Study

Abstract

Background.Procalcitonin (PCT) is a prohormone that rises in bacterial pneumonia and has promise in reducing antibiotic use. Despite these attributes, there are inconclusive data on its use for clinical prognostication. We hypothesize that serial PCT measurements can predict mortality, intensive care unit (ICU) admission, and bacteremia.Methods.A prospective cohort study of inpatients diagnosed with pneumonia was performed at a large tertiary care center in Boston, Massachusetts. Procalcitonin was measured on days 1 through 4. The primary endpoint was a composite adverse outcome defined as all-cause mortality, ICU admission, and bacteremia. Regression models were calculated with area under the receiver operating characteristic curve (AUC) as a measure of discrimination.Results.Of 505 patients, 317 patients had a final diagnosis of community-acquired pneumonia (CAP) or healthcare-associated pneumonia (HCAP). Procalcitonin was significantly higher for CAP and HCAP patients meeting the composite primary endpoint, bacteremia, and ICU admission, but not mortality. Incorporation of serial PCT levels into a statistical model including the Pneumonia Severity Index (PSI) improved the prognostic performance of the PSI with respect to the primary composite endpoint (AUC from 0.61 to 0.66), bacteremia (AUC from 0.67 to 0.85), and need for ICU-level care (AUC from 0.58 to 0.64). For patients in the highest risk class PSI >130, PCT was capable of further risk stratification for prediction of adverse outcomes.Conclusion.Serial PCT measurement in patients with pneumonia shows promise for predicting adverse clinical outcomes, including in those at highest mortality risk.

Procalcitonin is not an independent predictor of 30-day mortality, albeit predicts pneumonia severity in patients with pneumonia acquired outside the hospital

“…Though many investigators have studied the utility of PCT in predicting mortality in various types of pneumonia including CAP [5–7, 17–26], HCAP [37, 38], VAP [39–43] and HAP [44], their results were not consistent While some reported PCT to be a reliable predictor for mortality [17–26], others showed that PCT was inferior to other markers such as PSI, CURB-65 [52], CRP, IL-6 [53], or BUN/albumin ratio [54] for predicting mortality. Several investigators reported that serial measurements of PCT were useful for predicting mortality [21, 50, 55]. In the present study, PCT did not remain an independent prognostic factor in the younger and elderly patients in our multivariate analysis.…”

Utility of Procalcitonin in the Management of Hospital-Acquired Pneumonia - A Review

“…The study found that for the total population at PCT values of 0.1, 0.25, and 0.5 ng/mL, sensitivity was 63%, 54%, and 46%, respectively, for the composite endpoint, all with negative predictive value >80%. The specificity of PCTbased prognosis using these cut-offs was highest when evaluating the HCAP subpopulation, whereas sensitivity was highest in the CAP group [48].…”

“…Several studies have shown PCT to be useful as a prognostic indicator in patients with pneumonia. The studies were predominantly conducted among patients with community-acquired pneumonia (CAP) [19,[36][37][38][39][40][41][42][43][44][45][46][47][48], healthcare-associated pneumonia (HCAP) [20,48,49] and HAP/VAP [31,32,[50][51][52][53][54][55][56]. In the most recently published study, Hong DY et al, [20] used PCT in HCAP patients to determine its efficacy as an indicator for predicting mortality.…”

Clinical Progress Note: Procalcitonin in the Management of Pediatric Lower Respiratory Tract Infection

“…8 In a 2017 study of 317 adults hospitalized with pneumonia, the PCT level was significantly higher in those with bacteremia and in those admitted to intensive care. 9 When used in combination with the pneumonia severity index (PSI), the ad-dition of PCT resulted in improved prognostic performance compared with the PSI alone for both outcomes, increasing the area under the receiver operating characteristic curve from 0.67 to 0.85 for bacteremia and from 0.58 to 0.64 for intensive care. Similarly, in the adult EPIC cohort, the addition of PCT contributed significant prognostic information beyond existing severity scores for predicting the need for invasive respiratory or vasopressor support; each 1 µg/L increase in PCT was associated with a 1% to 2% absolute increase in the need for this outcome.…”