Usefulness of procalcitonin in differentiating Candida and bacterial blood stream infections in critically ill septic patients outside the intensive care unit

Abstract

We aimed to explore the role of procalcitonin (PCT) for the diagnosis of Candida spp. bloodstream infections in a population of critically ill septic patients admitted to internal medicine units. This is a retrospective case-control study considering all cases of candidemia identified in three internal medicine units, from January 1st 2012 to May 31st 2016. For each case of candidemia, two patients with bacteremic sepsis were included in the study as control cases. The end point of the study was to evaluate the diagnostic performance of PCT for the diagnosis of Candida spp. blood stream infections in patients with objectively documented sepsis. Sixty-four patients with candidemia and 128 controls with bacteremia were enrolled. Median and interquartile range (IQR) PCT values are significantly lower in patients with candidemia (0.73; IQR 0.26-1.85 ng/mL) than in those with bacteremia (4.48; IQR 1.10-18.26 ng/mL). At ROC curve analysis, values of PCT greater than 2.5 ng/mL had a negative predictive value (NPV) of 98.3% with an AUC of 0.76 (0.68-0.84 95% CI) for the identification of Candida spp. from blood cultures. At multivariate analysis, a PCT value\2.5 ng/mL showed an odds ratio of 8.57 (95% CI 3.09-23.70; p \ 0.0001) for candidemia. In septic patients at risk of Candida infection, a PCT value lower than 2.5 ng/mL should raise the suspicion of candidemia, adding value for considering prompt initiation of antifungal therapy.

Ability of serum procalcitonin to distinguish focus of infection and pathogen types in patients with bloodstream infection

“…Our study confirmed that the PCT median value of bacteremia patients with Gramnegative bacteria infection was significantly higher than that of Gram-positive bacteria infection. These findings are consistent with the previously published literature (1,10,11). But because the specificity was only 27%, the 0.581 of area under the curve was unsatisfactory and could not guide clinical diagnosis and treatment, which was in consistent with conclusions from Thomas-Rüddel et al (13).…”

“…Recent studies showed that PCT was a promising inflammatory marker, which can distinguish systemic bacterial infection from other types of infections, judge the severity of bacterial infection, estimate the therapeutic effect and prognosis of BSI, and guide the use of antibiotics (6)(7)(8)(9). Some recent studies have further found that PCT can distinguish different types of pathogenic bacteria on the basis of Gram staining in patients with BSI (1,10,11), providing rapid support for the preliminary selection of antibiotics. However, other studies did not show these findings (12,13).…”

Procalcitonin-guided antibiotic therapy: an expert consensus

“…However, different real-life experiences in patients with intra-abdominal infection and in ICU patients with bloodstream infection suggest that higher cutoff should be considered in these settings [32,37]. In this latter case, higher cutoff values may be helpful to differentiate between bacterial and fungal infections [46,47]. It is worth noting that all the available literature was produced using the high sensitive assays based on B…”

Kinetics of Procalcitonin in Pediatric Patients on Extracorporeal Membrane Oxygenation

“…Although there is little evidence, it appears that PCT minimally increases in the presence of fungal infection. 27 …”