The diagnostic accuracy of procalcitonin for bacteraemia: a systematic review and meta-analysis

Abstract

The diagnostic use of procalcitonin for bacterial infections remains a matter of debate. Most studies have used ambiguous outcome measures such as sepsis instead of infection. We performed a systematic review and meta-analysis to investigate the diagnostic accuracy of procalcitonin for bacteraemia, a proven bloodstream infection. We searched all major databases from inception to June 2014 for original, English language, research articles that studied the diagnostic accuracy between procalcitonin and positive blood cultures in adult patients. We calculated the area under the summary receiver-operating characteristic (SROC) curves and pooled sensitivities and specificities. To minimize potential heterogeneity we performed subgroup analyses. In total, 58 of 1567 eligible studies were included in the meta-analysis and provided a total of 16,514 patients, of whom 3420 suffered from bacteraemia. In the overall analysis the area under the SROC curve was 0.79. The optimal and most widely used procalcitonin cut-off value was 0.5 ng/mL with a corresponding sensitivity of 76% and specificity of 69%. In subgroup analyses the lowest area under the SROC curve was found in immunocompromised/neutropenic patients (0.71), the highest area under the SROC curve was found in intensive-care patients (0.88), sensitivities ranging from 66 to 89% and specificities from 55 78%. In spite of study heterogeneity, procalcitonin had a fair diagnostic accuracy for bacteraemia in adult patients suspected of infection or sepsis. In particular low procalcitonin levels can be used to rule out the presence of bacteraemia. Further research is needed on the safety and efficacy of procalcitonin as a single diagnostic tool to avoid taking blood cultures.

Diagnostic accuracy of presepsin (sCD14-ST) and procalcitonin for prediction of bacteraemia and bacterial DNAaemia in patients with suspected sepsis

“…Nevertheless, the results of this study are in line with those of a large observational study on 35 343 consecutive patients, in which PCT was highly effective excluding bloodstream infections regardless of pathogen categories, with the highest PCT concentration observed in patients with BCs growing Gram-negative bacteria (Oussalah et al, 2015). Likewise, in a recent systematic review and meta-analysis on 16 514 patients, an AUC of 0.79 was found for PCT in predicting bacteraemia (Hoeboer et al, 2015). Moreover, PCT AUCs found in this study match our previous results Leli et al, 2014), highlighting its accuracy in identifying not only bacteraemia but also bacterial DNAaemia.…”

Can procalcitonin levels indicate the need for adjunctive therapies in sepsis?

“…Owing to the non-specific properties of conventional signs of infection, such as body temperature and white blood cell count, for decades biomarkers have been searched for to aid diagnosis. One of the most studied biomarkers of the last decade is procalcitonin (PCT) [7]. Its role in assisting antibiotic therapy has been studied extensively [8,9], but it may also have a potential role in guiding adjunctive therapies in the critically ill. Modulation of the immune system and the host's response has also been the focus of research interest.…”

Procalcitonin as a Biomarker for Infection and Sepsis: Yet Again

“…Analytic methods reflected year of publication, with the earlier studies [16][17][18][19] using the linear regression model of Moses et al, as opposed to the mixed-effects bivariate approach of the two more recent studies [11,14]; a point of importance for Wacker and co-authors [14]. Overall, the diagnostic performance could at best be described as modest, a point conceded by some of the authors [11,16,18] and reiterated by Afshari and Harbath [22], commenting upon the somewhat fulsome conclusions of Wacker et al [14]. The former noted that the sensitivity of 77% corresponded to 23% of patients not receiving adequate therapy and a specificity of 79% corresponded to 21% being unnecessarily treated (Table 1); similarly, a positive likelihood ratio of 3.67 and a negative likelihood ratio of 0.29, being small and containing no information, were "… of little use for guiding initial treatment decisions", especially in the critically ill with a high pre-test sepsis probability [22].…”

“…We first summarize certain key parameters of procalcitonin performance as a diagnostic biomarker in 6 meta-analyses, conducted between the years of 2004-2015; author sub-group analyses are not considered (Table 1) [11,14,[16][17][18][19]. Where reported, heterogeneity was a marked feature, even when restricted to a more circumscribed population of the "critically ill"; the components of heterogeneity presumably reflecting such factors as different procalcitonin assays and threshold levels, patient subgroups, endpoint prevalence, primary study inclusions and exclusions, and study quality / bias [5].…”

“…Procalcitonin qualifies as both a diagnostic (an infection or sepsis marker) and predictive (a guide to antimicrobial therapy) biomarker. This being said, procalcitonin biomarker performance has been subjected to a large number of meta-analyses [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20], suggesting a degree of disquiet regarding the actual level of evidence for procalcitonin utility.We first summarize certain key parameters of procalcitonin performance as a diagnostic biomarker in 6 meta-analyses, conducted between the years of 2004-2015; author sub-group analyses are not considered (Table 1) [11,14,[16][17][18][19]. Where reported, heterogeneity was a marked feature, even when restricted to a more circumscribed population of the "critically ill"; the components of heterogeneity presumably reflecting such factors as different procalcitonin assays and threshold levels, patient subgroups, endpoint prevalence, primary study inclusions and exclusions, and study quality / bias [5].…”