Infectious disease/original researchProcalcitonin Test in the Diagnosis of Bacteremia: A Meta-analysis
Introduction
Procalcitonin is a prohormone of calcitonin that was first reported to be present in increased levels in the blood of infected patients by Assicot et al.1 Since this sentinel report, numerous authors have investigated its role in differentiating and risk-stratifying infectious and noninfectious disease processes.2, 3 Despite extensive investigation, the procalcitonin test has not gained widespread use as a diagnostic tool in any patient population.4
The ability to accurately and rapidly identify patients with bacteremia is an important management issue for emergency physicians. One of the potential uses of the procalcitonin test in the emergency department (ED) is as a screening test for bacteremia. The availability of such a screening test would have utility in several clinical scenarios. A large area of potential utility is in the febrile pediatric population, particularly those at risk for occult bacteremia. Young children are often unable to localize their infection and the management, disposition, and prognosis all change according to the presence or absence of bacteremia.5, 6 In the adult population, approximately 50% of patients evaluated in the ED with undifferentiated hypotension or hypotension of uncertain cause are ultimately diagnosed with sepsis.7 Many of these patients will have normal body temperature and WBC counts, making the diagnosis even more nebulous.8 The importance of early detection in these cases is underscored by research documenting an unfavorable prognosis for adults with sepsis and bacteremia.9
At least 1 previous report asserted that a low serum procalcitonin level accurately rules out the diagnosis of bacteremia in adults.10 This meta-analysis evaluates the test characteristics of the procalcitonin test in the diagnosis of bacteremia in the ED setting.
Section snippets
Materials and Methods
The research question was, what is the diagnostic accuracy (eg, sensitivity and specificity) of the procalcitonin test in the diagnosis of bacteremia in the ambulatory population with suspected infection?
MEDLINE (January 1, 1970, through August 2005) was searched for English-language clinical studies assessing the diagnostic performance of procalcitonin test in the diagnosis of bacteremia. The search was updated in September 2006. The electronic search used the following terms or MeSH subject
Results
The comprehensive search yielded a total of 342 publications and 1 unpublished study. In the updated search (September 2006), 6 additional potentially relevant studies were identified, and after independent review they were all excluded (Figure 1 and Table 1).
After the relevance search (blinded interobserver agreement, κ=0.7), a complete article review was performed on the remaining 150 articles. Seventeen studies were included in the final analysis, providing a sample of 2,008 subjects (Han et
Limitations
Although our search was comprehensive, we did not search EMBASE or include foreign language studies.43, 44 Systematic reviews that include EMBASE and foreign language studies may yield slightly smaller estimates of effect for interventions; therefore, it is possible that our CIs are too small and our estimates of test performance are overly optimistic. Although we may have missed some articles, we used a comprehensive search using independent reviewers. Moreover, an updated search was completed
Discussion
This meta-analysis evaluates the test characteristics of the procalcitonin test in the diagnosis of bacteremia in ambulatory patients. Using pooled data from 17 studies comprising 2,008 subjects, we found the area under the summary receiver-operating characteristic to be 0.84, with the lower limit 95% CI of 0.75, indicating modest predictive ability of procalcitonin to diagnose bacteremia. Using the pooled sensitivity and specificity for the studies that used a test threshold of 0.5 or 0.4
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2019, Clinics in Laboratory MedicineCitation Excerpt :Furthermore, PCT has proved to be a useful and sensitive biomarker for the diagnosis of bacteremia/sepsis in children as well as elderly patients.60,61 Several meta-analyses have been performed on the diagnostic accuracy of PCT.62–66 Four of these meta-analyses identified PCT as a useful biomarker with at least good performance for the diagnosis of sepsis,63–66 whereas 1 meta-analysis identified only a moderate benefit in the detection of bacteremia/sepsis.62
Procalcitonin: Between evidence and critical issues
2019, Clinica Chimica Acta
Supervising editor: Brian H. Rowe, MD, MSc
Author contributions: AEJ and JAK conceived and designed the study. AEJ, JFF, JJB and JAK collected the data. AEJ and MDB analyzed the data. AEJ drafted the article, and all authors contributed to the final manuscript. AEJ takes responsibility for the paper as a whole.
Funding and support: The authors report this study did not receive any outside funding or support and there were no other conflicts of interest to declare. See the Manuscript Submission agreement form, published each month, for details of covered relationships.
Available online December 11, 2006.
Reprints not available from the authors.
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Dr. Fiechtl is currently affiliated with the Department of Emergency Medicine, Vanderbilt University, Nashville, TN.