Procalcitonin (PCT) measurement has been proposed to direct antibiotic use. We examined whether repeated PCT measurements (0, 6, and/or 12 hours) versus the initial measurement only (time 0) increased the sensitivity and specificity of PCT for diagnosing infection in intensive care unit patients. Infection was identified in 67/176 (38%) patients. The sensitivity of repeated versus the initial PCT measurement (with a cutoff value 0.5 ng/mL) was 52/67 (77%; 95% confidence interval [CI], 66%–87%) vs 46/67 (69%; 95% CI, 56%–79%; P = .04) and specificity 60/109 (55%; 95% CI, 45%–65%) vs 59/109 (54%; 95% CI, 44%–64%; P = 1.0). Repeat PCT evaluations over 12 hours did not provide a clinically significant improvement in diagnostic accuracy when compared to the initial single test.
From the *Department of Anesthesiology
†Department of Clinical Microbiology and Infectious Diseases
‡Hadassah-Hebrew University Medical Center, Jerusalem, Israel.
Published ahead of print 17 January 2018.
Accepted for publication January 17, 2018.
Funding: This study was supported by Brahms and Siemens, which provided the procalcitonin kits at no cost.
The authors declare no conflicts of interest.
P. D. Levin and M. J. Cohen contributed equally and share first authorship.
The information in this study was presented in part at the European Society of Intensive Care Medicine (ESICM) 27th Annual Congress, Barcelona, 2014.
Reprints will not be available from the authors.
Address correspondence to Shmuel Benenson, MD, MSc, Department of Clinical Microbiology and Infectious Diseases, Hadassah-Hebrew University Medical Center, PO Box 12000, Jerusalem 9112001, Israel. Address e-mail to Benenson@Hadassah.org.il.