In Critically Ill Patients, Serum Procalcitonin Is More Useful in Differentiating between Sepsis and SIRS than CRP, Il-6, or LBP

Table 4

Sensitivity, specificity, predictive values, and diagnostic odds ratios using the highest values of all biomarkers within the first 24 hrs of ICU admission.

	Sensitivity	Specificity	PPV	NPV	DOR (95% CI)
CRP cut-off value 50 μg/mL	88%	23%	45%	71%	2.1 (0.6–7.3)
PCT cut-off value 2 ng/mL	97%	80%	78%	97%	120.6 (14.4–1006)
PCT cut-off value 10 ng/mL	66%	93%	88%	79%	26.1 (6.6–103.8)
IL-6 cut-off value 50 pg/mL	91%	41%	53%	86%	6.7 (1.8–25.4)
LBP cut-off value 30 μg/mL	53%	91%	81%	73%	11.3 (3.3–39.3)

Sensitivity: percentage of septic patients with positive test.
Specificity: percentage of nonseptic patients with negative test.
PPV (positive predictive value): percentage of test-positive patients with sepsis.
NPV (negative predictive value): percentage of test-negative patients without sepsis.
DOR (diagnostic odds ratio): [sensitivity/(1 − sensitivity)]/[(1 − specificity)/specificity]: the ratio of the odds of disease with a positive test relative to the odds of disease with a negative test.