Mortality risk prognosis

Procalcitonin (PCT) is a biomarker associated with the inflammatory response to bacterial infection that aids in the risk assessment of critically ill patients. The percent change in PCT result over time aids in the prediction of cumulative 28-day mortality in patients with severe sepsis and septic shock.

This calculator has been validated only for changes in PCT from the day severe sepsis or septic shock was diagnosed (Day 0) or the day thereafter (Day 1) to the fourth day (Day 4) after diagnosis.

PCT Calculator
Day 0 (if none Day 1)
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  • The PCT results must be entered with only two decimal points of precision
  • If no Day 0 result is available, Day 1 result must be entered in its place
  • If more than one PCT result is available on Day 0 (or Day 1), the highest result must be entered
  • The two results have to be obtained on the same instrument
ng/mL or µg/L
Day 4
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  • The PCT results must be entered with only two decimal points of precision
  • If more than one PCT result is available on Day 4, the most recent result must be entered
  • The two results have to be obtained on the same instrument
ng/mL or µg/L
* Mandatory fields
Error icon Missing required fields
Error icon PCT results must be between 0.05 and 1000 ng/mL with only two decimals
Error icon Invalid date range
Results
Information icon The ΔPCT is calculated with entire precision but only two decimals are displayed.
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Formula

ΔPCT = PCTDay 0 - PCTDay 4 X 100
PCTDay 0
ΔPCT = PCTDay 1 - PCTDay 4 X 100
PCTDay 1
ΔPCT = PCTDay 0 - PCTDay 4 X 100
PCTDay 0
 
ΔPCT = - X 100
ΔPCT = PCTDay 1 - PCTDay 4 X 100
PCTDay 1
 
ΔPCT = - X 100

Mortality risk

The table below shows the 28-day cumulative mortality risk by binary group (ΔPCT ), by patient location at Day 4 (), by instrument () and by initial PCT result.

ΔPCT
Day 0 - Day 4		 Initial PCT result 28 day mortality
≤ 80% decline
(95% CI)		 All PCT results 31.3%
(24.5-38.1%)
≤ 2.0 ng/mL

26.4%
(15.8-37.1%)
> 2.0 ng/mL

34.1%
(25.3-42.9%)
> 80% decline
(95% CI)		 All PCT results 18.4%
(10.0-26.8%)
≤ 2.0 ng/mL

2.2%
(0.0-15.1%)
> 2.0 ng/mL

20.3%
(11.1-29.5%)
ΔPCT
Day 0 - Day 4		 Initial PCT result 28 day mortality
≤ 80% decline
(95% CI)		 All PCT results 11.4%
(6.8-16.1%)
≤ 2.0 ng/mL

9.5%
(3.9-15.1%)
> 2.0 ng/mL

14.1%
(6.1-22.1%)
> 80% decline
(95% CI)		 All PCT results 5.4%
(1.8-9.1%)
≤ 2.0 ng/mL

3.7%
(0.0-11.0%)
> 2.0 ng/mL

5.8%
(1.6-10.0%)
ΔPCT
Day 1 - Day 4		 Initial PCT result 28 day mortality
≤ 80% decline
(95% CI)		 All PCT results 31.6%
(24.7-38.5%)
≤ 2.0 ng/mL

22.2%
(11.6-32.7%)
> 2.0 ng/mL

36.8%
(27.8-45.7%)
> 80% decline
(95% CI)		 All PCT results 18.4%
(10.1-26.7%)
≤ 2.0 ng/mL

12.6%
(0.0-34.0%)
> 2.0 ng/mL

19.2%
(10.3-28.1%)
ΔPCT
Day 1 - Day 4		 Initial PCT result 28 day mortality
≤ 80% decline
(95% CI)		 All PCT results 10.1%
(5.7-14.5%)
≤ 2.0 ng/mL

8.1%
(2.9-13.3%)
> 2.0 ng/mL

13.0%
(5.2-20.9%)
> 80% decline
(95% CI)		 All PCT results 7.0%
(2.8-11.2%)
≤ 2.0 ng/mL

0.0%
(0.0-13.2%)
> 2.0 ng/mL

8.5%
(3.5-13.5%)
ΔPCT
Day 0 - Day 4		 Initial PCT result 28 day mortality
≤ 80% decline
(95% CI)		 All PCT results 31.0%
(24.2-37.8%)
≤ 2.0 ng/mL

27.0%
(16.3-37.8%)
> 2.0 ng/mL

33.5%
(24.6-42.3%)
> 80% decline
(95% CI)		 All PCT results 19.2%
(10.7-27.6%)
≤ 2.0 ng/mL

1.8%
(0.0-12.8%)
> 2.0 ng/mL

21.4%
(12.1-30.7%)
ΔPCT
Day 0 - Day 4		 Initial PCT result 28 day mortality
≤ 80% decline
(95% CI)		 All PCT results 10.9%
(6.3-15.4%)
≤ 2.0 ng/mL

9.2%
(3.8-14.7%)
> 2.0 ng/mL

13.4%
(5.3-21.5%)
> 80% decline
(95% CI)		 All PCT results 6.1%
(2.2-10.0%)
≤ 2.0 ng/mL

4.2%
(0.0-12.2%)
> 2.0 ng/mL

6.5%
(2.1-10.8%)
ΔPCT
Day 1 - Day 4		 Initial PCT result 28 day mortality
≤ 80% decline
(95% CI)		 All PCT results 30.8%
(23.9-37.7%)
≤ 2.0 ng/mL

22.2%
(11.8-32.7%)
> 2.0 ng/mL

35.6%
(26.6-44.5%)
> 80% decline
(95% CI)		 All PCT results 20.2%
(11.7-28.6%)
≤ 2.0 ng/mL

2.2%
(0.0-14.2%)
> 2.0 ng/mL

22.5%
(13.3-31.8%)
ΔPCT
Day 1 - Day 4		 Initial PCT result 28 day mortality
≤ 80% decline
(95% CI)		 All PCT results 9.8%
(5.5-14.2%)
≤ 2.0 ng/mL

6.9%
(2.1-11.8%)
> 2.0 ng/mL

13.9%
(6.0-21.8%)
> 80% decline
(95% CI)		 All PCT results 7.3%
(2.9-11.6%)
≤ 2.0 ng/mL

0.2%
(0.0-14.2%)
> 2.0 ng/mL

8.7%
(3.5-13.8%)

Warnings and precautions

  • These results were obtained in a multicenter study on a population of adult patients recruited across 13 investigational sites in the US. The tested population was comprised of 598 patients with severe sepsis or septic shock admitted for ICU care in which PCT values were measured on Days 0, 1, and 4
  • Predictive values may differ significantly at other institutions and PCT assay results should not be the sole basis for assessing mortality risk
  • Changes in PCT should always be interpreted in the context of the clinical status of the patient and other laboratory results