Prognostic value of raised procalcitonin when combined with routine biomarkers of sepsis among critically ill patients

Introduction

In sepsis the timing of treatment is vital in survival of the patients. Procalcitonin (PCT) by itself cannot reliably differentiate sepsis from other noninfective causes [1]. PCT, however, may help to identify the critically ill patients with poor prognosis when used in combination with other markers, such as C-reactive protein (CRP) and white cell count (WCC). The aim of this retrospective study was to look at prognosis of patients admitted to the ICU with a raised PCT >10 ng/ml. A novel approach for prediction of prognosis and severity may be to combine the biomarkers with PCT.

Methods

We looked at all the patients with a raised PCT (PCT > 10 ng/ml), admitted to a general ICU in a district general hospital over a period of 17 months. The total number of patients admitted over this time was 976 (surgical patients 67% and medical patients 33%) with a corresponding unit mortality of 16% and a hospital mortality of 21%. The corresponding WCC and CRP were noted. Our patients had similar SOFA and IPS scores so they were comparable with each other.

Results

The overall mortality of patients with a PCT > 10 ng/ml was 28%, compared with our ICU mortality of 16%. When the biomarkers are combined, the mortality of patients with all biomarkers raised (> 3 markers – abnormal WCC, increased CRP, increased PCT) was 30%. The mean length of stay in patients with all biomarkers raised was 10.5 days, compared with the length of stay in patients with an isolated marker of 6.5 days (isolated raise of WCC or CRP).

Conclusion

These results support the use of PCT as prognostic marker in the critically ill, but also emphasize the role of CRP for added accuracy in predicting mortality. The WCC seems to have less significance as a predictive indicator. This may even be important in an inpatient setting to identify the high-risk patients for early intervention.