Evaluation of procalcitonin as a diagnostic and prognostic marker in patients with sepsis, severe sepsis and septic shock associated with ventilator-associated pneumonia

Objectives

Although the significance of procalcitonin (PCT) has been evaluated for general populations of patients with sepsis attributed to various infections, application as a marker of severity with both diagnostic and prognostic implications in patients with ventilator-associated pneumonia (VAP) has not been specifically studied.

Methods

Serum samples were collected on the first, third, fifth and seventh days of symptoms from 68 patients with sepsis, severe sepsis/shock (ASCP/SCCM 1992) and VAP. APACHE II and SOFA scores were measured on the first day of the symptoms. Patients were followed-up for 28 days for overall survival. PCT was estimated in sera of patients by immunochemiluminometric assay.

Results

Among 68 patients, 34 presented with sepsis, five with severe sepsis and 29 with septic shock. Mean age (years, ± standard deviation) was 57.86 ± 18.85; 48 patients were male and 20 female. APACHE II and SOFA (mean ± standard deviation) were 18.28 ± 6.11 and 7.64 ± 3.24, respectively. After 28 days of follow-up, 38 patients were alive and 21 have died. Mean PCT concentrations (ng/ml) on days 1, 3, 5 and 7 in patients with sepsis, severe sepsis and septic shock are presented in Table 1.

Table 1 Mean procalcitonin concentrations (ng/ml)

The mean ± standard error serum concentrations of PCT of survivors at days 1, 3, 5 and 7 were 0.71 ± 0.19, 0.45 ± 0.09, 0.35 ± 0.05 and 1.42 ± 1.04, respectively. Respective values in non-survivors were 1.83 ± 0.86 (P = not significant compared with survivors), 2.63 ± 1.08 (P = 0.05), 3.61 ± 1.33 (P = not significant) and 2.89 ± 0.99 (P = 0.02).

Conclusions

PCT is a crucial marker of overall survival in patients with septic syndrome and VAP. This suggestion is further supported by the fact that PCT correlates to the severity of disease constituting an objective marker of sepsis.