Procalcitonin in early onset ventilator-associated pneumonia

Ventilator-associated pneumonia (VAP) is a significant problem in intensive care and there exists great demand for a suitable biomarker. Procalcitonin (PCT) has been proposed as a candidate marker.

To assess the clinical usefulness of monitoring PCT concentrations in non-surgical patients with early onset VAP.

Thirty-four patients were enrolled with early onset VAP defined as VAP diagnosed between 48 h and 6 days of the onset of mechanical ventilation. Serum PCT was measured on days 1, 2, 3, 5, 6 and 7.

The mortality rate was 21%. Non-survivors had significantly elevated PCT levels on days 3 and 7. For non-survival, the areas under the receiver operator curve (AUC) for PCT were 0.762 [95% confidence interval (CI): 0.6-0.923] on day 3 and 0.754 (95% CI: 0.586-0.922) on day 7. Among septic patients, PCT was significantly higher on days 1, 2, 3, 5, and 7, with the highest AUC on day 1 (0.783; 95% CI: 0.626-0.94): a cut-off of 1 ng/mL on day 1 had a positive predictive value of 0.813 for the development of septic shock.

No association was found between PCT concentration and the adequacy of antibiotic therapy or the aetiology of VAP. In logistic regression analysis, PCT was not significantly correlated with poor outcome. Although PCT levels were higher in non-survivors and those who developed septic shock, PCT is not a strong predictor of these outcomes.