Researching the Changes of Serum Procalcitonin Levels in Ventilator-Associated Pneumonia Patients

Background: Ventilator-Associated Pneumonia (VAP) is the most common hospital acquired infection in the intensive care unit with high mortality rate. The role of the clinical symptoms for the VAP diagnosis is limited. Procalcitonin (PCT), currently interested biomarkers, plays an important role in the diagnosis and the outcome of the ventilator-associated pneumonia patients. Objective: To evaluate the changes of serum procalcitonin level for the diagnosis and the prognosis of the ventilator-associated pneumonia patients. Materials and Methods: One hundred twenty two mechanical ventilated cases at Intensive Care Unit were divided into the VAP group (n=63) and the non-VAP group (n=59) depending on whether the patients developed VAP after 48 hour of endotracheal intubations and mechanical ventilation or not. The serum procalcitonin level, Clinical Pulmonary Infection Score (CPIS) described by Pugin et al. or Schurink et al. were determined at the following times: The starting of mechanical ventilation, the VAP onset, at days 3, 5, 7 after VAP. Results: Serum procalcitonin level >0.5 ng/ml had a role at quite good VAP diagnosis with the Sensitivity (Se) 68.25% and the Specificity (Sp) 89.83%. When both Pugin’s CPIS and procalcitonin were positive, the diagnostic efficiency were Se 59.58% and Sp 97.06%. When both Schurink’s CPIS and procalcitonin were positive, the diagnostic efficiency were Se 51.99% and Sp 92.07%. Mortality rate was 5% at serum procalcitonin level <0.5 ng/ml but it was 75% at serum procalcitonin level ≥10 ng/ml. Conclusions: Procalcitonin has both the diagnosis value in the ventilatorassociated pneumonia patients and the prognostic value in their treatment outcome and the mortality rate. Serum procalcitonin concentration >0.5 ng/ml had a role at quite good VAP diagnosis with the sensitivity 68.25% and the specificity 89.83%. The higher serum procalcitonin level was associated with the higher mortality rate and the mortality rate was 75% at serum procalcitonin level ≥10 ng/ml in ventilator-associated pneumonia.