New Biomarkers to Diagnose Ventilator Associated Pneumonia: Pentraxin 3 and Surfactant Protein D
To detect the most effective biomarker to confirm ventilator associated pneumonia (VAP).
Fifty patients with VAP suspicious diagnosis and 30 healthy patients were recruited. Suspicion of VAP was established if patients met the modified CPIS score ≥ 6 points. The confirmation of VAP was defined by the quantitative culture of nonbronchoscopic bronchoalveolar lavage (BAL) >105 CFU/ml of pathogenic microorganism. Serum samples for determination of C-reactive protein (CRP), procalcitonin (PCT), pentraxin 3 (PTX3), surfactant protein D (SPD) were collected on suspected VAP.
Twenty seven of 50 patients were accepted as confirmed VAP group whose nonbronchoscopic BAL cultures were positive and rest of them were accepted as unconfirmed VAP group. PTX3, PCT and SPD levels were significantly higher in confirmed VAP group, (P = 0.021, P = 0.007, P < 0.001 respectively). There were no significant differences in CRP levels between the two groups (P = 0.062). The most sensitive marker for diagnosing VAP was SPD (P < 0.001). Receiver operating characteristic (ROC) curve for modified clinical pulmonary infection score (CPIS) to confirm VAP was evaluated (AUC 0.741 ± 0.07, P < 0.001) and the optimal cutoff value was >7 with a sensitivity of 51.85% and a specificity of 91.3%. SPD levels were significantly higher in Acinetobacter baumannii and Pseudomonas aeruginosa infected patients than culture negative patients (P < 0.001).
The index findings suggest that serum SPD is the most sensitive biomarker in diagnosis of VAP and it can be used as an early and organism specific marker for Acinetobacter baumannii and Pseudomonas aeruginosa.
KeywordsSurfactant protein D Pentraxin 3 Ventilator associated pneumonia
Area under ROC curve
Colony forming units
Clinical pulmonary infection score
Enzyme-linked immunosorbent assay
Pediatric logistic organ dysfunction
Pediatric intensive care unit
Pediatric risk of mortality
Receiver operating characteristic
Surfactant protein D
Ventilator associated pneumonia
NUT and BNA conceptualized the study and its design. NUT and BNA participated in data collection and diagnostic work-up of study participants. BDE and SM analyzed and interpreted the data. NUT drafted the manuscript, which was revised after critical inputs from BNA, SM, BDE. All authors approved the final version of the manuscript, as submitted. BNA is consultant of incharge and will act as guarantor for this paper.
Compliance with Ethical Standards
Conflict of Interest