Soluble Triggering Receptor Expressed on Myeloid Cell-1 Is Increased in Patients With Ventilator-Associated Pneumonia: A Preliminary Report

Abstract

The diagnosis of ventilator-associated pneumonia (VAP) can be difficult. Soluble triggering receptor expressed on myeloid cell-1 (sTREM-1) has been reported to be elevated in BAL fluid from patients with VAP.To evaluate the utility of sTREM-1 in the diagnosis of VAP in BAL fluid and the fluid collected in the expiratory trap from the ventilator, the exhaled ventilator condensate (EVC).We prospectively collected BAL fluid and EVC from 23 patients clinically suspected of having VAP. A sensitive enzyme-linked immunosorbent assay was developed to measure sTREM-1. The results derived from this assay were confirmed using an immunoblot technique. The presence of VAP was clinically determined using a modified clinical pulmonary infection score of > 6.VAP was diagnosed in 14 of 23 patients. sTREM-1 was detected in the EVC from 11 of 14 subjects with VAP, but from only 1 of 9 subjects without VAP, and was significantly higher in the pneumonia patients and when expressed as picograms per milliliter or picograms per microgram protein (p = 0.005, both comparisons). In contrast, sTREM-1 was detected in the BAL fluid of all 14 VAP subjects but also in 8 of 9 subjects with no pneumonia, and did not differ in the VAP subjects compared to the nonpneumonia subjects when expressed as picrograms per milliliter or picograms per microgram protein (p > 0.05 both comparisons).sTREM-1 is detectable in EVC and may be useful in establishing or excluding the diagnosis of VAP.