Intensive Care Med (2005) 31:1495–1500 DOI 10.1007/s00134-005-2818-7 ORIGINAL Rogier M. Determann Julian L. Millo SØbastien Gibot Johanna C. Korevaar Margreeth B. Vroom Tom van der Poll Christopher S. Garrard Marcus J. Schultz Serial changes in soluble triggering receptor expressed on myeloid cells in the lung during development of ventilator-associated pneumonia Received: 13 April 2005 Accepted: 7 September 2005 Published online: 30 September 2005  Springer-Verlag 2005 R. M. Determann ( ) ) · M. B. Vroom · M. J. Schultz Department of Intensive Care Medicine, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands e-mail: r.m.determann@amc.uva.nl Tel.: +31-20-5666345 Fax: +31-20-5669568 J. L. Millo · C. S. Garrard Intensive Care Unit, John Radcliff Hospital, Oxford, UK S. Gibot RØanimaton Medicale, Hôpital Central, Nancy, France J. C. Korevaar Department of Epidemiology and Biostatistics, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands T. van der Poll Department of Internal Medicine, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands Abstract Objective: To determine the diagnostic role of soluble trig- gering receptor expressed on myeloid cells (sTREM)-1 in non-directed bronchial lavage fluid in ventilator- associated pneumonia (VAP). Design: Non-directed bronchial la- vage fluid and plasma were collected on alternate days in critically ill me- chanically ventilated patients from the start of ventilatory support until complete weaning from the ventila- tor. Soluble TREM-1 levels were measured by an enzyme-linked im- munosorbent assay. Setting: A gen- eral adult medical and surgical uni- versity hospital intensive care unit. Patients: Nine patients who devel- oped VAP and 19 patients who did not develop VAP (controls). Results: Plasma levels of sTREM-1 did not change significantly in either patient group. While in controls concentra- tions of sTREM-1 in non-directed bronchial lavage fluid did not change significantly over time, in patients who developed VAP levels of sTREM-1 in non-directed bronchial lavage fluid increased towards the diagnosis of VAP. A cut-off value for non-directed bronchial lavage fluid sTREM-1 levels of 200 pg/ml on the day of VAP had a diagnostic sensi- tivity of 75% and a specificity of 84%. Sensitivity increased when taking into account all sTREM-1 levels higher than 200 pg/ml from the 6-day period before the day of diag- nosis that were preceded by an in- crease of at least 100 pg/ml (sensi- tivity 88%, specificity 84%). Conclusions: Soluble TREM-1 is a potential biomarker of VAP. Keywords Biological marker · Diagnosis · Mechanically ventilated · Non-directed bronchial lavage fluid · Soluble triggering receptor expressed on myeloid cells · Ventilator- associated pneumonia Introduction The diagnosis of ventilator-associated pneumonia (VAP) remains a major challenge for intensive care unit (ICU) physicians [1, 2]. Although a presumptive clinical diag- nosis of VAP is often made on the basis of presence of a combination of new radiographic infiltrates on chest ra- diography, fever, leukocytosis, hypoxemia and/or puru- lent tracheal secretions, such an approach inevitably leads to overestimation of the incidence of VAP and subsequent unwanted excessive antibiotic use [3]. Invasive or non- invasive microbiological diagnostic procedures require