Serum CC-chemokine ligand 18 concentration predicts outcome in idiopathic pulmonary fibrosis.
BACKGROUND
Idiopathic pulmonary fibrosis (IPF) is a devastating lung disease with a poor prognosis. There is great effort to find predictors of outcome. Conclusive data for any serum biomarker are lacking. We have recently documented that serum CCL18 concentrations correlate with the course of pulmonary function data in patients with pulmonary fibrosis of various causes.


OBJECTIVE
To test the value of serum CCL18 concentrations in IPF, we included 72 patients in a prospective study.


METHODS
IPF was defined according to the ATS/ERS criteria. Serum CCL18 concentrations were measured by a commercially available ELISA. Patients were followed for 24 months. Pulmonary function tests were performed at least every 6 months.


RESULTS
Baseline serum CCL18 concentrations predicted the change in TLC and FVC at the 6-month follow-up. Receiver operating characteristics (ROC) revealed a significant relation between survival and baseline CCL18 concentrations. By ROC analysis, the cutoff value with the highest diagnostic accuracy was defined as 150 ng/ml (sensitivity, 0.83; specificity, 0.77). There was a significantly higher mortality in patients with serum CCL18 concentrations above 150 ng/ml (P < 0.0001). The hazard proportional ratio adjusted for age, sex, and baseline pulmonary function data was 8.0. There was a higher incidence of disease progression in the group with high serum CCL18 concentrations.


CONCLUSIONS
Our data demonstrate that serum CCL18 concentrations have a predictive value in IPF and may be a useful tool in the clinical management of patients with IPF and in clinical trials.
Prasse
Antje
A
Department of Pneumology, University Freiburg, Germany. antje.prasse@uniklinik-freiburg.de
Probst
Corinna
C
Bargagli
Elena
E
Zissel
Gernot
G
Toews
Galen B
GB
Flaherty
Kevin R
KR
Olschewski
Manfred
M
Rottoli
Paola
P
Müller-Quernheim
Joachim
J
D000368:Aged; D015415:Biomarkers / Q000097:blood; D019742:Chemokines, CC / Q000097:blood*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000097:blood* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D012129:Respiratory Function Tests; D016019:Survival Analysis
D015415:Biomarkers; C111792:CCL18 protein, human; D019742:Chemokines, CC