PROGNOSTIC VALUE OF EOSINOPHIL CATIONIC P ROTEIN AND MYELOPEROXIDASE ASSESSMENT IN BRONCHOALVEOLAR LAVAGE IN PATIENTS WITH IDIOPATHIC PULMONARY FIBROSIS

Idiopathic pulmonary fibrosis (IPF) is characterized by a chronic infl ammatory process in the lower respiratory tract of unknown etiology an d poor prognosis. There is evidence that cytotoxic mediators released by neutrophils and eosinophils, such as myeloperoxidase (MPO) and eosi nophil cationic protein (ECP) play a central role in the pathogenesis of this disease. The aim of this study was to assess disease activity in patients with IPF by measuring MPO and ECP concentrations in bronch oalveolar lavage (BAL). 14 patients with IPF had significantly higher concentrations of BAL-MPO and ECP (median = 117.2 mug/l, range: 4-217 mug/l and median = 16 mug/l, range: 4-34 mug/l, respectively) than pat ients with sarcoidosis (n = 9) (median = 6.5 mug/l, range: 4-12 mug/l and median = 7.1 mug/l, range: 2-13 mug/l, respectively) or pneumonia (n = 13) (median = 10.8 mug/l, range: 5-14 mug/l and median = 7.6 mug/ l, range: 3-10 mug/l, respectively) (p < 0.01). Follow-up of MPO and E CP concentrations in BAL was performed in 8 patients with IPF before a nd after 4 weeks high-dose and 12 months low-dose corticosteroid thera py. Changes in MPO and ECP levels paralleled the clinical course and s uccessful treatment resulted in a significant decrease of both MPO and ECP concentrations (p < 0.05), while clinical deterioration or treatm ent failure was associated with an increase of BAL-MPO and ECP levels. Increased MPO and ECP concentrations in BAL seem to reflect ongoing d isease activity and may, be useful prognostic markers in the managemen t of patients with IPF.