Bronchoalveolar lavage chitotriosidase activity as a biomarker of sarcoidosis.

BACKGROUND Chitotriosidase (CTO) was shown to be a good biomarker of sarcoidosis. Increased levels in bronchoalveolar lavage fluid (BALF) were reported and associated with more severe forms of the disease. OBJECTIVES The aim of the study was to evaluate the value of CTO in BALF as a routine biomarker of sarcoidosis. METHODS The study included 85 patients in 9 control subjects in whom serum and BALF CTO were measured. RESULTS Significantly higher CTO levels were detected in BALF of sarcoidosis patients than in control subjects (p < 0.001). There was good correlation between serum and BALF CTO levels in sarcoidosis patients (Spearman's Rho 0.481, p < 0.001). Serum but not BALF CTO had good correlation with clinical parameters. Only in a group of patients with BALF CTO above upper normal range there was association of BALF CTO with impaired FVC (p = 0.020) and chest radiograph score (0-2 vs. 3-4, p = 0.016). CONCLUSIONS In comparison to serum CTO no additional benefit of determining CTO in BAL for routine sarcoidosis workup was shown.