Increased soluble CD14 levels in BAL fluid in pulmonary tuberculosis.

INTRODUCTION CD14 is a cell surface glycoprotein expressed mainly on mature monocytes and macrophages. Soluble CD14 (sCD14) is present in normal plasma and is found increased in serum of patients with septicemia, polytrauma, and sarcoidosis. In active sarcoidosis, increased levels of sCD14 in BAL supernatant have been demonstrated. STUDY OBJECTIVE To investigate sCD14 levels in BAL of pulmonary tuberculosis (PTB), another inflammatory disease characterized by granuloma formation. METHODS BAL was performed in 12 patients with active but untreated PTB and 12 healthy persons. Cytologic and immunocytologic characteristics were determined. sCD14 was measured by a sandwich enzyme-linked immunosorbent assay. RESULTS The level of sCD14 in patients with PTB was increased compared with controls (mean +/- SEM: 34.4 +/- 9.6 ng/mL vs 11.5 +/- 2.2 ng/mL; p = 0.02). No correlation was found between sCD14 levels and BAL cell differentials or lymphocyte surface markers. CONCLUSION Similar to sarcoidosis, increased levels of sCD14 are found in BAL supernatant of PTB patients.