A possible alteration of surfactant in broncho-alveolar lavage fluid from healthy smokers compared to non-smokers and patients with sarcoidosis.

In disorders affecting the alveoli and lung interstitium and altered composition of the epithelial lining fluid, i.e. the surfactant, may affect the outcome of the disease. The phospholipid composition in bronchoalveolar lavage (BAL) fluid was determined in healthy non-smoking (n = 8) and smoking (n = 12) volunteers, and in non-smoking patients with clinically active sarcoidosis (n = 7). The total amount of phosphatidylcholines (median +/- SD) were in the non-smoking control group (21.8 +/- 5.7 mumol/L) and in the non-smoking sarcoidosis group (26.1 +/- 9.1 mumol/L), while healthy smokers had significantly (p < 0.05 for both) lower amounts (14.6 +/- 5.6 mumol/L). The composition of phosphatidylcholines was similar in all three groups with one exception. Palmitoylmyristoyl-phosphatidylcholine constituted a significantly higher fraction among the smokers (12.7 +/- 2.1 mol%) compared to the non-smoking control group (10.6 +/- 1.4 mol%; p < 0.05) and the sarcoidosis group (10.6 +/- 0.6 mol%; p < 0.01). In conclusion, no quantitative or qualitative differences in phosphatidylcholines were observed between non-smoking healthy volunteers and non-smoking patients with clinically active sarcoidosis. However, in smoking healthy volunteers the total amount of phosphatidylcholines was reduced and their composition altered. Earlier reported conflicting results may be due to the fact that the smoking habits have not been considered.