Exhaled nitric oxide is increased in active fibrosing alveolitis

Study objectives: Interstitial inflammation is a major aggravating factor i n fibrosing lung disease associated with scleroderma (FASSc) and cryptogeni c fibrosing alveolitis (CFA), Exhaled nitric oxide (NO) production is incre ased in asthma and bronchiectasis and reflects the degree of inflammation. me investigated whether measuring levels of exhaled NO is valuable in asses sing disease activity in patients with CFA and patients with FASSc, Measurements and results: NO levels were measured in 11 patients with CFA ( mean age +/- SEM, 58 +/- 12 years old; 5 were male) and 17 patients with FA SSc (mean age, 48 +/- 9 years old; 5 were male), and they were compared to BAL cell counts and lung function. Patients with CFA and FASSc had elevated NO levels (11.2 +/- 1.0 parts per billion [ppb] and 9.8 +/- 1.0 ppb, respe ctively p > 0.05), whereas in a group of 13 nonsmoking normal subjects, the NO levels were not elevated (6.9 +/- 0.5 ppb; p < 0.05). Patients with FAS Sc (n = 8),who had active BAL (defined as either lymphocytes > 14%, neutrop hils > 4%, or eosinophils > 3%) had significantly higher NO levels (13.2 +/ - 1.8 ppb), and neutrophil (16.5 +/- 4.0%) and lymphocyte (26.8 +/- 3.4%) B AL cell counts than did patients with FASSc who had inactive BAL (6.7 +/- 1 .2 ppb; 1.3 +/- 1.0% and 7.5 +/- 1.3%, respectively; p < 0.05), There was a significant correlation between exhaled NO and lymphocyte cell count in pa tients with FASSc (r = 0.58; p < 0.05), All patients with CFA had active BA L;however, those treated with corticosteroids (12.9 +/- 1.0% ppb, p < 0.05) had lower NO levels (9.0 +/- 1 ppb) and higher BAL lymphocyte cell counts (16.6 +/- 2.0%) than did those not treated with corticosteroids (7.2 +/- 1. 7%; p < 0.05), Conclusions: We conclude that exhaled NO may be a useful addition to BAL ce ll counts in disease monitoring.