8-Isoprostane and leukotrienes in exhaled breath condensate in Czech subjects with silicosis

Abstract

Silicosis has progressive, but unpredictable development. There are no markers routinely available to measure the activity and prognosis of silicosis. 8-isoprostane, a marker of oxidative stress and leukotrienes B4, C4, D4, and E4 were measured in exhaled breath condensate in patients with silicosis. Sixty subjects were examined, with mean age 66.7 ± 2.0 yr and mean exposure to silica 23.6 ± 2.5 yr. The control group had 25 subjects, with mean age 64.7 ± 4.8 yr. Exhaled breath was collected using the EcoScreen (Jaeger, Germany); 8-isoprostane and leukotrienes were analyzed by high-performance liquid chromatography/mass spectrometry. Several lung functions parameters were impaired in silicotics in comparisons with the controls; ESR, α1-antitrypsin and proteinuria were higher in the silicotics. Antineutrophilic cytoplasmic antibodies were more frequent in the silicotics (39%) than in the controls (4%), (p=0.0017). The mean level of 8-isoprostane in the patients with silicosis was 73.6 ± 9.9 vs. 43 ± 10 pg/ml (p=0.0001) in the controls. Silica exposure category (high, medium, none) was positively associated with the level of 8-isoprostane. In the patients with complicated silicosis, a high level of 8-isoprostane was found more frequently (p=0.0194). Leukotriene D4 was also increased in the silicotics (21.1 ± 2.7 pg/ml) vs. the controls (14.7 ± 2.7 pg/ml), (p=0.001). No significant effect of smoking or alcohol consumption on the markers examined was seen. This is the first study using exhaled breath condensate analysis in patients with silicosis.