Abnormal exhaled ethane concentrations in scleroderma.
Scleroderma (systemic sclerosis) is a chronic multisystem autoimmune disease in which oxidative stress is suspected to play a role in the pathophysiology. Therefore, it was postulated that patients with scleroderma would have abnormally high breath ethane concentrations, which is a volatile product of free-radical-mediated lipid peroxidation, compared with a group of controls. There was a significant difference (p<0.05) between the mean exhaled ethane concentration of 5.27 pmol ml(-1) CO(2) (SEM=0.76) in the scleroderma patients (n=36) versus the mean exhaled concentration of 2.72 pmol ml(-1) CO(2) (SEM=0.71) in a group of healthy controls (n=21). Within the scleroderma group, those subjects taking a calcium channel blocker had lower ethane concentrations compared with patients who were not taking these drugs (p=0.05). There was a significant inverse association between lung diffusion capacity for carbon monoxide (per cent of predicted) and ethane concentration (b=-2.8, p=0.026, CI=-5.2 to -0.35). These data support the presence of increased oxidative stress among patients with scleroderma that is detected by measuring breath ethane concentrations.
Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 20705, USA. kcope@jhsph.edu
K A
KA
Cope
S F
SF
Solga
L K
LK
Hummers
F M
FM
Wigley
A M
AM
Diehl
T H
TH
Risby
D001944:Breath Tests; D004980:Ethane / Q000032:analysis*; D000431:Ethanol / Q000032:analysis; D006801:Humans; D015227:Lipid Peroxidation; D008176:Lung Volume Measurements; D008875:Middle Aged; D012595:Scleroderma, Systemic / Q000503:physiopathology*
D000431:Ethanol; D004980:Ethane