Arterial Carboxyhemoglobin Measurement Is Useful for Evaluating Pulmonary Inflammation in Subjects with Interstitial Lung Disease.
Objective The arterial concentration of carboxyhemoglobin (CO-Hb) in subjects with inflammatory pulmonary disease is higher than that in healthy individuals. We retrospectively analyzed the relationship between the CO-Hb concentration and established markers of disease severity in subjects with interstitial lung disease (ILD). Methods The CO-Hb concentration was measured in subjects with newly diagnosed or untreated ILD and the relationships between the CO-Hb concentration and the serum biomarker levels, lung function, high-resolution CT (HRCT) findings, and the uptake in gallium-67 (67Ga) scintigraphy were evaluated. Results Eighty-one non-smoking subjects were studied (mean age, 67 years). Among these subjects, (A) 17 had stable idiopathic pulmonary fibrosis (IPF), (B) 9 had an acute exacerbation of IPF, (C) 44 had stable non-IPF, and (D) 11 had an exacerbation of non-IPF. The CO-Hb concentrations of these subjects were (A) 1.5±0.5%, (B) 2.1±0.5%, (C) 1.2±0.4%, and (D) 1.7±0.5%. The CO-Hb concentration was positively correlated with the serum levels of surfactant protein (SP)-A (r=0.38), SP-D (r=0.39), and the inflammation index (calculated from HRCT; r=0.57) and was negatively correlated with the partial pressure of oxygen in the arterial blood (r=-0.56) and the predicted diffusion capacity of carbon monoxide (r=-0.61). The CO-Hb concentrations in subjects with a negative heart sign on67Ga scintigraphy were higher than those in subjects without a negative heart sign (1.4±0.5% vs. 1.1±0.3%, p=0.018). Conclusion The CO-Hb levels of subjects with ILD were increased, particularly during an exacerbation, and were correlated with the parameters that reflect pulmonary inflammation.
Division of Infectious Diseases and Pulmonary Medicine, Department of Internal Medicine, National Defense Medical College, Japan.
Yu
Y
Hara
Masaharu
M
Shinkai
Soichiro
S
Kanoh
Yuji
Y
Fujikura
Bruce
B
K Rubin
Akihiko
A
Kawana
Takeshi
T
Kaneko
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers; D002263:Carboxyhemoglobin / Q000032:analysis*; D005260:Female; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000097:blood; D017563:Lung Diseases, Interstitial / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000097:blood; D011014:Pneumonia / Q000097:blood*; D037662:Pulmonary Surfactant-Associated Protein A / Q000032:analysis; D012189:Retrospective Studies
D015415:Biomarkers; D037662:Pulmonary Surfactant-Associated Protein A; D002263:Carboxyhemoglobin; D010100:Oxygen