Accurate diagnosis of different bronchopul-
monary diseases is important in clinical practice. This
study involved 20 healthy volunteers and 77 patients with
bronchopulmonary diseases, including chronic obstructive
pulmonary disease (COPD), bronchial asthma, pulmonary
tuberculosis, and community-acquired pneumonia. The
absorption spectrum of exhaled air samples was recorded
on an intra-cavity photo-acoustic gas analyzer (ILPA-1,
Special Technologies, Ltd., Russia) with photo-acoustic
detectors and CO 2 laser with a tuning range from 9.2 to
10.8 μm. In conclusion, analysis of the Mahalanobis
distance-based absorption spectral profiles of breath air
from bronchopulmonary patients and healthy volunteers
allows the formulation of a preliminary diagnosis.

• Diagnostics of bronchopulmonary diseases through Mahalanobis distance-based absorption spectral analysis of exhaled air