ABSTRACT
Biological markers in various compartments of the human body have demonstrated potential value in diagnosis, prediction, guidance of therapy as well as in monitoring the clinical course of diseases of the airways and the lung. But only certain surrogate parameters are from clinical value, such as procalcitonin in pneumonia and sepsis, alpha-1-antitrypsin to diagnose alpha-1-antitrypsin deficiency, D-Dimers to detect emboli, nitric oxide in exhaled air in asthma, or isolation of germs from sputum to guide antibiotic treatment. Quantification of numerous markers in exhaled breath condensate or the detection of compounds in exhaled air are more recent attempts to further elucidate those biomarkers for clinical use. In general, biomarkers have an important supportive value in addition to routine diagnostic methods. The article reviews recent data regarding the usefulness of markers in non-malignant pulmonary diseases.
