Exhaled Breath Condensate Revealed as a Promising Tool for Diagnosis of CF, Other Lung Diseases

Researchers at the Hellenic Cancer Society and the Biomedical Research Foundation, Academy of Athens in Greece conducted a review on exhaled breath condensate analysis as a tool to assess lung function in patients with respiratory disorders. The study was recently published in The Scientific World Journal and is entitled “Exhaled Breath Condensate: Technical and Diagnostic Aspects.”

Exhaled breath condensate (EBC) analysis is a new non-invasive method for biomarker detection in the respiratory tract, especially the lower track. EBC is the product of cooling and condensation of the individual’s exhaled aerosol; it is an easy, user-friendly procedure with EBC being collected during quiet breathing.

EBC is a promising lung function test that can be easily applied to assess airway function in patients with several lung diseases, including cystic fibrosis (CF). CF is a rare, life-threatening genetic disease in which a defective gene (CFTR) induces a salt imbalance, causing the body to form unusually thick, sticky mucus that can obstruct the airways and promote dangerous lung infections resulting in serious respiratory and also gastrointestinal manifestations. The majority of CF patients die due to respiratory failure. It is estimated that almost 75,000 individuals worldwide suffer from CF, including 30,000 individuals in the United States.

In this study, researchers conducted a systematic review of the literature to assess the 30-year advance of EBC research. The team gathered articles published on EBC’s diagnostic, methodological and technical aspects from 1980 to October 2014. In the end, 228 research and review articles were selected.

The team found that the number of articles covering EBC topics has been increasing in the last years, reflecting an increasing interest in this technique. They reported that EBC is an innovative, advantageous, non-invasive, effortless and painless technique. It is a manageable tool for application of technologically advanced methods of biomedical research, having the potential to provide information regarding metabolic, proteomic and genomic biomarkers.

In terms of limitations, the team emphasizes that most of the studies available were conducted on a small-scale, and that the lack of studies with large cohorts of patients impairs the determination and establishment of reference values for EBC biomarkers. Another limitation is the poor reproducibility of these biomarkers, making it difficult to define accurate diagnostic markers. This limitation is also linked to the fact that despite the extensive research on lung diseases like CF, cancer, asthma and chronic obstructive pulmonary disease (COPD), there is still no specific biomarker that allows for an accurate diagnosis and disease monitoring.

The research team concluded that EBC analysis is a promising technique in the diagnosis of respiratory conditions but that it requires further studies before it can be successfully applied in clinical practice.