**11. Special situations**

Parentage of a patient with obstruction initially suffered from asthma and who subsequently becomes a smoker can be a clinical problem almost insoluble.

The combination of smoking and disease interstitial chronic or pulmonary fibrosis has been highlighted in several recent publications. A recent epidemiological study in area cardiology, MESA study, performing CT lung, indicates that this match will be anecdotal in the future.

Respiratory bronchiolitis with interstitial respiratory disease (RB / ILD) is another example of interstitial and bronchial disease secondary to smoking. Some patients who do not meet the criteria for COPD are patients with severe by accelerating their natural evolution. (Figure 3)
