[Bronchiolitis obliterans: technics of exploration and diagnosis]

Bronchiolitis obliterans is an anatomo-clinical entity which may, in young pediatric patients, follow severe viral infections, especially due to measles virus and adenoviruses. After a transient remission, the disease progresses to chronic respiratory failure with dyspneic paroxysms. Diagnosis is based on different investigations which confirm the absence of proximal bronchiolar obstruction and the presence of bronchiolar obliteration. Deficient pulmonary perfusion due to ventilatory defects are demonstrated by pulmonary scintigraphy and even better by digital subtraction pulmonary angiography. Obliteration of non-cartilaginous bronchioli by granulation tissue produces bronchiolar destruction and explains the permenence of alterations. Dissimilarity of the responses of children to acute respiratory viral infection remains unexplained. The degree of the viral load and of the initial immune deficiency as well as the persistence of the virus within the pulmonary tissue probably account for the chronic pulmonary damage.