Update on cryptogenic organising pneumonia (idiopathic bronchiolitis obliterans organising pneumonia).

Organising pneumonia, defined by intraalveolar buds of connective tissue, may be a disorder secondary to a determined cause (infectious agents, drugs) or occurring in a specific context (as the connective tissue disorders). It may also be a cryptogenic interstitial pneumonia with characteristic clinical and imaging features and especially an excellent response to corticosteroids.