Bronchiolitis obliterans organizing pneumonia.

ABSTRACT Bronchiolitis obliterans with organizing pneumonia (BOOP) is now established as a distinct clinicopathologic entity, yet it may be overlooked by clinicians due to unfamiliarity and its non-specific presentation. It can be either idiopathic or associated with a variety of causes, such as infections, drugs, radiation or connective tissue diseases. A lung biopsy is needed to provide histopathologic confirmation. Usually prognosis is good, and the response to steroids may be dramatic, but occasionally BOOP may be fatal or runs a chronic relapsing course. This article is an updated review on current knowledge regarding BOOP.