Idiopathic pulmonary fibrosis (IPF), synonymous with
cryptogenic fibrosing alveolitis (CFA), is a progressive and
usually fatal disease of unknown cause characterized by
sequential acute lung injury with subsequent scarring and
end-stage lung disease. Historically, IPF/CFA encompassed a
heterogeneous group of different histological and clinical
entities arising in an idiopathic setting. Recently, the
American Thoracic Society (ATS) and European Respiratory Society
(ERS) core committee has redefined diagnostic criteria for both
IPF/CFAand idiopathic interstitial pneumonias confining the term
IPF/CFA to patients with a histological pattern of usual
interstitial pneumonia on lung biopsy. This review attempts to
refine the clinico-radiological-pathological features that
together define IPF/CFA as it is understood today, and to
summarize the rationale of new therapeutic approaches based on
the current understanding of the pathogenetic mechanisms.