[2000 classification of idiopathic interstitial lung diseases]

Diagnosis of interstitial lung diseases was recently improved by the use of diagnostic tools, such as high-resolution Computed Tomography, and by new insights in their pathogenesis and histology. This led the American Thoracic Society and the European Respiratory Society to propose a new classification of these diseases, in the aim to facilitate early diagnosis and specific care.

Standard radiography gives the first suspicion of chronic diffuse infiltrative lung disease, and anamnesis and physical examination are essential steps of etiological diagnosis. High-Resolution computed tomography confirms the diagnosis of diffuse infiltrative lung disease. Longitudinal lung function tests are essential to assess the consequences of the lung disease. Lung biopsies are often, but not systematically, a useful tool. The 2000 classification consists of seven entities of idiopathic interstitial diseases which are defined on clinical, radiological and pathological criteria: idiopathic pulmonary fibrosis, non-specific interstitial pneumonia, cryptogenic organizing pneumonia, acute interstitial pneumonia, respiratory bronchiolitis associated interstitial lung disease, desquamative interstitial pneumonia and lymphoid interstitial pneumonia. The most frequent is Idiopathic Pulmonary Fibrosis, which has a poor prognosis.

This new classification results from a multidisciplinary confrontation with chest physicians, radiologists and pathologists. A better characterization of anatomoclinical entities should lead to a better pronostic evaluation, more informative comparisons of published studies, and therefore to rational therapeutic approach.