[Update on non-specific interstitial pneumonia: a pattern, a clinical entity or different phenotypes? Surgical or bronchoscopic diagnosis?].

Nonspecific interstitial pneumonia (NSIP) was initially defined in 1994 as a histopathologic pattern, characterized by the presence of varying proportions of lung interstitial inflammation and fibrosis, with a temporally uniform lung involvement, that can be found in the presence of a wide variety of clinical and radiologic contexts. Idiopathic NSIP, considered as a "provisional clinical diagnosis" until recently, has now been recognized as a distinct clinical entity, interestingly occurring mostly in middle-aged and never-smoker women, with dyspnoea, cough, ground glass at high resolution CT scan of the chest, and with a very good prognosis. Though this recent evidence, the diagnosis of idiopathic NSIP is still based on histology obtained from surgical lung biopsy, as recommended by the American Thoracic Society/European Respiratory Society statement: are less invasive procedures, such as transbronchial lung biopsies and bronchoalveolar lavage, useful tools in the initial approach of this clinical entity?