Table 1.

Histological and clinical classification of idiopathic interstitial pneumonias^*[9,10]

Histological patterns	Clinical, radiological, and pathological diagnoses
Usual interstitial pneumonia	Idiopathic pulmonary fibrosis/ cryptogenic fibrosing alveolitis
Nonspecific interstitial pneumonia	Nonspecific interstitial pneumonia (provisional)**
Organizing pneumonia	Cryptogenic organizing pneumonia***
Diffuse alveolar damage	Acute interstitial pneumonia
Respiratory bronchiolitis	Respiratory bronchiolitis interstitial lung disease
Desquamative interstitial pneumonia	Desquamative interstitial pneumonia
Lymphocytic interstitial pneumonia	Lymphocytic interstitial pneumonia

^*Unclassifiable interstitial pneumonia: some cases are unclassifiable for a variety of reasons

^**This group represents a heterogeneous group with poorly characterized clinical and radiological features that need further study

^***COP is the preferred term, but is synonymous with idiopathic bronchiolitis obliterans organizing pneumonia