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The idiopathic interstitial pneumonias (IIPs) encompass a subcategory of interstitial lung diseases (ILDs) that pose significant diagnostic and management challenges. The general diagnostic approach to these disorders is discussed elsewhere in this textbook (Chapter 54), as is the diagnosis and management of idiopathic pulmonary fibrosis (IPF), (Chapter 56). This chapter details the classification, diagnosis, and management of non-IPF forms of IIPs including nonspecific interstitial pneumonia (NSIP), organizing pneumonia (OP), desquamative interstitial pneumonia (DIP), and respiratory bronchiolitis-associated interstitial lung disease (RB-ILD), acute interstitial pneumonia (AIP), and lymphocytic interstitial pneumonia (LIP). Historical perspectives, current definitions, and epidemiologic information will be provided along with clinical aspects, imaging, and pathologic findings. Each section ends with a discussion of current therapeutic options. This information is summarized in Table 57-1.

Table 57-1Key Features of Idiopathic Interstitial Pneumonias

Nonspecific Interstitial Pneumonia

The important entity of nonspecific interstitial pneumonia is discussed below.

Definition and historical perspectives

In 1994, the term ...

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