ABSTRACT
Idiopathic pulmonary fibrosis (IPF) is a distinct clinical syndrome of unknown
cause characterized by progressive dyspnea, dry cough, basilar crackles, a
restrictive ventilatory defect on pulmonary function tests (PFTs), and the his-
tological pattern usual interstitial pneumonitis (UIP) on surgical lung biopsy
(1,2). Cryptogenic fibrosing alveolitis (CFA) and IPF are synonymous terms (2).
The histological pattern UIP is found in IPF (1,2), but may be observed in other
etiologies as well [e.g., collagen vascular disease (CVD), asbestosis, and diverse
occupational, environmental, or drug exposures] (2-4). In 2002, the American
Thoracic Society (ATS) and European Respiratory Society (ERS) published a
classification schema recognizing seven idiopathic interstitial pneumonias (IIPs)
(Table 1) (5). IPF/UIP is the most common of the IIPs, comprising 47% to 71%
cases; nonspecific interstitial pneumonia (NSIP) accounts for 13 to 48% (6-12).
In this chapter, we focus on IPF. The remaining IIPs are discussed elsewhere in
this book.
