ABSTRACT
DAVID A. ZISMAN, JOHN A. BELPERIO, RAJAN SAGGAR, RAJEEV SAGGAR, MICHAEL C. FISHBEIN, and JOSEPH P. LYNCH III David Geffen School of Medicine at UCLA, Los Angeles, California, U.S.A.
I. Introduction
The interstitial lung diseases (ILDs) are a varied group of conditions characterized by inflammation and fibrosis of the lung parenchyma. Pulmonary hypertension (PH) has been described in most of these conditions. In ILD, the term PH is preferred over pulmonary arterial hypertension (PAH) as PAH refers to World Health Organization (WHO) group 1, that is, idiopathic pulmonary arterial hypertension (IPAH) and connective tissue disease (CTD)-associated pulmonary hypertension. PH complicating ILD is included under WHO class 3 (hypoxia-associated PH) (1). PH has been described in nearly all patients with advanced pulmonary Langerhans cell histiocytosis (PLCH) (2-4), in advanced cases of lymphangioleiomyomatosis (LAM), hypersensitivity pneumonitis (HP), amyloidosis, drugs, asbestosis, pneumoconioses, bronchoalveolar carcinoma, lymphangitic carcinomatosis, and radiation (5-12). This chapter will focus on PH complicating idiopathic pulmonary fibrosis (IPF) and sarcoidosis since most of the investigations have focused on these two conditions. Given that CTD-associated PH patients commonly have a primary vasculopathic component, this group will be the topic of a separate discussion.
