Patients with interstitial lung diseases (ILDs) come to medical attention mainly because of the onset of progressive exertional dyspnea or a persistent nonproductive cough. Hemoptysis, wheezing, and chest pain may be present. Often, the identification of interstitial opacities on chest x-ray focuses the diagnostic approach on one of the ILDs.
ILDs represent a large number of conditions that involve the parenchyma of the lung—the alveoli, the alveolar epithelium, the capillary endothelium, and the spaces between those structures—as well as the perivascular and lymphatic tissues. The disorders in this heterogeneous group are classified together because of similar clinical, roentgenographic, physiologic, or pathologic manifestations. These disorders often are associated with considerable rates of morbidity and mortality, and there is little consensus regarding the best management of most of them.
ILDs have been difficult to classify because >200 known individual diseases are characterized by diffuse parenchymal lung involvement, either as the primary condition or as a significant part of a multiorgan process, as may occur in the connective tissue diseases (CTDs). One useful approach to classification is to separate the ILDs into two groups based on the major underlying histopathology: (1) those associated with predominant inflammation and fibrosis and (2) those with a predominantly granulomatous reaction in interstitial or vascular areas (Table 261-1). Each of these groups can be subdivided further according to whether the cause is known or unknown. For each ILD there may be an acute phase, and there is usually a chronic one as well. Rarely, some are recurrent, with intervals of subclinical disease.
Table 261-1 Major Categories of Alveolar and Interstitial Inflammatory Lung Disease |Favorite Table|Download (.pdf)
Table 261-1 Major Categories of Alveolar and Interstitial Inflammatory Lung Disease
|Lung Response: Alveolitis, Interstitial Inflammation, and Fibrosis|
Drugs (antibiotics, amiodarone, gold) and chemotherapy drugs
Residual of acute respiratory distress syndrome
- Desquamative interstitial pneumonia
- Respiratory bronchiolitis–associated interstitial lung disease
- Langerhans cell granulomatosis (eosinophilic granuloma of the lung)
Idiopathic interstitial pneumonias
- Idiopathic pulmonary fibrosis (usual interstitial pneumonia)
- Acute interstitial pneumonia (diffuse alveolar damage)
- Cryptogenic organizing pneumonia (bronchiolitis obliterans with organizing pneumonia)
- Nonspecific interstitial pneumonia
Connective tissue diseases
- Systemic lupus erythematosus, rheumatoid arthritis, ankylosing spondylitis, systemic sclerosis, Sjögren's syndrome, polymyositis-dermatomyositis
Pulmonary hemorrhage syndromes
- Goodpasture's syndrome, idiopathic pulmonary hemosiderosis, isolated pulmonary capillaritis
Pulmonary alveolar proteinosis
Lymphocytic infiltrative disorders (lymphocytic interstitial pneumonitis associated with connective tissue disease)
- Tuberous sclerosis, neurofibromatosis, Niemann-Pick disease, Gaucher's disease, Hermansky-Pudlak syndrome
Gastrointestinal or liver diseases (Crohn's disease, primary biliary cirrhosis, chronic active hepatitis, ulcerative colitis)
Graft-versus-host disease (bone marrow transplantation; solid organ transplantation)
|Lung Response: Granulomatous|
|Hypersensitivity pneumonitis (organic dusts)||Inorganic dusts: beryllium, silica|
Granulomatosis with polyangiitis (Wegener's), allergic granulomatosis of Churg-Strauss
Sarcoidosis (Chap. 329), idiopathic pulmonary fibrosis (IPF), and pulmonary fibrosis associated with ...