Granulomatous Respiratory Disorders
Paul C. Stillwell, MD, FAAP, and Robin R. Deterding, MD
•Granulomatous lung disease is categorized on the basis of several features of the granulomas, such as caseating and noncaseating and infectious or noninfectious etiologic origin (Boxes 91-1 and 91-2).
•The common feature is the pathologic appearance of an aggregate of histiocytes that are elongated and have indistinct borders.
—Multinucleated giant cells, lymphocytes, and plasma cells may also be present.
—If central necrosis is present, the granuloma will appear to have caseation and is most commonly caused by an infection (Figure 91-1).
•Granulomatous lung diseases are often associated with granulomas in several other organ systems, including the skin, subcutaneous tissues, and lymph nodes.
•Notable causes of granulomatous lung disease include
▪A multisystem disease of unknown etiologic origins
▪Noncaseating granulomas are the hallmark pathologic finding.
Bird fancier disease
Hot tub lung
Granulomatosis with polyangiitis (formerly Wegener granulomatosis)
Eosinophilic granulomatosis with polyangiitis (formerly Churg-Strauss syndrome)
Chronic granulomatous disease
Common variable immunodeficiency (granulomatous lymphocytic interstitial lung disease)
Lymphoid interstitial pneumonitis
Bronchocentric granulomatosis (often associated with Aspergillus)
▪Pulmonary involvement occurs in approximately 85% of adult patients; it may be slightly less common in children, particularly those <5 years of age.
▪Other organ systems commonly affected include the eyes, reticuloendothelial system (liver, lymph nodes, and spleen), skin, heart, and central nervous system.
▪In the United States, sarcoidosis is more prevalent and more severe in the African American population.
—Granulomatous lymphocytic interstitial lung disease (GLILD) associated with common variable immunodeficiency has been recognized with increasing frequency and, in some areas, is more common than sarcoidosis.