Page 272 - The Vasculitides, Volume 1: General Considerations and Systemic Vasculitis

246 Christian Pagnoux and Gerard P. Cox

Table 1. (Continued)

Disease or disease group Comments

Hemostasis disorders Thrombotic thrombocytopenic Usually associated with an

purpura and idiopathic underlying lung condition to

thrombocytopenic purpura, when causing diffuse alveolar

anticoagulants, antiplatelet agents, hemorrhage

thrombolytics; disseminated

intravascular coagulation

Mitral stenosis and mitral

regurgitation

Pulmonary veno-

occlusive disease

Idiopathic pulmonary

hemosiderosis

Pulmonary embolism

Malignant conditions Lung cancer, pulmonary

angiosarcoma, Kaposi sarcoma,

multiple myeloma, acute

promyelocytic leukemia

Other conditions / High-altitude pulmonary edema,

miscellaneous barotrauma

Lymphangioleiomyomatosis

Pulmonary capillary

hemangiomatosis

Lymphangiography

Tuberous sclerosis

Abbreviations: ANCA: antineutrophil cytoplasm antibody; EGPA: eosinophilic granulomatosis with

polyangiitis; GBM: glomerular basement membrane; GPA: granulomatosis with polyangiitis;

MPA: microscopic polyangiitis.

Eosinophilic Lung Infiltrates

Lung infiltrates occur in up to three quarters of patients with EGPA corresponding to
eosinophilic pulmonary inflammation. On chest CT, they appear as patchy, multifocal, with
peripheral ground-glass attenuation; unilateral or bilateral, symmetrical or asymmetrical; and
sometimes labile, transient or migratory areas of consolidation (Figure 5). They may be
associated with pleural effusions mimicking chronic eosinophilic pneumonia, although the
latter presents most often with homogeneous and peripheral lung infiltrates. Bronchoalveolar
lavage or thoracentesis can demonstrate the predominant eosinophilic nature of the
abnormality, typical of EGPA, and exclude other diagnoses such as infection and alveolar
hemorrhage [23].

Fibrosis
Fibrosis is increasingly recognized as an infrequent complication of anti-MPO AAV,

most often with interstitial pneumonitis and fibrosis preferentially involving the lung bases
(Figure 6). Interstitial lung disease (ILD) usually occurs after onset of the vasculitis but can
precede extra-pulmonary manifestations by years [24]. The pathogenic mechanism of ILD is

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