Pulmonary Manifestation of Granulomatosis With Polyangiitis: A Challenging Case Presentation

Abstract

Granulomatosis with polyangiitis (GPA), formerly known as Wegener's granulomatosis, is a rare and potentially life-threatening autoimmune disease characterized by antineutrophil cytoplasmic antibody (ANCA)-associated vasculature inflammation. It presents as a systemic autoimmune disease with necrotizing granulomatous inflammation and pauci-immune small vessel vasculitis. This case initially posed a diagnostic challenge due to its atypical presentation and was misdiagnosed as hypersensitivity pneumonitis. The avian precipitin screening assay was positive in our patient, which may be consistent with bird breeder's lung disease or a non-specific reactivity of the chicken antigen test. However, the presence of positive c-ANCA was pivotal for the GPA diagnosis. Here, we describe in detail the clinical manifestations, diagnostic approach, and treatment of GPA in a 54-year-old female who presented with alveolar hemorrhage, but no renal involvement. Treatment involved the use of high-dose corticosteroids to suppress the autoimmune response. Finally, we discuss the striking response of this unique form of granulomatosis with polyangiitis to corticosteroid treatment and emphasize the importance of early initiation of treatment.

Keywords: corticosteroides; diffuse alveolar hemorrhage; diffuse interstitial lung disease; ground-glass opacity; thoracic radiology.

Figure 1. Posteroanterior chest radiograph demonstrating bilateral interstitial syndrome

The image shows diffuse bilateral infiltrative opacities predominantly in the middle and lower regions.

Figure 2. Chest computed tomography scan in the parenchymal window showing alveolar hemorrhage

Chest computed tomography scan showing bilateral diffuse ground glass associated with septal and non-septal thickening, giving a crazy paving appearance, more marked in the upper lobes with sparing of the subpleural region, suggesting alveolar hemorrhage.

Figure 3. Bronchoalveolar lavage showing hemosiderosis

Bronchoalveolar lavage showing predominantly macrophagic histiocytic alveolitis, with hemosiderosis. Perls' staining revealed intense hemosiderin pigmentation, leaving the histiocyte nuclei visible. This pigmentation is rated mostly at 3, according to the Golde score, and was assessed on 100 histiocytic cells.