Goodpasture's Syndrome and p-ANCA Associated Vasculitis in a Patient of Silicosiderosis: An Unusual Association

Abstract

Introduction. Goodpasture's syndrome is a rare clinical entity and is characterized by circulating autoantibodies which are principally directed against the glomerular/alveolar basement membrane. The etiology of Goodpasture's syndrome is still unknown. Lung involvement occurs as a result of lung injury and the exposure of new epitopes to the immune system. Recently, several studies have suggested the role of silica as one of etiological factors in ANCA associated vasculitis and glomerulonephritis. Materials and Methods. We present a case of a 40-year-old welder with silicosiderosis, who developed anti-GBM disease with p-ANCA positivity. Case Report. Patient presented to an emergency with gradually increasing breathlessness along with renal failure and died after short hospital stay. Autopsy pathology findings revealed crescentic glomerulonephritis with linear glomerular basement membrane antibody deposition, splenic vasculitis, pulmonary haemorrhage, and pulmonary silicosiderosis. Conclusion. This case reinforces the role of environmental triggers like exposure to silica, metal dust, and tobacco in pathogenesis of Goodpasture's syndrome and p-ANCA associated vasculitis.

Figure 1

Photomicrograph showing (a) swollen and flea bitten appearance of kidney, (b) glomeruli showing crescent formation (H&E, ×400), (c) linear staining of glomerular basement membrane for IgG on immunofluorescence, and (d) no electron dense deposits seen on ultrastructural examination.

Figure 2

Photomicrograph showing (a) voluminous, heavy, and subcrepitant lungs which on cut surface showed haemorrhagic consolidation, (b) dominantly fresh alveolar hemorrhages (H&E, ×200), (c) linear IgG deposits on alveolar lining and capillary basement membrane by immunofluorescence, (d) pleura with numerous 0.2-0.3 cm white nodules scattered throughout the surface, (e) interstitial nodules well demarcated from adjacent lung parenchyma characterized by concentrically arranged fibroblasts and hyalinized lamellated arrangement of the collagen bundles (inset showing small polarizable refractile oval to needle shaped particles within the nodules) (H&E, ×100), (f) Perl's stain highlighting the iron content in dust macules in peribronchiolar and perivascular location composed of macrophages containing brown black particles (Perl's stain, ×200).

Figure 3

Photomicrograph showing fibrinoid necrosis of the wall of trabecular vessels of the spleen along with occasional giant cells indicative of vasculitis (H&E, ×200, ×400).