Granulomatosis with polyangiitis in gingiva: A rare case of isolated presentation.

Granulomatosis with polyangiitis (GPA) is a rare autoimmune disease characterized by necrotising granulomatous inflammation of upper and lower respiratory tract, vasculitis and glomerulonephritis. This ailment may present with cough, haemoptysis, sinusitis, nasal deformity, skin lesions, malaise, fever, anorexia, and weight loss. Oral manifestation includes strawberry gingivitis, which is a pathognomonic clinical presentation. Here, we present a case of GPA in gingiva as the first manifestation. Clinical examination of the oral cavity revealed granular, erythematous gingival enlargement in the lower anterior teeth region involving papilla, marginal and attached gingiva with shiny and pebbled surface. Histopathological examination showed pseudoepitheliomatous hyperplasia with vasculitis and inflammation in the connective tissue, neutrophilic infiltration and abscess formation with haemorrhage were noted. Laboratory investigations revealed Proteinase 3 (PR3) antigen and Glomerular basement membrane (GBM) antigen were positive. Clinical, histopathological and laboratory investigations enabled the diagnosis of Granulomatosis with Polyangiitis. We present this rare case report of GPA with primary manifestation in gingiva.