Systemic vasculitides (SVs) are characterized by inflammation of the blood vessels wall; the spectrum of their clinical manifestations depends on the type, extent, and location of affected vessels and the activity of systemic inflammation. The etiology of most primary SVs is unknown. Antineutrophil cytoplasmic antibodies (ANCAs) are implicated in its pathogenesis. The presence of ANCAa in patients' serum and the correlation of their level with the severity of clinical manifestations served as a basis for identifying a subgroup of systemic necrotizing vasculitides associated with ANCA synthesis: granulomatosis with polyangiitis (GPA), microscopic polyangiitis, and Churg – Strauss syndrome. GPA is characterized by systemic granulomatous necrotizing vasculitis involving the small vessels of the upper respiratory tract, lung, and kidney.

The paper describes a case of difficult diagnosis and successful rituximab (RTM) treatment of generalized GPA in a 45-year-old female patients. The disease occurred with local damage to the upper respiratory tract, granulomatous inflammation of the pulmonary vessels to form multiple infiltrates with lung tissue destruction elements and necrotizing glomerulonephritis. Despite intensive immunosuppressive treatment, there was a rapid GPA progression with the further development of respiratory failure, which had been induced by stenotic laryngitis subglottica leading to tracheostoma. Damage to the organ of vision could lead to severe complications, including amaurosis. RMT was shown to be effective in treating generalized GPA with a poor prognosis.