Granulomatosis With Polyangiitis Misdiagnosed as Tuberculosis: A Case Report.

Granulomatosis with polyangiitis (GPA), formerly known as Wegener's granulomatosis, is a rare autoimmune disorder characterized by necrotizing vasculitis affecting small to medium-sized vessels. This condition most commonly affects the lungs, kidneys, and upper respiratory tract. Early recognition and treatment are critical to prevent severe complications and improve prognosis. This report presents the case of a 48-year-old male with GPA, with primary pulmonary and articular involvement, who presented with respiratory symptoms and was initially misdiagnosed as having pulmonary tuberculosis due to cavitary lesions on imaging.