Granulomatosis with Polyangiitis (GPA) is a rare autoimmune disease that causes inflammation of blood vessels, leading to damage in various organs, particularly the lungs, kidneys, and sinuses. It is characterized by the formation of granulomas, which are clusters of immune cells that form in response to inflammation. The exact cause of GPA is unknown, but it is believed to involve a combination of genetic and environmental factors. Symptoms may include persistent sinusitis, coughing, shortness of breath, and kidney problems. Early diagnosis and treatment are crucial to manage the condition and prevent serious complications.