According to the data, EGPA patients with PN were more prone to weight loss, arthritis or joint pain, faster ESR, and higher CRP and RF, but they did not show a significant difference about the involvement of vital organs, including the lung, kidney, CNS, heart, or digestive system, which also suggested a reason why PN did not cause poor prognosis. The gene discussed is CRP; the disease is arthritic joint disease.