The diagnosis is based on the following criteria coded by the American College of Rheumatology (a score ≥ 6 is required): obstructive airway disease (+3), nasal polyps (+3), mononeuritis multiplex (+1), blood eosinophil count ≥ 1 × 109/L (+5), extravascular eosinophilic-predominant inflammation on biopsy (+2), positive test for cytoplasmic antineutrophil cytoplasmic antibodies (cANCA) or antiproteinase 3 (anti-PR3) antibodies (−3), and hematuria (−1) [27]. Here, PRTN3 is linked to nasal cavity polyp.