IL6 and infectious disease: After being referred to the infectious disease department, further laboratory tests were conducted, revealing elevated levels of IL-6 (263.00 pg/mL, normal < 7 pg/mL), IL-8 (68.88 pg/mL, normal < 20.60 pg/mL), PR3-ANCA (>400.00 RU/mL, normal < 20 RU/mL), and immunoglobulin G4 (IgG4) at 2.441 g/L.