CXCL8 and chronic obstructive pulmonary disease: For longitudinal monitoring and prognostication in non-neutropenic patients (including COPD) with IPA, consider GMI (peak value in the first ICU week > 0.483; 51.5%, 81.9%) and PTX3 (plasma > 7.11 ng/mL; 82.8%, 73.4%; BALF > 4.29 ng/mL; 81.4%, 67.1%), alongside CRP and selected airway cytokines (such as IL-8: serum 93.46 pg/mL; 83.78%, 81.25%; BALF 325.4 pg/mL; 85.14%, 75.00%).