Use of the routine complete blood count to predict steroid resistance in patients with chronic obstructive pulmonary disease

The aim of the present study was to investigate the significance of complete blood count, lymphocyte subpopulations, and cytokines in the peripheral blood in order to evaluate steroid resistance in patients with chronic obstructive pulmonary disease (COPD). Methods. Forty five patients with acute exacerbation of COPD (AECOPD) who underwent bronchoscopy the next day after hospital admission were included in the study. The patients were considered as steroid-sensitive or steroid-resistant according to the ability of dexamethasone to inhibit 50% of interleukin-8 production by alveolar macrophages. Complete blood count, lymphocyte subpopulations, cytokines, immunoglobulin E, and hormone level were measured in the peripheral blood of all patients with COPD. Results. Macrophage migration inhibitory factor (MIF) level, neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) were higher, and absolute and relative eosinophil numbers were lower in steroid-resistant patients with COPD compared to steroid-sensitive COPD patients. Absolute eosinophil number below the cut-off value of 0.126 × 109/L was predictive for steroid resistance with the sensitivity of 83.3%, the specificity of 55.6% and the area under ROC curve (AUC) of 0.677. Relative eosinophil number below 1.2% predicted steroid resistance with sensitivity, specificity and AUC of 83.3%, 63.0%, and 0.751, respectively. NLR, PLR, and MIF higher than 2.75, 116, and 2.24 ng/mL, respectively, predicted steroid resistance with the sensitivities of 66.7%, 61.1%, and 72.2%, respectively; the specificities of 74.1%, 77.8%, and 70.4%, respectively; and the AUCs of 0.731, 0.678, and 0.740, respectively. The combination of relative eosinophil number, NLR and PLR increased the sensitivity to 83.3%, specificity to 77.8%, and AUC to 0.805. The combination of relative eosinophil number, PLR and MIF increased the sensitivity to 83.3%, specificity to 88.9%, and AUC to 0.889. Conclusion. Steroid-resistant and steroid-sensitive COPD patients differ in absolute and relative eosinophil numbers, LNR, PLR, and MIF level. These parameters could be used to predict steroid resistance in COPD.