Neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio are positively correlated with disease activity of bullous pemphigoid

Bullous pemphigoid (BP) is a complex inflammatory process with elevated levels of autoantibodies, eosinophils, neutrophils, and various cytokines. Hematological inflammatory biomarkers can reflect inflammatory state in various diseases. Up to now, the correlations of hematological inflammatory biomarkers and disease activity of BP remain unknown. The purpose of this study was to clarify the associations between hematological inflammatory biomarkers and disease activity of BP. The levels of neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), platelet-to-neutrophil ratio (PNR) and mean platelet volume (MPV) of 36 untreated BP patients and 45 age and gender matched healthy controls were detected by routine blood tests. The correlations between hematological inflammatory markers and clinical characteristics of BP were statistically analyzed. The Bullous Pemphigoid Disease Area Index (BPDAI) was used to measure disease activity of BP. The mean levels of NLR, PLR, PNR and MPV in 36 untreated BP patients were 3.9, 157.9, 45.7 and 9.4 fl, respectively. Increased NLR (p < 0.001), PLR (p < 0.01), and MPV (p < 0.001) but decreased PNR (p < 0.001) were observed in BP patients when compared with healthy controls. In BP patients, the levels of NLR were positively correlated to BPDAI Erosion/Blister Scores (p < 0.01); and the levels of NLR and PLR were both positively correlated to BPDAI without Damage Score (both p < 0.05) and BPDAI Total Score (both p < 0.05). No correlation was found in other statistical analyses between hematological inflammatory markers and clinical characteristics in BP patients involved in the present study. Therefore, NLR and PLR are positively correlated with disease activity of BP.