Circulating eosinophil and neutrophil counts correlate with disease severity in bullous pemphigoid

Background: Bullous pemphigoid (BP) is an autoimmune subepidermal blistering disease characterized by tissue-bound and circulating autoantibodies directed against BP180 and/or BP230 antigens. Various inflammatory cells are involved in the development of blister in BP. Objective: The aim of this study was to evaluate the correlation between peripheral leukocyte counts and BP severity. Methods: We retrospectively included 60 patients with BP, who had not been treated with systemic steroid at the time of blood sampling. The patients were classified into two groups, those with admission history (admission group) and those without admission history (non-Admission group). Disease severity was evaluated using three parameters: Admission history, initial steroid dosage, and modified version of a pemphigus scoring system. We evaluated the correlation between peripheral leukocyte counts and disease severity measured by the three parameters. Results: The admission group showed a significant increase in disease severity measured by initial steroid dosage and severity score compared with the non-Admission group. Additionally, the admission group had increased total leukocyte, eosinophil, and neutrophil counts. In the correlation study, the peripheral eosinophil and neutrophil counts showed positive correlation with BP severity evaluated by both initial steroid dosage and the pemphigus scoring system. Conclusion: Peripheral eosinophil and neutrophil counts can be used as a marker in predicting disease severity in patients with BP.