Korean J Dermatol.  2022 Nov;60(9):549-558.

Correlation between the Peripheral Eosinophil Count and Disease Severity in Patients with Bullous Pemphigoid: A Retrospective 20-Year Single-Center Study

• Kwon HJ
• Yoon JH

Abstract

Background
Bullous pemphigoid (BP) is an autoimmune blistering disease. Studies have focused on eosinophils for their significant role in the pathogenesis of BP, as they not only secrete proteases and proinflammatory cytokines but also recruit other inflammatory cells.
Objective
To investigate the correlation among peripheral eosinophil count, clinical severity, and laboratory findings in patients with BP.
Methods
A total of 59 patients with BP were included in this study. Correlation analyses between peripheral eosinophil count and bullous pemphigoid disease activity index (BPDAI) score, duration of hospitalization, anti-bullous pemphigoid antigen 180 (anti-BP180) immunoglobulin G (IgG) antibody, anti-bullous pemphigoid antigen 230 (anti-BP230) IgG antibody, immunoglobulin E (IgE), C-reactive protein, and procalcitonin levels were performed. Simple and multiple linear regression analyses were conducted to evaluate whether peripheral eosinophil counts could independently affect the BPDAI score and hospitalization duration.
Results
The peripheral eosinophil count was positively correlated with the initial skin, mucosa, total BPDAI score (p＜0.001, p=0.027, and p＜0.001, respectively), hospitalization days (p=0.032), anti-BP180 IgG antibody (p ＜0.001), anti-BP230 IgG antibody (p＜0.001), and IgE (p＜0.001). Furthermore, not only peripheral eosinophil count but also anti-BP180 IgG antibody, anti-BP230 IgG antibody, and IgE levels independently affected both the initial total BPDAI score (p＜0.05) and hospitalization duration (p＜0.05).
Conclusion
Based on our results, the peripheral eosinophil count can influence both clinical severity and laboratory findings. Additionally, it can indicate the clinical severity and prognosis of BP. Therefore, we suggest that the peripheral eosinophil count could be a useful marker for predicting clinical outcomes in patients with BP.

Keyword

Autoantibody; Bullous pemphigoid; Cytokines; Eosinophils; Immunoglobulins