Risk and Impact of Cytomegalovirus Infection in Bullous Pemphigoid Patients Treated With Immunosuppressive Agents

Severe infection is associated with increased mortality in patients receiving systemic corticosteroid therapy, including those with bullous pemphigoid (BP). Cytomegalovirus (CMV) reactivation represents a highly probable and underrecognized cause of death in immunosuppressive individuals. The aim of this study was to evaluate the association between CMV reactivation and disease course in patients with BP, and to develop a clinical scoring system for the prediction and early detection of CMV reactivation. A retrospective analysis of 41 patients with BP who received systemic corticosteroid therapy in our institution was conducted. Clinical and laboratory data were evaluated to identify factors associated with CMV reactivation, and a scoring system was developed to support both prediction and detection. Compared with CMV-negative BP patients, CMV-positive patients exhibited a more severe and protracted course, characterized by a higher incidence of complications. In addition, CMV-positive patients had more extensive areas of blistering and erosion than CMV-negative patients. Neutrophil-lymphocyte ratio, platelet count, eosinophil count, serum sodium concentration level, and systemic corticosteroid dose were identified as key indicators for predicting and early detection of CMV reactivation. The proposed scoring system demonstrated high sensitivity (95.5%) and specificity (89.5%) for detecting CMV reactivation. Timely initiation of anti-CMV therapy following the detection of CMV reactivation was crucial for preventing fatal complications. A newly-invented scoring system may serve as a useful tool for predicting and detecting CMV reactivation in BP. Early identification of high-risk cases may enable timely anti-CMV therapy to prevent CMV disease leading to better outcomes.