054 Combination of thymus and activation-regulated chemokine and soluble OX40 as a diagnostic biomarker for DIHS/DRESS

Abstract

Drug-induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms (DIHS/DRESS) is a severe drug-induced adverse reaction with fever, cutaneous eruptions, hematological abnormalities, organ dysfunction, and reactivation of human herpesvirus 6 (HHV-6). Although rapid diagnosis is necessary for the management of DIHS/DRESS, it is difficult to distinguish the early phase of DIHS/DRESS from other drug eruptions. We have previously reported that thymus and activation-regulated chemokine (TARC), which plays an important role in Th2-mediated immune-inflammatory processes such as atopic dermatitis, and serum soluble OX40 (CD134), which has an important role in allergic inflammation and functions as a cellular receptor for HHV-6 entry, can be a useful diagnostic marker for DIHS/DRESS. The sensitivity and specificity of sOX40 (cut-off value 213 pg/ml) for the diagnosis of DIHS/DRESS were 67% and 80%, respectively. Those of TARC (cut-off value 4000 pg/ml) were 72% and 77%, respectively. In this study, in order to reveal the relationship between serum soluble OX40 and TARC levels in the acute phase of DIHS/DRESS as well as the sensitivity and specificity of serological test using both soluble OX40 and TARC for diagnosis of DIHS/DRESS, we analyzed the sera of DIHS/DRESS patients presenting to our department. We found that the two markers were significantly correlated, and the combination of sOX40 and TARC significantly increased sensitivity to 85% but decreased specificity to 73%. The combined determination using sOX40 and TARC levels may be useful to increase the detection rate of DIHS/DRESS.