A significant difference was observed in the expression of IL-1β within the epithelium across pooled samples from the SJS/TEN patients (average immunofluorescence [IF] intensity: 1348 a.u.), lichen planus (LP) patients (average IF intensity: 1279 a.u.), and normal controls (average IF intensity: 1168 a.u.)(p < 0.0001). The gene discussed is IL1B; the disease is toxic epidermal necrolysis.