806 Histopathology features of cutaneous acute graft-versus-host disease can be reliably detected by noninvasive reflectance confocal microscopy

BACKGROUND: The reliability to noninvasively identify features of inflammatory dermatoses by reflectance confocal microscopy (RCM) remains unknown. Specific consensus terminology with representative images is necessary ensure consistent feature-level interpretation among RCM readers. METHODS: Through an iterative process refinement and discussion five international experts, we developed a glossary aGVHD. In 17 lesions from 12 patients cutaneous aGVHD, four dermatopathologists readers independently evaluated the presence aGVHD in scanned histopathology slides 1.5x1.5 mm submosaics at 4 depths, respectively. Interobserver reproducibility was calculated mean pairwise difference U statistic. Concordance between modalities determined fraction agreement. RESULTS: We present 18 RCM. average interobserver (75%, confidence interval 71%−79%) did not differ significantly (80%, 76%−85%). concordance 59%. CONCLUSIONS: By using validated glossary, implementation can now be advanced variety conditions image set.