BACKGROUND: Actinic Prurigo (AP) is a chronic pruritic dermatosis of unknown cause affecting sun exposed skin in defined ethnic groups with characteristic MHC alleles. However, the cutaneous dendritic cells have not been assessed. OBJECTIVE: To assess in situ the epidermal Langerhans Cell (LC) status in Actinic Prurigo. STUDY DESIGN: Fresh skin samples from three AP patients were used to evaluate in situ the epidermal LC, comparing lesional and non-lesional sites in each subject. SETTING: AP patients attending the Dermatology Department at the Hospital M. Gea-Gonzalez in Mexico city. METHODS: Lesional and non-lesional skin samples were taken from each subject to prepare both epidermal sheets and conventional tissue sections. Three markers restricted to LC in epidermis (CD1a, ATPase, MHC-II) were used to quantify the LC per area in epidermal sheets. RESULTS: Compared to non-lesional skin from the same subject, a significant reduction in the number of LC per area of epidermis was found in lesional skin; with any of the three markers evaluated. CONCLUSION: The frequency of epidermal LC decreases importantly in lesional skin from AP patients.