We report the case of a 13-year-old young lady with a one year reccuring bullous dermatitis history for which the diagnostic hypothesis of dermatitis arterfacta was made. This hypothesis was made by the pathologist, without it being suggested by the dermatologist, after observing singular histological lesions coresponding to a cutaneous blister associated with epidermic necrosis with multinucleated keratinocytes. When dermatitis artefacta is suspected, a biopsy is usually conducted to rule out differential diagnosis such as auto-immmune dermatitis when there is a blister. Confession from patients is rarely obtained. Therefore, having positive histogical clues for dermatitis artefacta would be of a great use to help making the diagnosis in difficult cases.