Helpful Tips To Keep In Mind For Those Afflicted With Xeroderma Pigmentosum Xeroderma pigmentosum is a rare medical condition whereby individuals are unable to have direct contact with the sunlight and other sources of ultraviolet rays. Although it is classified as a rare disorder, it is one that is particularly burdensome and serious for those afflicted with xeroderma pigmentosum. The following paragraphs will provide some general tips for those afflicted with this condition to keep in mind.