Thelansis

  Xeroderma pigmentosum (XP) constitutes a rare hereditary skin disorder characterized by an exceptional vulnerability to ultraviolet (UV) triggered alterations in both skin and ocular tissues, alongside the development of numerous skin malignancies. The condition is categorized into eight distinct complementation groups based on the affected gene: classical XP (XPA to XPG) and XP variant (XPV). The gravity of clinical manifestations and the age of onset exhibit substantial variation, contingent upon sunlight exposure and the specific complementation group. Approximately 50% of afflicted individuals display acute sensitivity to sunlight during the initial months of life, characterized by severe sunburn or persistent erythema that takes weeks to ameliorate. Conversely, some individuals do not manifest any sunburn reaction but gradually manifest pronounced freckling in sun-exposed regions. Patients typically exhibit xerotic skin and hypo- or hyperpigmented lesions. Notably, a profo...