Hereditäre Photodermatosen

Abstract

Hereditary photodermatoses are characterized by an increased photosensitivity caused by an inherited single gene defect. With few exceptions, they manifest in early childhood, reveal heterogeneous clinical symptoms, and are difficult to treat. Although these diseases are rare, it is very important to make an accurate diagnosis on the basis of clinical symptoms, specific diagnostic tests, and direct DNA analysis. We review the spectrum of inherited photodermatoses, including porphyria cutanea tarda, erythropoietic protoporphyria, actinic prurigo, Kindler syndrome, and disorders associated with a defect in DNA repair, including xeroderma pigmentosum, trichothiodystrophy, Cockayne syndrome, and Bloom syndrome. Early diagnosis may prevent complications associated with prolonged unprotected exposure to sunlight and makes it possible to offer genetic counseling and, when indicated, prenatal diagnosis to families at risk for these rare heritable disorders.

Photosensitivity skin disorders in childhood

“…In addition to the laboratory tests, routine histology and electron microscopic examination of the liver of our young patients were performed in 1967, which revealed mitochondrial alterations and other ultrastructural changes suggesting the role of the liver in the pathomechanism of EPP (37, 38). The prophylactic possibilities include broad‐spectrum sunscreens, oral β‐carotene with moderate effect (39), and recently narrow‐band UVB phototherapy (40). Gene therapy should become possible in the future.…”

“…Genophotodermatoses (31, 39) with different kinds of genetic defects in the UV repair processes (XP, Cockayne's syndrome, trichothiodystrophy, etc.) or with other biochemical abnormalities (Smith–Lemli–Opitz syndrome, Hartnup disease, etc.)…”

Malignant epithelial tumors: Part I. Pathophysiology and clinical features

“…XP patients have a 10 4 ‐fold increased risk of development of, among others, KT with a median age of initial manifestation of 9 years. When a small child develops lentiginosis in sun‐exposed skin, one should think of XP [22]. In a subgroup of XP neurological disturbances such as weakened deep muscle reflexes as well as neurogenic hearing loss develop.…”

Photodermatoses

“…While electromagnetic radiation is the critical pathogenic factor with primary photodermatoses, secondary heliotropic diseases have another genesis altogether, although they are also induced by sunlight. Secondary photodermatoses are frequently a feature of systemic diseases such as lupus erythematosus, metabolic disorders such as porphyrias, or disorders of DNA repair such as xeroderma pigmentosum (3).…”