Instituto Valenciano de Microbiología
(IVAMI)

Masía El Romeral
Ctra. de Bétera a San Antonio Km. 0.3
46117 Bétera (Valencia)
Phone. 96 169 17 02
Fax 96 169 16 37
Email: 
www.ivami.com
CIF B-96337217

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Bullous ichthyosiform erythroderma; Epidermolytic hyperkeratosis (Epidermolytic hyperkeratosis; Bullous erythroderma ichthyosiforme) - Genes KRT1 or KRT10.

The Epidermolytic hyperkeratosis, also known as ichthyosiform erythroderma bullosa is a skin disorder that manifests at birth. Affected infants may present erythroderma and severe blisters. Because newborns lose the protection afforded by normal skin, they are at risk of becoming dehydrated and develop sepsis. As these individuals get older, blistering is less frequent, the eritrodermia becomes less evident and the skin becomes hyperkeratotic, especially in the joint areas, in the areas of skin friction, or scalp or neck. This thickening of the skin is usually darker than normal. Bacteria can grow in thick skin, often producing a distinct odor.

The Epidermolytic hyperkeratosis can be classified into two types. People with type PS Epidermolytic hiperqueratosis have thick skin on the palms and soles of the feet, as well as in other areas of the body. People with the other, the NPS type, have palmoplantar hyperkeratosis hyperkeratosis but present in other areas. Epidermolytic hyperkeratosis is the part of a group of diseases called ichthyosis. However, epidermolytic hyperkeratosis in the skin is thick but not flaky and some of the other alterations group.

This process is due to mutations in genes KRT1, located on the long arm of chromosome 12 (12q13.13), and KRT10, located on the long arm of chromosome 17 (17q21). These genes encode proteins called keratin 1 and keratin 10, which are in the epidermal keratinocytes. Keratin proteins, stick together constituting intermediate filaments, which provide strength and resistance to the epidermis.

They have identified dozens of mutations in the gene KRT1 and the KRT10 gene in people with Epidermolytic hyperkeratosis. Mutations in genes KRT10 KRT1 or cause changes in keratin proteins, which inhibits the formation of networks resistant and stable within cells intermediate filaments. Without a strong network, keratinocytes become fragile and easily damaged, which can lead to blistering in response to friction or minor trauma. It is unclear how these mutations cause overgrowth of epidermal cells which results in hyperkeratotic skin. Mutations in the gene KRT1 associated with PS type epidermal hyperkeratosis, and mutations in the gene KRT10 are usually associated with the type NPS. Keratin protein 1 is present on keratinocytes from the skin of the palms and soles and other parts of the body, so that mutations in the KRT1 gene lead to skin problems in these areas. 10 keratin protein not found in the skin of palms and soles, so that these areas are not affected by mutations in the gene KRT10.

The Epidermolytic hyperkeratosis may have different patterns of inheritance. About half of the cases are caused by new mutations in the KRT1 or KRT10 gene and occur in people with no history of disease in your family. Epidermolytic hyperkeratosis When inherited, it is usually an autosomal dominant pattern, which means that a copy of the altered gene in each cell is sufficient for alteration is expressed. Rarely, when the disease is due to mutations in the gene KRT10 it can be inherited with an autosomal recessive pattern, which means that both copies of the gene in every cell must have mutations for alteration is expressed. The parents of an individual with an autosomal recessive disease have a copy of the mutated gene, but usually show no signs and symptoms of the disease.

Tests in IVAMI: in IVAMI perform detection of mutations associated with epidermolytic hyperkeratosis or bullous ichthyosiform erythroderma, by complete PCR amplification of the exons of KRT1 and KRT10, respectively, genes and subsequent sequencing.

Samples recommended: EDTA blood collected for separation of blood leukocytes, or impregnated sample card with dried blood (IVAMI may mail the card to deposit the blood sample).