Whole exome sequencing in a sample of Peruvian patients diagnosed with epidermolysis bullosa.

BACKGROUND: Epidermolysis bullosa (EB) is a complex and heterogeneous dermatological disease. Four main types of EB have been described, each of them with distinct characteristics: EB simplex (EBS), dystrophic EB (DEB), junctional EB (JEB) and Kindler EB (KEB). Each main type varies in its manifestations, severity, and genetic abnormality. METHODS: We sought mutations in 19 genes known to cause EB and 10 genes associated with other dermatologic diseases in 35 Peruvian pediatric patients of a rich Amerindian genetic background. Whole exome sequencing and bioinformatics analysis was performed. RESULTS: Thirty-four of 35 families revealed an EB mutation. Dystrophic EB was the most frequently diagnosed type, with 19 (56%) patients, followed by EBS (35%), JEB (6%), and KEB (3%). We found 37 mutations in seven genes; 27 (73%) were missense mutations; 22 (59%) were novel mutations. Five cases changed their initial diagnosis of EBS. Four were reclassified as DEB and one as JEB. Inspection into other non-EB genes revealed a variant, c.7130C>A, in the gene FLGR2, which was present in 31 of the 34 patients (91%). CONCLUSION: We were able to confirm and identify pathological mutations in 34 of 35 patients.

Epidermolysis bullosa in animals: a review.

Epidermolysis bullosa (EB) is a hereditary mechanobullous disease of animals and humans, characterized by an extreme fragility of the skin and mucous membranes. The main feature of EB in humans and animals is the formation of blisters and erosions in response to minor mechanical trauma. Epidermolysis bullosa is caused by mutations in the genes that code for structural proteins of the cytoskeleton of the basal keratinocytes or of the basement membrane zone. Based on the ultrastructural levels of tissue separation, EB is divided into the following three broad categories: epidermolysis bullosa simplex, junctional epidermolysis bullosa and dystrophic epidermolysis bullosa. Human types of EB are divided into several subtypes based on their ultrastructural changes and the mode of inheritance; subtypes are not fully established in animals. In humans, it is estimated that EB affects one in 17,000 live births; the frequency of EB in different animals species is not known. In all animal species, except in buffalo with epidermolysis bullosa simplex, multifocal ulcers are observed on the gums, hard and soft palates, mucosa of the lips, cheek mucosa and dorsum of the tongue. Dystrophic or absent nails, a frequent sign seen in human patients with EB, corresponds to the deformities and sloughing of the hooves in ungulates and to dystrophy or atrophy of the claws in dogs and cats. This review covers aspects of the molecular biology, diagnosis, classification, clinical signs and pathology of EB reported in animals.

Junctional epidermolysis bullosa in a calf.

A case of epidermolysis bullosa in a calf descendent from a Gir bull and a Gir crossbreed cow is reported. The calf presented with exungulation of all hooves, widespread erosions and crusts on the skin, and ulcers in the oral cavity. Histologically, the skin showed subepidermal separation with clefts occasionally filled with eosinophilic clear fluid, cellular debris, or neutrophils. Ultrastructurally, there was epidermal-dermal separation at the level of the lamina lucida, with the lamina densa attached to the papillary dermis. The hemidesmosomes were poorly defined and small. The clinical, histological, and ultrastructural findings are characteristic of junctional epidermolysis bullosa.

Epidermólise bolhosa distrófica e juncional: aspectos gastrointestinais / Epidermolysis bullosa, dystrophic and junctional type: gastrointestinal aspects

Objetivo: avaliar os distúrbios gastrointestinais de crianças e adolescentes com epidermólise bolhosa do tipo distrófica e juncional. Métodos: foram analisados os sinais e sintomas gastrointestinais presentes no primeiro atendimento, assim como os resultados de exames, de todosos pacientes atendidos com a doença em uma unidade universitária de gastroenterologia pediátrica / Objective: to evaluate the gastrointestinal disturbances observed in patientss with epidermolysis bullosa, junctional and dystrophic type. Methods: the gastrointestinal complaints at the first consultation were analysis...

Alteraciones de la zona de membrana basal en enfermedades cutáneas / Abnormalities of the basement membrane zone in cutaneous diseases

Diversas enfermedades cutáneas se caracterizan por alteraciones localizadas preferentemente en la zona de membrana basal. Estas dermatosis se han hereditarias y adquiridas. Se pueden encontrar cambios ultraestructurales en la membrana basal, muchos de los cuales serían causados por fenómenos autoinmunes. Múltiples investigaciones han permitido aclarar la morfogénesis de las lesiones clínicamente visibles que afectan esta zona en particular. En la presente revisión se realiza una puesta al día de la última información de la literatura sobre estas interesantes enfermedades