Epidermolysis bullosa in German black headed mutton sheep

In three flocks, 13 pure- and 1 crossbred German black headed mutton lambs were ascertained which had clinical signs of epidermolysis bullosa (EB). The three farmers reported of further 20 affected lambs with similar signs in their flocks in the past lambing seasons. The affected lambs were progeny of six rams and 17 ewes. Two rams and six ewes with affected offspring from two farms were used for a breeding trial. In the course of these experimental matings, 21 lambs were born, six of which were affected by EB. All lambs born in this trial underwent clinical and haematological examination and all the affected lambs had to be euthanised due to severe and progressing clinical symptoms. Clinical examinations in 20 affected lambs revealed shedding of claw horn, erosions and ulcers of skin and mucous membranes. Histopathology showed subepidermal splitting and blistering with intact basal keratinocytes. These findings together with the premature death of affected lambs within the first two months of life made a Herlitz type of junctional EB most likely. The results of the test matings demonstrated the genetic transmission and indicated an autosomal recessive mode of inheritance for this lethal condition.

Rudimentary hemidesmosome formation in congenital generalized junctional epidermolysis bullosa in the Sprague-Dawley rat

Seven of 14 newborn pups in a litter of Sprague-Dawley rats were found to have generalized detachment of the epidermis, which was thin, wrinkled, and hung in loose folds over distal extremities. Histologic and ultrastructural examination of the skin showed noninflammatory separation of the epidermis from the dermis at the lamina lucida of the basement membrane zone. Ultrastructurally, hemidesmosomes were small and had a rudimentary appearance; keratin tonofilaments in basal keratinocytes were detached from the hemidesmosomes. The skin lesions were consistent with generalized junctional epidermolysis bullosa, which has not previously been reported in the rat. In humans, generalized junctional epidermolysis bullosa is most commonly caused by autosomal recessive inheritance of defective proteins of the hemidesmosomes or anchoring filaments. The specific protein defect involved in the rat lesion was not determined because fresh frozen tissue was not available.

Immunomapping of basement membrane zone macromolecules in canine salt-split skin

Certain macromolecules of human and canine cutaneous basement membrane zone (BMZ) have shown to have responsibilities for pathogenesis of mechanobullous skin diseases. Salt-split skin by 1 M NaCl have been used for diagnosis of human mechanobullous diseases. However, there have been no studies to characterize canine salt-split skin. Electron microscopy of canine salt-split skin showed the separation within lamina lucida. Indirect immunofluorescence revealed the roof of the cleft was labeled by human patient serum with bullous pemphigoid, whereas laminin, laminin 5, type IV and type VII collagen were labeled at the bottom of the cleft. It is suggested that immunomapping of salt-split skin may be useful for the differential diagnosis of canine mechanobullous diseases.

[Epidermolysis bullosa in a calf]

A four-week-old Simmental x Red Holstein calf had lesions of skin and oral mucosa since its first days of life. Where skin or mucosa was exposed to minimal trauma as in oral cavity or over joints, it broke off, forming blisters and erosions. The diagnosis of epidermolysis bullosa, a hereditary disease, was based on clinical and histological findings. Histology pointed to the epidermal form of epidermolysis bullosa, comparable to epidermolysis bullosa simplex in humans.

Hereditary suprabasilar acantholytic mechanobullous dermatosis in buffaloes (Bubalus bubalis)

A skin disease characterized by trauma-induced sloughing of haired skin, hooves, and horns is described in four calves from a herd of Murrah buffaloes (Bubalus bubalis) in Brazil. Affected calves were detected shortly after birth by the presence of lesions affecting the distal extremities, the scapular and gluteal regions, and the tip of the tail. On histologic evaluation of affected skin, the lesions were characterized by suprabasilar vesicles and acantholysis affecting the epidermis and outer root sheath of the hair follicle infundibulum. The basal cell layer was intact and appeared as a single layer of cuboidal cells attached to the dermis. Ultrastructurally, the region between the stratum basale and the lower stratum spinosum had widened intercellular spaces with loss of desmosomal attachments, which led to the suprabasilar separation. The disease appears to be inherited as an autosomal recessive trait.

Congenital generalized epidermolysis bullosa in a calf

Epidermolysis bullosa is reported in a newborn calf. The disorder was lethal due to the large extension and severity of the skin lesions. Histopathologically, the defect was characterized by suprabasilar clefts located in stratum spinosum. In large areas, most epidermal layers were lost exposing stratum basale or even dermis. The basal membrane seemed normal. The disorder shared features with previous reported cases of both epidermolysis bullosa and familial acantholysis. The aetiology was not determined.

Hereditary junctional mechanobullous disease in a foal

Mechanobullous disease was diagnosed in a male Belgian foal that had sloughed hooves at 30 hours and at 6 and 12 days of age. Histologic and electron microscopic studies disclosed that lesions were the result of separation of the basal epithelial cell layer from the lamina densa of the basement membrane zone along the lamina lucida. Results of immunofluorescence on tissue specimens were negative for immunoglobulin deposition. The breeding history of the foal's dam indicated that the foal was produced from breeding of the mare to its full sibling stallion. This same mare had produced a female foal, sired by a different stallion, which also had sloughed hooves during the first 2 weeks of life and had similar histologic and electron microscopic changes. This newly recognized disease of horses most closely resembles junctional-type epidermolysis bullosa described in human beings.

Ultrastructure of junctional epidermolysis bullosa in Belgian foals

Ultrastructural examination of a mechanobullous disease of probable hereditary nature in Belgian foals, confirmed light microscopic findings that separation of the dermo-epidermal junction occurred through the lamina lucida of the basement membrane, leaving the intact lamina densa adherent to the dermis and the plasmalemma of the basal epithelial cells intact. The location of the cleft and the presence of small hemidesmosomes in adjacent intact skin are additional characteristics which make this condition similar to junctional epidermolysis bullosa of man.

A disease resembling junctional epidermolysis bullosa in a toy poodle

A disease resembling junctional epidermolysis bullosa in humans is described in a toy poodle. Shortly after birth, the affected animal developed vesicles and bullae on the pads of the feet and the mucous membranes of the oral cavity. The lesions rapidly increased in number and severity, eventually involving the glabrous skin of the ventral abdomen. Due to the severity of the lesions, the animal was euthanized when it was 48 h old. Histopathologic, ultrastructural and immunohistochemical evaluation defined a minimally inflamed subepidermal vesicular disease with separation occurring at the zona lucida of the basement membrane zone. Laminin and type IV collagen were present at the base of the vesicle.

A congenital bovine epidermolysis resembling epidermolysis bullosa simplex of man

Twenty-five of 72 calves sired by a Simmental bull were affected with a congenital skin disease which appeared to be inherited as an autosomal dominant trait. The affected calves showed hypotrichosis, erythema and breaks in the integrity of the skin. The distribution of the lesions and the ease with which excoriations occurred suggested an abnormal vulnerability to trauma. Mortality was high but in affected survivors the clinical signs moderated with age. Histopathologically, dermoepidermal separation and cytolysis of the germinal cell layer of the epidermis were seen. The name bovine epidermolysis is proposed and a relationship with epidermolysis bullosa simplex of man is suggested.

The comparative pathology of non-viral bullous skin diseases in domestic animals

In a review of non-viral bullous skin diseases of domestic animals and a 4-year study of cases presented to the New York State College of Veterinary Medicine, we found 15 diseases: pemphigus vulgaris, pemphigus vegetans, pemphigus foliaceus, pemphigus erythematosus, bullous pemphigoid, systemic lupus erythematosus, dermatitis herpetiformis, toxic epidermal necrolysis, drug eruption, epidermolysis bullosa, epidermolysis bullosa simplex, familial acantholysis, bovine congenital porphyria, impetigo and subcorneal pustular dermatosis. The 15 diseases were placed in five categories: autoimmune, immune-mediated, hereditary, bacterial and idiopathic. A histologic classification of these disorders based on the site of blister formation and other important clinicopathologic, histologic and immunopathologic findings was developed.

Epidermolysis bullosa simplex in the Collie dog

Epidermolysis bullosa simplex was diagnosed in 4 Collie dogs. Three of the dogs were less than 6 months old when lesions were first noticed. Lesions were characterized by alopecia, erythema, edema, erythematous plaques, erosions, ulcers, crusts, atrophy, pigmentary changes, and (rarely) blisters affecting the skin over bony prominences and joints of the limbs, face, lips, and ears. Minimal to moderate pruritus or pain was manifested by chewing and licking at the affected areas of the limbs and by pawing and rubbing at the face and ears. Lesions could be induced by frictional trauma in areas of normal skin. Diagnosis was confirmed by histologic examination of affected tissues and induced lesions. Therapy with large oral doses of prednisolone and avoidance of trauma were palliative.