Vesiculobullous skin reaction temporally related to firocoxib treatment in a white rhinoceros (Ceratotherium simum).

A 40 yr-old female white rhinoceros (Ceratotherium simum) suffered from chronic nail-bed abscesses. Due to worsening of clinical signs, the animal's nonsteroidal anti-inflammatory treatment was switched to firocoxib. Approximately 7 days after this change, the animal developed multifocal vesicles and bullae along the lateral aspects of the thorax and abdomen, the dorsum, and the proximal limbs. Cytology and culture did not identify an infectious etiology. Histologically, the lesions consisted of a severe, subacute vesiculobullous dermatitis with intraepidermal to subepidermal clefting with areas of individual keratinocyte necrosis and minor neutrophilic epidermal infiltrates. These findings are similar to those seen in some drug reactions in people; therefore an adverse drug reaction to the firocoxib was suspected.

Clinical and immunological heterogeneity of canine subepidermal blistering dermatoses with anti-laminin-332 (laminin-5) auto-antibodies.

Laminin-332 (laminin-5) is a basement membrane heterotrimeric protein composed of alpha-3, beta-3 and gamma-2 laminin chains. Laminin-332 polypeptides are targeted by auto-antibodies in human patients with mucous membrane (cicatricial) pemphigoid or, more rarely, subepidermal vesicular diseases that resemble epidermolysis bullosa acquisita (EBA) or bullous pemphigoid (BP). The objectives of this report were to characterize the clinical, histopathological and immunological characteristics of nine dogs with auto-antibodies targeting laminin-332. Immunological investigations consisted of direct immunofluorescence (IF), indirect IF with intact and salt-split canine gingival, and salt-split normal or laminin-332-deficient human skin, immunoblotting with purified human laminin-332 and immunoblotting with recombinant NC1 domain of human collagen VII. All dogs exhibited varying degrees of skin blistering and ulceration associated with microscopic subepidermal vesiculation with or without inflammatory cells. Indirect IF established that circulating IgG auto-antibodies bound the dermal side of salt-split canine lip and human skin. In five dogs, IgG variably recognized the basement membrane of laminin-332-deficient human skin (three dogs negative, two dogs positive). In all nine dogs, IgG auto-antibodies detected purified human laminin-332 by immunoblotting. In two dogs, additional targeting of collagen VII-NC1 was present. These observations establish laminin-332 as a novel basement membrane antigen in dogs with autoimmune blistering diseases with variable clinical phenotypes. The names 'acquired junctional epidermolysis bullosa', 'anti-laminin-332 mucous membrane pemphigoid (MMP)' and 'mixed auto-immune subepidermal blistering dermatosis' are proposed for dogs with clinical signs reminiscent of EBA, MMP or BP respectively.

Papular urticaria: A review of causal agents in Colombia.

Papular urticaria is a chronic allergic reaction induced by insect bites, which is common in the tropics. The objective of this review was to deepen on epidemiological and immunological aspects of this disease, focused on data published in Latin American countries.We conducted a non-systematic review of the literature through electronic search on the epidemiology of papular urticaria, the entomological characteristics of the causative agents and associated immunological mechanisms.Several reports from medical centers suggest that papular urticaria is common in Latin America. Only one epidemiological survey designed to estimate prevalence of papular urticaria has been published, reporting that about a quarter of children under six years of age is affected by this condition in Bogotá. There is evidence on the causal relationship among exposure to indoor fleas, poverty and papular urticaria in Bogotá, a representative city of the Andean altitudes. Information about causal insects in tropical warmer areas is scarce, although from clinical reports Aedes aegypti and Culex quienquefasciatus appear to be the most common. Th2 cellular-mediated mechanisms are involved in its pathogenesis, which explains its delayed hypersensitivity. The role of immunoglobulin E is not clear in this disease. Insect-derived antigens directly involved in papular urticaria etiology are unknown. However, it is possible that common molecules among causal insects mediate cross-reactive reactions, such as Cte f 2 allergen, found in cat fleas, and its counterparts in mosquitoes.Papular urticaria is a frequent disease in Latin America that should be further investigated. Immunological characterization of the molecular components that cause this condition may solve questions about its pathogenesis.

Effect of substrate selection on indirect immunofluorescence testing of canine autoimmune subepidermal blistering diseases.

The detection by indirect immunofluorescence (IIF) of circulating antibodies in the serum of dogs with autoimmune subepidermal blistering diseases (AISBD) was regarded for a long time as an unrewarding tool. It was, however, demonstrated in humans that the sensitivity of IIF assays depended on the selection of the substrates used. The effects of substrate selection on IIF tests was thus studied by examining sera from 12 dogs with AISBD tested against 8 different substrates from 3 different normal dogs. Patients with AISBD suffered from bullous pemphigoid (n = 4 sera), mucous membrane pemphigoid (n = 4 sera), and epidermolysis bullosa acquisita (n = 4 sera). Substrates included canine tongue, canine lip, canine dorsal haired skin, and ventral haired skin. The same 4 substrates were also split with salt splitting technique (using 1 M sodium chloride), in order to cleave the basement membrane within the lamina lucida and to expose the targeted antigens. The strength of the specific fluorescence of each slide was scored after processing for IIF testing with anti-canine IgG polyclonal antibody. Other criteria, such as background fluorescence, easiness of the interpretation, and variations within a same substrate, were also assessed. Intact canine lip and canine salt-split lip demonstrated consistently stronger intensity of fluorescence and a better ease of interpretation. We concluded that the performance of IIF tests with such substrates was a reliable tool for the detection of circulating IgG autoantibodies of canine patients with AISBD.

Isolation of bovine herpesvirus-1 from vesicular lesions of the bovine udder.

Bovine herpesvirus-1 was isolated from vesicular lesions on the udder and mammary papillae (teats) of a Charolais cow. Lesions on the animal consisted of papules and vesicles up to 10 mm in diameter. The virus was identified by fluorescent antibody and serum-neutralization tests.

Skin pustules and nodules caused by Actinomyces viscosus in a horse.

A 12-year-old Arabian stallion was evaluated for a refractory skin problem of 2 years' duration. Skin nodules and pustules, which would rupture, had developed over the right lumbar muscles. Anaerobic culturing from the pustules yielded Actinomyces viscosus, and histologic examination of biopsy specimens revealed globular eosinophilic structures. Concomitant treatment with isoniazid (8 mg/kg of body weight, q 24 h for 8 weeks), trimethoprim-sulfadiazine (30 mg/kg, q 24 h for 8 weeks), and sodium iodide solution (66 mg/kg, every 1, 2, or 4 weeks, for 32 weeks) resolved the condition.

Bullous pemphigoid refractory to recommended dosage of prednisolone in a dog.

Bullous pemphigoid in a dog was diagnosed on the basis of clinical, histopathologic, and immunologic criteria. There were widespread ulcerative lesions of the skin. Numerous ulcerative lesions and occasional bullous lesions were on the oral mucous membranes. Histopathologic changes included dermal-epidermal separation, with subepidermal production of bullae. Direct immunofluorescent staining of the skin revealed depositions of immunoglobulin G and of the 3rd component of the complement system. Indirect immunofluorescent staining of donor skin sections pretreated with patient's serum revealed antibasement membrane antibody in the patient's serum. Most of the data in the serum immune profile were within normal ranges. Prednisolone therapy did not effect remission at the dosage of 4.4 mg/kg/day, but led to the beginning of remission within 7 days at a dosage of 6.6 mg/kg/day. The dosage was gradually reduced to 1.1 mg/kg, at 30 days, after which the drug was given on alternate days at that dosage. The healing was complete within 35 days, without any remissions when the dog was last examined (ie, over 6 months).

Immunofluorescence testing in a bullous skin disease of a dog.

A chronic skin disease in a dog, which resembled a pemphigus-like condition, was studied histologically and by direct immunofluorescence testing. Histologic examination revealed a bullous disorder and was a useful diagnostic tool; however, direct immunofluorescence testing showed the disease to be equivalent to bullous pemphigoid of man.

Outbreak of vesicular dermatitis among horses at a midwestern horse show.

Dermatitis consisting of blisters on the nose and other parts of the body was reported among horses at a Midwestern horse show. Some horses also had jaundice, hematuria and anorexia. An outbreak investigation was initiated, and of 239 horses for which information could be obtained, 58 (24%) were found to have been affected. Median duration of illness was 5 days, and all horses recovered. Age, sex, water source, grain source, and stabling location were not associated with illness. The use of wood shavings bedding obtained at the show grounds was the factor most strongly associated with the development of vesicular lesions. Horses that became ill were 43 times more likely to have been bedded on wood shavings obtained from the show grounds than were horses that did not become ill. Among horses bedded on shavings from the show grounds, the risk was further increased by a factor of 5 if the shavings had been wetted. Neither organic nor heavy metal toxicants were identified in the samples of the wood shavings. However, samples did contain plant tissues originating from a tree belonging to the family Simaroubaceae, some species of which are known to cause vesicular eruptions in people.

Observations of the immunopathology and therapy of canine pemphigus and pemphigoid.

Immunopathologic evaluation of 27 dogs with pemphigus and pemphigoid demonstrated that direct immunofluorescence testing was vastly superior to indirect immunofluorescence testing for diagnosis. Therapeutic studies in 31 dogs with pemphigus and pemphigoid demonstrated that glucocorticoids given for systemic effect were unsatisfactory as the sole form of treatment because of lack of efficacy of unacceptable side effects, or both, in over 50% of the cases.

Allergic- and immunologic-mediated diseases of the eye and adnexae.

Significant allergic- and immunologic-mediated diseases of the eye are reviewed. Included are diseases of the lacrimal gland namely keratoconjunctivitis sicca, immune-mediated diseases of the conjunctiva, atopic blepharoconjunctivitis, and marginal blepharitis, uveitis including lens-induced uveitis, episcleritis, orbital cellulitis, and optic neuritis. Significant diagnostic features, an approach to diagnostic workup, and treatment are presented.

Bullous autoimmune skin disease in the dog: (1) clinical and pathological assessment.

The clinical and pathological findings of two cases of pemphigus vulgaris and four cases of bullous pemphigoid in the dog are reported. Clinically these cases were typified by ulcerative lesions of the oral mucous membranes, mucocutaneous junctions and skin. Pathologically there were intraepithelial separation and bulla formation in one of the cases of pemphigus and subepithelial separation and bulla formation in all cases of pemphigoid.

Bullous autoimmune skin disease in the dog: (2) immunopathological assessment.

The immunological examinations of two cases of pemphigus vulgaris and four cases of bullous pemphigoid in the dog are reported. Deposits of immunoglobulin and complement were identified betweeen epithelial cells of the pemphigus cases and at the epithelial/connectivce tissue junction in the pemphigoid dogs. The bullous autoimmune diseases must be considered in the differential diagnosis of mucosal and skin ulceration in the dog.

Bullous systemic lupus erythematosus (type I) in a dog.

In human patients with systemic lupus erythematosus, cutaneous subepidermal blistering can occur because of the production of antibodies specific for basement membrane antigens. This condition is referred to as bullous systemic lupus erythematosus (BSLE). A dog was diagnosed with BSLE because it fulfilled the following criteria: (i) a diagnosis of systemic lupus erythematosus by standard methods; (ii) an acquired, vesicular, erosive and ulcerative eruption; (iii) microscopical subepidermal vesicles with neutrophil-predominant inflammation at the dermo-epidermal junction; (iv) deposition of IgG at the epidermal basement membrane zone; and (v) circulating IgG autoantibodies against type VII collagen. Anti-collagen VII type I-BSLE therefore needs to be considered as a possible differential diagnosis for canine autoimmune subepidermal blistering diseases.

Impairment of neutrophil functions in a dog with an eosinophilic dermatosis.

An eosinophilic dermatosis was diagnosed in a dog with a multifocal distribution of pruritic, pustular and erosive lesions on the trunk. Ectoparasites, fungi and bacteria were not detected in the skin of the dog. At a subsequent admission to the university clinic, bacterial conjunctivitis and superficial pyoderma had developed. At a time when the dog received no medical therapy, evaluation of phagocytosis and chemotactic migration towards a variety of chemotactic factors revealed a general suppression of patient neutrophil responsiveness, as compared to a control dog. Viability of the patient's neutrophils was normal. It was proposed that deactivation of neutrophil functions occurred following exposure to suppressive factors from mast cells, or as a consequence of surface receptor down-regulation due to prolonged cell activation by as yet unknown stimulants. The observed susceptibility to infections in the dog suffering from a primary, sterile eosinophilic dermatosis may be related to impaired host defence against opportunistic microorganisms.

Diagnosing new autoimmune blistering skin diseases of dogs and cats.

Autoimmune blistering skin diseases have been recognized for decades in humans and dogs. In the dog, most of these diseases unfortunately were grouped under the generic denomination of bullous pemphigoid without any confirmation that the autoantibodies targeted bullous pemphigoid antigens. In recent years, advanced diagnostic methods have permitted the recognition of new autoimmune blistering skin diseases in humans and companion-animal species. At this time, the diagnosis of these entities is made by combining clinical signs and results of histopathology. Immunologic methods serve to establish the presence of skin-fixed and circulating autoantibodies that target various epidermal or basement membrane antigens. In this article, salient features of the most common canine and feline subepidermal blistering dermatoses (mucous membrane pemphigold, bullous pemphigold, epidermolysis bullosa acquisita) and new variants of cutaneous lupus (type I bullous systemic lupus erythematosus and vesicular cutaneous lupus erythematosus) are presented.

Obesity in a dog, with secondary hormonal imbalance.

Obesity in dogs is frequently encountered by veterinarians. The history, clinical and laboratory findings of an overweight dog are described. Overfeeding of an all-meat diet resulted in obesity, and subclinical nutritional secondary hyperparathyroidism. The obesity caused fatigue, decreased cardiac performance, respiratory embarrassment, skin lesions, prediabetes and increased glucocorticoid level. A balanced diet fed in limited amounts, and exercise, resulted in a marked loss of weight and an improvement in the dog's health. The practical control of canine obesity is discussed.