Cutaneous signs of internal disease -- congenital, parasitic, drug related, neoplastic, or endocrine diseases

摘要

Congenital/hereditary dermatoses: These diseases are present at birth or noted shortly thereafter. Affected animals should not be bred. Dermatomyositis: This disease has been reported primarily in collies and Shetland sheepdogs and their crosses, although other breeds have a sporadic incidence of this disease. As its name implies, the disease affects both the muscles and the skin. Cutaneous changes include crusts, ulcerations, vesicles, and/or alopecia around the mucocutaneous junctions, front legs, ear tips, and tail, though other body areas may be affected. Muscular atrophy may be generalized or may be selective, often affecting the temporal and masseter muscles. Clinical manifestations vary, with some dogs showing only skin or muscular signs, while in others both systems are affected. Serum enzymes such as creatinine phosphokinase (CPK) are usually normal, and muscle involvement often may be proved only by biopsy or electromyograpby. Skin biopsies generally reveal perifollicular mononuclear inflammation, and occasionally show intracellular edema of the basal cell layer of the epidermis, with subepidermal clefts; advanced cases show a loss of the normal follicular structures. The onset of clinical signs usually occurs before the age of 6 months. The severity of the disease varies greatly, with some dogs improving with age. Females should be spayed as estrus may exacerbate clinical signs. Pentoxifylline, 10-20 mg/kg q8h, is often effective in controlling the disease. Vomiting is occasionally seen as a side-effect.