[A new treatment possibility for dogs with chronic or recurrent pyoderma].

Abstract

Effective treatment of chronic or recurrent pyodermas in dogs is often found to be difficult. The disease apparently results from a change in the balance between the infecting microorganism: Staphylococcus aureus, and the host. This change in the normal equilibrium could be due to enhanced virulence of the infecting strain of staphylococci, but is more likely to have been caused by host factors such as disturbed non-specific defence mechanisms (of the skin) or malfunction of the immune response, e.g. hypersensitivity. When conventional forms of treatment such as grooming, skin-hygienic measures and antibiotics fail or relapses occur, immunotherapy with a staphylococcal vaccine or toxoid might be considered. In studies with experimental animals it was shown alpha-toxoid was superior to other staphylococcal toxoids or vaccines in preventing skin lesions. Four dogs with deep-seated chronic pyodermas were treated with staphylococcal alpha-toxoid emulsified in Freund's adjuvant. Three of these animals recovered, but because of severe unwanted side-effects, this form of therapy was abandoned. Ten dogs with deep-seated chronic primary pyodermas were treated with a commercially available alpha- and beta-toxoid preparation (Isopyos). Nine of these patients recovered. In two cases, however, relapses occurred several months later, but the symptoms disappeared again after a booster injection. One dog did not respond; its condition deteriorated and it had to be euthanised. As the dogs received toxoid intracutaneously as well as intramuscularly, the positive effect might be due to desensitization of the animals rather than to immunisation.