PATOLOGIE INFIAMMATORIE CRONICHE CUTANEE E MUCOSALI NELLA SPECIE FELINA (PATOGENESI E RUOLO DI ANTIGENI EZIOLOGICI VIRALI).

Feline chronic and recurrent inflammatory and mucocutaneous diseases represent a frustrating problem in veterinary clinical practice. These diseases such as ulcerative and allergic dermatides, feline lymphoplasmacytic chronic gingivostomatitis, rhinitis and pododermatitis recur frequently have a poor therapeutic response, have often an unknown etiology, have been poorly characterized pathogenically and may demonstrate progression to neoplasia. The aim of this study was to analyze some aspects of the etiology (viral antigen component), the histopatological aspects of ulcerative dermatides with eosinophilic component and the role of feline herpes virus 1. The role of viral antigens and type of plasma cell population present in feline lymphoplasmacytic gingivostomatitis and to better characterize the lesions of the linear presentation of feline eosinophilic granuloma complex. Ulcerative eosinophilic dermatitis is common in cats however the forms associated with feline herpes virus 1 seem uncommon. The disease is characterized by cutaneous ulcers secondary to epidermal, adnexal and dermal necrosis. Differential diagnoses for feline ulcerative and eosinophilic dermatitis include for FHV-1 lesions, mosquito bite hypersensitivity and eosinophilic granuloma complex. Histopathological diagnosis of FHV-1 dermatitis is based on the detection of the intranuclear inclusion bodies. In cases where intranuclear inclusions are missing (eg. severe necrosis, chronic or recurrent cases) but clinical and histological findings are compatible with FHV-1 dermatitis, IHC and PCRs were applied and results were compared. Our main results was that when clinical signs and histopathology suggest FHV-1 infection in the absence of typical inclusion bodies, IHC should be the preferred diagnostic test; PCR may be useful for initial screening, but due to false positives is not sufficient for a definitive diagnosis. This is due to the presence in latency of the virus in previously infected cats. Feline gingivostomatitis is a common disease in cats; many viral, bacterial, allergic, immunoresponsive alteration have been implicated in the disease. We evaluated the presence of antigens of Feline leukemia virus, the persistence of Feline Calicivirus, the type of plasmacells (IgG, IgM, IgA) and the possible transformation of plasmacells during the chronic process by evaluation of Ki67 (proliferation index) and clonality. Surprisingly, the majority of cases had IgG plasmacells that demonstrate to proliferate and in some instances to represent a clonal proliferation. Feline eosinophilic granuloma is a common, clinically heterogeneous syndrome affecting skin, mucocutaneous junctions and oral mucosa: clinical presentation are unified by a similar histopatological pattern. The lesions have been subdivided clinically according with presentation and lesion location. The most common cutaneous presentation is linear granuloma. In this form distinctive, hairless, well circumscribed, firm, pink red elevated plaques develop in a strikingly linear pattern on the caudal thighs, forelegs or less commonly the neck or thorax. We evaluated the histological inflammatory process and identified vessel walls by immunohistochemistry (Factor VIII and CD31). Histology demonstrate that the linear pattern may be the consequence of the inflammation associated not only to the connective tissue but with the vessel walls representing most likely a lymphangitis.