Clinical and morphological changes associated with eosinophilic syndrome in cats
Abstract
Eosinophilic syndrome in domestic cats (eosinophilic granuloma complex – EGC) has a complicated pathogenesis, and its manifestations significantly depend on the individual’s sensitivity, the type and multifactorial nature of the allergen, as well as the severity of the chronic condition. This study presents the results of a comprehensive analysis of the clinical, haematological, and cytological features of eosinophilic syndrome in cats with eosinophilic granuloma complex. The course of various clinical forms of this pathology was studied, which depends on the duration of the disease, the time taken for the pet owner to consult a veter i narian and receive treatment, and the identification of potential etiological factors; a morphological blood analysis was conducted, and lesions on the skin and mucous membranes were examined. It was established that clinical symptoms ranged from localised granulomatous lesions on the lips, in the oral cavity to generalised skin and mucous membrane lesions with the development of eosinophilic gastroenteritis, accompanied by appropriate changes in the white blood cell formula: from mild eosinophilia to hypereosinophilia (8–59%). Cytological examination revealed a prevalence of eosinophils, the presence of degenerated collagen fibres, frothy macrophages and fibroblasts, with no signs of microorganisms. Numerous neutrophils, foamy macrophages with phagocytosed collagen fragments, and small lymphocytes indicated active inflammation, tissue degradation, and chronicity of the lesion. Fibrocytes and isolated fibroblasts reflected tissue remodelling, while fragmented collagen fibres suggested destruction associated with eosinophil degranulation. Haematological analysis showed an increase in the number of erythrocytes and leuk o cytes, as well as in haemoglobin levels, in the affected cats. The findings confirm the allergic etiology of feline eosinophilic gra n uloma complex and the importance of a comprehensive diagnostic approach comprising clinical, haematological, and cytological methods.References
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