Characterization phenotype, genotype and of factor of virulence in strains of the genus Nocardia isolation of bovine mastitis, diseases of animal company and human patients with and without immunosuppression, involvement of nocardiosis

Abstract

The aerobic actinomycetes comprise a complex bacterial group. Rhodococcus, Nocardia and Corynebacterium genera are more pathogenic to animals and humans. Nocardia genus is characterized by piogranulomatous lesions of chronic evolution. The Nocardia sp comprises ubiquitous microorganisms found in soil, plants and water. In recent years, nocardiosis has been considered as an emerging disease to humans and animals in worldwide. Atypical clinical manifestations of the organism, microbiological and clinical similarity with other actinomycetes, have probably results in poor diagnosis of the disease. The pathogenicity of the genus Nocardia is attributed to intracellular localization of the organism in phagocytes, the induction of piogranulomatous reactions, antimicrobial resistance, and the opportunistic behavior of the bacteria, exacerbated in immunosuppressed patients. Among the pathogenic species and higher frequency of infection in humans and animals deserve emphasis: Nocardia asteroides type I, II, III, IV, V and VI, Nocardia brasiliensis, Nocardia pseudobrasiliensis, Nocardia transvalensis and otitidiscaviarum. The present study aims to characterize the main pheno and genotypic aspects, and virulence factors in strains of the genus Nocardia isolated from bovine mastitis, different diseases in companion animals and human patients, with and without immunosuppression, affected by nocardiosis. (AU)