Mycobacterial disease in the cat

MYCOBACTERIA are a large heterogeneous group of organisms, most of which are saprophytic and usually non-pathogenic. Several species can cause disease in cats, being either primary pathogens, or becoming pathogenic in certain circumstances. Mycobacterial syndromes seen in cats include classical tuberculosis, feline leprosy and opportunistic mycobacteriosis. All have been reported in the UK, where the majority of cases appear to be cutaneous in nature. All three syndromes can present with nodules, draining tracts and/or ulceration. In some cases, the disease may become generalised secondary to skin inoculation, but only occasional cases present with primary systemic disease. Where systemic disease is seen, infection with a member of the tuberculosis group is most likely. In many cases of feline mycobacteriosis, infection can be related to percutaneous injury, contamination via soil or the presence of devitalised tissue, and these factors tend to be reflected in the distribution of the lesions.