Clinical outcome of cutaneous rapidly growing mycobacterial infections in cats in the south-eastern United States: a review of 10 cases (1996-2006)

Cutaneous infection caused by rapidly growing mycobacteria is a relatively uncommon condition in cats, with variable response rates to surgical debulking and aggressive antibiotic therapy. To date, there have been very few case reports of this disease, especially in the United States. This study reviews a series of cases of cats with rapidly growing cutaneous mycobacterial infections from the south-eastern United States. A majority of the cats were spayed female domestic shorthairs. The median age at onset of clinical signs was 8 years. A majority of cats presented with characteristic lesions in multiple locations, and half of the cats had a known incidence of trauma preceding the development of clinical signs. Mycobacterium fortuitum was the most frequently cultured organism. Cats were treated with a variety of antibiotics for a median of 12 months, and half of them underwent surgical debulking of infected tissue. Five out of the 10 cats reached clinical resolution, while five did not. Those that did resolve required a median of 7 months of antibiotic treatment following diagnosis, and had been lesion-free for a median of 24 months at the time this study was completed. Those that did not resolve were treated for a median of 20 months following diagnosis, two of which were still being treated at the time this study was completed.