Feline Leprosy due to Infection with novel Mycobacterial Species

An eleven-year-old, FIV-negative, castrated Persian cat was presented with multiple subcutaneous nodules. A provisional diagnosis of feline leprosy was made based on the presence of abundant bacilli within macrophages on Diff-Quik stained smears from aspirates of a nodule. The organism was identified subsequently as a novel species of mycobacterium using 16S rRNA PCR and direct sequence analysis. Effective treatment was achieved by surgically resecting the largest lesions and using triple therapy with clofazimine, clarithromycin and ciprofloxacin. This report adds to the growing body of evidence that feline leprosy is a treatable clinical syndrome caused by potentially pathogenic saprophytic mycobacteria including M. lepraemurium, M. avium and other as yet uncharacterised mycobacterial species.