You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Non-pathogenic mycobacteria can become involved in superficial skin wounds and may require treatment

Although they are not pathogens, saprophytic mycobacteria (which are commonly found in the environment - especially soil) can become involved in superficial skin wounds resulting in a chronic lesion in the form of an abscess, ulcer or granuloma. These organisms are easily recognised by experienced laboratory technicians on examination of tissue biopsies or swabs/cultures, but they may be missed or misinterpreted by inexperienced technicians.

The following have been reported to have occurred  in cat and dog lesions :

• Mycobacterium fortuitum and M.chelonei complex
• M.phlei 
• M.smegmatis
• M.xenopia

Treatment involves:

•  Surgical excision of the affected area,

 and medication with :

• Gentamicin - 2mg/kg body weight  by injection (intramuscular or subcutaneous)  twice a day, OR
• Potentiated sulphonamides - 10-15mg/kg body weight by mouth twice daily 
• NOW combined antimicrobial treatment is advised : egs clarihromycin, and rifamicin but these may not be licensed for veterinary use.

The prognosis is good in most cases.

Refernce 

Malik R (2004) Mycobacterial diseases affecting the skin or subcutis of cats and dogs Veterinary Dermatology 15:s1 p16

Updated October 2013