First Case Report of Successful Treatment of Mycobacterium abscessus Infection in a Cat in Thailand

A female domestic shorthair cat aged 2 years was referred with a 1-month history of subcutaneous nodules and multiple sites of draining tracts at the ventral abdomen. Initially, the cat was diagnosed with a fungal infection and treated with oral itraconazole, without improvement. Comprehensive diagnostics, including cytology, which indicated pyogranulomatous inflammation, fungal culture that was negative, and bacterial culture, confirmed the presence of <i>Mycobacterium abscessus</i>. This infection was treated with a combination of oral azithromycin and topical amikacin based on susceptibility testing; later, doxycycline and an immunostimulant supplemented were combined at day 36 of treatment due to mild improvement of the lesions. The cat showed gradual improvement, achieving complete resolution of the lesions after 14 weeks, with no relapse noted 24 weeks post-treatment. This case report demonstrates the diagnostic challenges and the necessity for tailored, multi-drug therapeutic approaches in managing mycobacterial infections in cats. The findings may guide future treatments and raise awareness of mycobacterial diseases in cats.