Small Animal Dermatology, 3rd edition

CHAPTER 34 MYCOBACTERIAL INFECTIONS 515

THERAPEUTICS

 Tuberculosis:
Permission of local health authorities should be obtained in cases ofM. tubercu-

losisandM. bovisinfection due to their zoonotic potential

Multiple-agent chemotherapy with drugs used to treat human tuberculosis has

been successful

M. aviumcomplex infections are difficult to treat.

 Feline leprosy syndrome:
Before widespread dissemination, individual lesions may be excised with aggres-

sive margins, which may be curative

Surgical treatment should be preceded by systemic therapy.

 Canine leproid granuloma:
Excision is curative
Lesions may self-cure within 1–3 months
Antimicrobial therapy may assist healing.

 Systemic nontuberculous mycobacteriosis:
Treatment should be based on organism identification and antibiotic sensitivity

testing

Multiple drug therapy is often warranted

Aggressive surgical debulking may aid resolution; antimicrobial therapy pre- and

intraoperatively is recommended.

Drugs of Choice

 Tuberculosis:
Multiple drug oral therapy required; never attempt single-drug therapy
Current recommendation: fluoroquinolone with clarithromycin and rifampin for

6–9 months:

Fluoroquinolone: marbofloxacin 2.75 mg/kg PO q24h; pradofloxacin 3–

4.5 mg/kg PO q24h

Rifampin: 10–20 mg/kg PO q24h or divided BID (maximum 600 mg/day)

Clarithromycin: 7.5–15 mg/kg PO BID

Isoniazid and rifampin: combinations have been used; little is known about their

use in cats; one recent report of treatment (cat) with isoniazid, rifampin, and

dihydrostreptomycin for 3 months noted weight loss but eventual successful

outcome

Isoniazid: 10–20 mg/kg PO (up to 300 mg total) q24h

Ethambutol: 10–25 mg/kg PO q24h

Pyrazinamide: instead of ethambutol; 15–40 mg/kg PO q24h

Dihydrostreptomycin: 15 mg/kg IM q24h

Clofazimine: 4–10 mg/kg PO q24h

Doxycycline: 10 mg/kg PO q24h or divided BID.