Mycobacterium kansasii infection
For general information on nontuberculous mycobacterial infections, see Diagnosis of nontuberculous mycobacterial infections and Approach to managing nontuberculous mycobacterial infections.
Mycobacterium kansasii causes a chronic pulmonary infection that resembles tuberculosis. Pyrazinamide resistance is universal. Rifampicin is the mainstay of treatment if the isolate is susceptible. For rifampicin-susceptible isolates, use:
isoniazid 300 mg (child: 10 mg/kg up to 300 mg) orally, daily12. For dosage adjustment in adults with kidney impairment, see isoniazid dosage adjustment Mycobacterium kansasii isoniazid
PLUS
rifampicin 600 mg (adult less than 50 kg: 450 mg; child 50 kg or more: 600 mg; child less than 50 kg: 15 mg/kg up to 450 mg) orally, daily. For dosage adjustment in adults with kidney impairment, see rifampicin dosage adjustment Mycobacterium kansasii rifampicin
PLUS
ethambutol (adult and child) 15 mg/kg orally, daily 3. For dosage adjustment in adults with kidney impairment, see ethambutol (daily regimen) dosage adjustment. Mycobacterium kansasii ethambutol
Treatment duration is usually 18 months; however, continue treatment until the patient’s sputum is culture-negative for at least 12 months.
Monitor vision because ethambutol can cause visual adverse effects (see Monitoring tuberculosis therapy).
For detailed information on the management of M. kansasii pulmonary infections, see the British Thoracic Society Guidelines for the Management of Non-tuberculous Mycobacterial Pulmonary Disease (NTM-PD) [URL].