Safety of IV amikacin in the treatment of pulmonary non-tuberculous mycobacterial disease

Background and objective: Pulmonary non-tuberculous mycobacterial (NTM) disease has a high mortality rate and often requires treatment with intravenous amikacin. We report on safety data in patients treated with intravenous amikacin for pulmonary. Methods: A retrospective observational study (2002-2012) was performed including 45 patients that met American Thoracic Society criteria for pulmonary NTM disease and were treated with intravenous amikacin at three hospitals in Brisbane, Australia. The aim was to define the rates of common adverse effects, the patient and regimen factors associated with these adverse effects and describe the rates of treatment success and associated factors. Results: Forty-five patients (34 women; median age 63 years) were treated for Mycobacterium intracellulare (25), Mycobacterium abscessus (13), Mycobacterium avium (6) and Mycobacterium fortuitum (1) using multi-drug therapy that included IV amikacin. Transient ototoxicity was seen in eight (18%) but long-term ototoxicity was seen in only three (7%). There were no cases of nephrotoxicity and no long-term vestibulotoxicity. Sustained culture conversion at 6 months was only found in 17 (38%), however, the majority (34 patients, 76%) had a clinical response to treatment determined by an improvement in symptoms. Conclusion: Carefully selected and closely monitored patients with pulmonary NTM can be treated using IV amikacin safely with low rates of toxicity. No pretreatment patient or regimen factors were predictive of toxicity or treatment success in this small cohort. Lower treatment success rates were found than previous trials suggest there is a difficult balance in this patient group between treatment success and toxicities.