Amikacin liposomal inhalation suspension versus injectable streptomycin in patients with refractory pulmonary Mycobacterium avium complex disease: A single-center, retrospective cohort study

Amikacin liposomal inhalation suspension (ALIS) and injectable streptomycin (SM) are aminoglycosides used in addition to guideline-based therapy (GBT) in patients with Mycobacterium avium complex lung disease (MAC-LD). However, no studies have compared the efficacy of ALIS and injectable SM in patients with refractory MAC-LD. The current study aimed to retrospectively compare the sputum culture conversion rates and the treatment continuation probability of ALIS and injectable SM in patients with refractory MAC-LD. This study included patients with refractory MAC-LD who were diagnosed with MAC-LD at the Department of Respiratory Medicine at Toho University Medical Center Sakura Hospital from April 2010 to May 2023, and who could not achieve negative sputum culture conversion after GBT for at least 6 months resulting in new treatment with ALIS or injectable SM. The medical records of the patients were retrospectively reviewed. Then, the sputum culture conversion rates up to 6 months and the treatment continuation probability up to 6 months between patients receiving ALIS and those receiving injectable SM were compared. Twenty-three patients with MAC-LD were eligible for present study. Eleven patients were treated with ALIS and 12 with injectable SM. Four (36%) patients treated with ALIS and 2 (17%) with injectable SM achieved negative sputum culture conversion, but there was no statistically significant difference between 2 groups (P = .37). The continuation probability up to 6 months of the patients treated with ALIS was significantly higher than that of patients treated with injectable SM (two-tailed log-rank test hazard ratio: 0.058, 95% confidence interval: 0.018-0.185, P = .0001). The most common cause of injectable SM discontinuation was hospital visit difficulty. ALIS and injectable SM had similar sputum culture conversion rates. However, the former had a higher continuation probability than the latter.