The timing of intravenous antibiotics and clinical outcomes of <i>Mycobacterium abscessus</i> complex lung diseases

&lt;sec&gt;&lt;title&gt;BACKGROUND&lt;/title&gt;The importance of early intravenous (IV) antibiotic use for Mycobacterium abscessus complex lung diseases (MABC-LD) treatment remains unknown.&lt;/sec&gt;&lt;sec&gt;&lt;title&gt;METHODS&lt;/title&gt;A retrospective multi-centre observational study was conducted in Taiwan. Patients who were diagnosed with and received treatment for MABC-LD from January 2007 to April 2021 were included. Treatment outcome was defined as modified microbiological cure of MABC-LD.&lt;/sec&gt;&lt;sec&gt;&lt;title&gt;RESULTS&lt;/title&gt;Of the 89 enrolled patients, 34 (38.2%) received IV antibiotics as part of the treatment regimen. The median time to IV initiation was 1 day (IQR 1–49); 24 (70.6%) of these patients received IV agents within 4 weeks, defined as early-use. Forty-two (47.2%) patients achieved modified microbiological cure. In the multivariable logistic analysis, early IV antibiotic use was an independent factor associated with modified microbiological cure (aOR 5.32, 95% CI 1.66–17.00), whereas high radiological score (aOR 0.86, 95% CI 0.73–1.00) demonstrated negative association.&lt;/sec&gt;&lt;sec&gt;&lt;title&gt;CONCLUSIONS&lt;/title&gt;In the present study, early use of effective IV antibiotic was prescribed in a low percentage (27%) for MABC-LD. By contrast, early IV antibiotic use was correlated with higher microbiological cure than were late or non-use. Future larger and prospective studies are needed to validate the association.&lt;/sec&gt;