Eradication of Mycobacterium abscessus infection in cystic fibrosis with initiation of Elexacaftor/Tezacaftor/Ivacaftor.

Mycobacterium abscessus is a nontuberculous mycobacterium that is often multi-drug resistant, difficult to eradicate and associated with a rapid decline in lung function in cystic fibrosis (CF). Elexacaftor/Tezacaftor/Ivacaftor (ETI) is a combination CFTR modulator that improves lung function and decreases exacerbations, but limited data exists about its impact on respiratory infections. A 23-year-old male with CF (F508del, unknown) was diagnosed with Mycobacterium abscessus subspecies abscessus infection. He completed 12-weeks of intensive therapy, followed by oral continuation therapy. Antimicrobials were later discontinued for optic neuritis secondary to linezolid. He remained off antimicrobials with persistently positive sputum cultures. He then initiated ETI, and bronchoscopy eight months later suggested eradication of M. abscessus. By modulating CFTR protein function, ETI may improve innate airway defence mechanisms, facilitating the clearance of infections such as M. abscessus. This case highlights the potential positive implications of ETI on the challenging treatment of M. abscessus infections in CF.