Impact of elexacaftor/tezacaftor/ivacaftor on respiratory colonization in an adult cystic fibrosis clinic.

BACKGROUND: Little research has been completed on the correlation between cystic fibrosis (CF) modulator therapy and its effect on respiratory cultures in CF patients. This study evaluated the effect of elexacaftor/tezacaftor/ivacaftor (ETI) on respiratory colonization with Pseudomonas aeruginosa. METHODS: This single center, IRB approved, retrospective chart review compared patient data two years immediately prior to ETI initiation with patient data two years post-initiation from January 2017-December 2022. Patients were included in the study if they were at least 18 years old with a diagnosis of CF and had at least one month of ETI dispensed, at least one sputum culture obtained, and were currently on ETI. Those who had not been seen since ETI initiation or received a bilateral lung transplant were excluded. The primary outcome was rate of patients with respiratory colonization post-ETI. Colonization was defined as two or more positive P. aeruginosa cultures in a 12-month period. Decolonization was defined as three consecutive negative P. aeruginosa cultures after previous colonization. Key secondary outcomes included average time to discontinuation of mucolytic therapy and relative risk of pulmonary exacerbation. RESULTS: A significant reduction (p<0.001) in colonization with P. aeruginosa was observed with 49 patients in the pre-ETI group compared to 25 in the post-ETI group meeting the definition of colonization (n=79). Average time to discontinuation of mucolytic therapy was 14 months (p=0.002). Relative risk of pulmonary exacerbation was 4.80 (p<0.001). CONCLUSIONS: ETI use resulted in reduced colonization with P. aeruginosa, discontinuation of mucolytic therapy, and decreased frequency of pulmonary exacerbation.

A 13-Year-Old Male Patient With Severe Multifocal Pneumonia and Bronchiectasis That Required Extracorporeal Membrane Oxygenation.

CASE PRESENTATION: A 13-year-old male patient with intermittent asthma and joint hypermobility presented to the ED in acute hypoxemic respiratory distress. He reported experiencing cough, increased work of breathing, and worsening chest pain for 3 days before presentation. He also reported fatigue and decreased appetite for 2 weeks. He had no known fever, myalgias, or recent weight loss. His medical history included two hospitalizations during early childhood for viral respiratory illnesses, one of which required intubation at 8 months of age. He had a gastrostomy tube placed shortly after his hospitalization because of failure to thrive secondary to aspiration based on a swallow study. His weight gain and growth improved with adequate nutrition, and his gastrostomy tube was removed at 2 years of age. His newborn screen, which included immunoreactive trypsinogen, was normal. He was noted to have hypermobile joints on physical examination at a clinic visit in childhood, but his examination results were not concerning for a hypermobility syndrome, and further diagnosis was not pursued. His parents endorsed that he has been a "healthy child" overall other than the occasional cough, which was attributed to asthma. His lifestyle was described as sedentary; he did not play any sports or have any unusual hobbies. He did not take any daily medications and no environmental exposures were reported. There was no family history of pulmonary, autoimmune, or connective tissue disease.