# Tracheal Diverticula in People with Cystic Fibrosis on Elexacaftor/Tezacaftor/Ivacaftor: An Italian Multicenter Retrospective Study

## TL;DR

This study reports on three cases of tracheal diverticula found in cystic fibrosis patients receiving a new triple therapy drug combination.

## Contribution

The study is one of the first to report the occurrence of tracheal diverticula in cystic fibrosis patients treated with Elexacaftor/Tezacaftor/Ivacaftor.

## Key findings

- Three out of 268 cystic fibrosis patients on ETI therapy were found to have tracheal diverticula via chest CT scans.
- Endoscopic confirmation was obtained in one of the three cases.
- All patients were using inhaled colistimethate, with two having chronic Pseudomonas aeruginosa colonization.

## Abstract

Background/Objectives: Cystic Fibrosis (CF) is an autosomal recessive genetic disorder caused by variants in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) protein. Recently, a targeted therapy for CF has been developed, represented by the CFTR modulators that enhance or restore the function of the CFTR protein. The most recent is the combination of three modulators, Elexacaftor, Tezacaftor, and Ivacaftor (ETI). This study describes the presentation, management, and follow-up of tracheal diverticulum (TD) in pwCF receiving ETI therapy. Methods: This retrospective study included people with CF (pwCF) on ETI treatment and followed up in two CF Italian centers who developed an asymptomatic TD, diagnosed incidentally at chest CT scan. Results: Among 268 pwCF receiving ETI, three (1.19%) were diagnosed with TD identified after chest CT and were included in this study. Endoscopic confirmation was obtained in one patient. All patients were on inhaled colistimethate, two of them for chronic Pseudomonas aeruginosa colonization, and one undergoing eradication therapy. Conclusions: TD may be identified in chest CT obtained in pwCF in treatment with ETI. Further studies and a longer follow up are needed to confirm these findings.