Triple Combination CFTR TherapyImpact of Triple Combination CFTR Therapy on Sinus Disease.

Inclusion Criteria:

1. Subjects from 18 to 89 years old.
2. Subjects with cystic fibrosis and comorbid chronic sinus disease (historic diagnosis based on physician assessment of signs and symptoms and medical record).
3. Subjects who clinically elect to initiate elexacaftor-tezacaftor-ivacaftor therapy and/or that are ineligible for CFTR modulator therapy based on their genotype, but have class I/II mutations based on sweat chloride > 90 mmol/L.

Exclusion Criteria:

1. Subjects under the age of 18 or over the age of 89.
2. Subjects who do not elect to initiate elexacaftor-tezacaftor-ivacaftor for clinical reasons.
3. Subjects who had sinus surgery within the last 6 months or will have sinus surgery during the study period.
4. Subjects who have had a recent pulmonary exacerbation or viral infection within two weeks of initial visit.