Investigators from Queensland’s Children’s Hospital, South Brisbane, Australia, and Griffith University, Gold Coast, Australia, conducted a case-control study to assess the association between childhood tracheomalacia and bronchiectasis. Cases were children ≤18 years old with radiographically confirmed bronchiectasis, unrelated to cystic fibrosis (CF), who were seen at a single pediatric center in Australia, enrolled in the Australian Bronchiectasis Registry, and chosen at random from the registry. Only patients who had a chest CT obtained between 2012 and 2018 and who underwent flexible bronchoscopy (FB) within 4 weeks of the CT were eligible as cases. Bronchiectasis was defined using specific radiographic findings and consistent clinical characteristics. Controls were children who had a recent bone marrow transplant and/or cancer and who had a chest CT and FB performed during the same time period for evaluation of febrile neutropenia. Two controls were chosen for each case study participant. For cases, the cause of bronchiectasis was recorded, and for controls, the underlying disorder was noted. The videos from FB in study children were reviewed by an experienced respiratory pediatrician, blinded to the patient’s case/control status, who noted the presence of any tracheomalacia (any-TM), defined as tracheal shape abnormality during expiration, or tracheomalacia, defined by the European Respiratory Society as >50% expiratory reduction in cross-sectional area (ERS-TM). Logistic regression was used to assess the relationship of any-TM and ERS-TM with bronchiectasis. Multivariable analyses adjusting for age, sex, and ethnicity also were conducted.
A total of 45 cases and 90 controls were enrolled in the study. Cases were younger than controls (median ages 2.6 years and 7.8 years, respectively). Among cases, the etiology of bronchiectasis was post-infectious in 17 (38%), idiopathic in 15 (33%), aspiration in 7 (16%), primary ciliary dyskinesia in 3 (7%), and other causes in 3 (7%). For control children, 69 (77%) had a hematologic malignancy, and 9 (10%) were post-bone marrow transplant. On FB, 14 (31.3%) cases had any-TM compared to 3 (3.3%) controls (OR, 13.1; 95% CI, 3.5, 48). There were 9 cases and 0 controls with ERS-TM (OR, 30.1; 95% CI, 4.6, ∞). Multivariable analyses demonstrated both age and tracheomalacia were associated with bronchiectasis. After adjusting for age, tracheomalacia remained significantly associated with bronchiectasis using the any-TM definition (OR, 13.2; 95% CI, 3.2, 55).
The authors conclude that tracheomalacia is associated with childhood bronchiectasis.
Dr Lesser has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.
Bronchiectasis is commonly defined as airway dilatation on chest CT and occurs as a consequence of chronic bronchial inflammation and infection, leading to lung injury that can be irreversible.1 While bronchiectasis most commonly occurs with CF, other diseases such as primary ciliary dyskinesia, immunodeficiency, severe pulmonary infection,...