Bronchial stenosis after lung transplant: Risk factors and clinical outcomes

Bronchial stenosis is a known complication after lung transplantation, but risk factors remain incompletely understood. We identified predictors of bronchial stenosis requiring bronchoscopic intervention, with a focus on post-transplant bacterial infections, and its impact on clinical outcomes.

We conducted a retrospective cohort study of 342 adult lung transplant recipients at a single center between 2017 and 2023. Bronchial stenosis was defined as localized airway narrowing requiring intervention. Clinical, perioperative, and infectious variables-censored to precede the onset of stenosis-were analyzed using univariate and multivariable logistic regression. Outcomes included survival, acute cellular and antibody-mediated rejection, and chronic lung allograft dysfunction (CLAD).

Thirty-four patients (9.9%) developed bronchial stenosis requiring intervention. Multivariable analysis identified male sex (OR: 2.77, 95% CI: 1.13-6.79, p = 0.0261), pulmonary graft dysfunction (PGD) (OR: 3.45, 95% CI: 1.23-9.69, p = 0.0190), length of index hospitalization (OR: 1.01, 95% CI: 1.00-1.02, p = 0.0479), and any positive post-transplant bacterial respiratory culture-prior to onset of stenosis-(OR: 3.97, 95% CI: 1.67-9.48, p = 0.0019) as independent risk factors. Pneumonia and colonization with Pseudomonas aeruginosa or other gram-negatives were strongly associated with stenosis, while Staphylococcus aureus infections and colonization were not. Bronchial stenosis did not significantly impact survival, rejection, or CLAD incidence.

Bronchial stenosis following lung transplantation is associated with PGD and bacterial airway infections, particularly Pseudomonas species or other gram negatives. These findings support an association between early gram-negative bacterial airway infections and bronchial stenosis and highlight the need for infection prevention and further prospective studies to clarify causal mechanisms and guide targeted interventions.