Mechanisms of exercise limitation and pulmonary rehabilitation in patients with cystic lung diseases.

Introduction: The main diffuse cystic lung diseases (DCLD) include lymphangioleiomyomatosis (LAM), pulmonary Langerhans cell histiocytosis (PLCH), Birt-Hogg-Dubé syndrome, and lymphocytic interstitial pneumonia. Exercise limitation is frequent and secondary to multiple mechanisms in DCLD. Some studies addressed mechanisms for exercise limitation, field tests, and pulmonary rehabilitation (PR) in DCLD.

Areas covered: This review aims to present the main mechanisms that determine exercise limitation, the responses of patients in field tests, and the details regarding the safety and efficacy of PR in DCLD, with emphasis on LAM and PLCH. A search on the issue was performed in the MEDLINE and SciELO databases between 27 November 2024 and 20 February 2025. Manuscripts were reviewed and important topics were included in this review.

Expert opinion: Reduced exercise capacity is common and multifactorial, including ventilatory, cardiocirculatory, and peripheral limitations, pulmonary hypertension (PH), and impaired gas exchange in LAM and PLCH. Variables from field tests are correlated with pulmonary function tests, and PR is safe and beneficial in LAM. Further studies are necessary to evaluate exercise in other DCLDs, the impact of other therapeutic modalities on DH, hypoxemia, and exercise-induced PH in LAM and PLCH, and the safety and benefits of PR mostly in PLCH.