Prospective observational study on the clinical characteristics of pulmonary graft-versus-host disease in patients after hematopoietic stem cell transplantation.

In patients undergoing hematopoietic stem cell transplantation (HSCT), pulmonary complications include both infectious and non-infectious conditions. Among these, bronchiolitis obliterans syndrome(BOS) represents a severe manifestation of pulmonary graft-versus-host disease. BOS typically develops within two years after HSCT, with a median time to diagnosis ranging from 6 months to 1 year. However, it may occur at any time between 50 days and 10 years post-transplantation. During the early course of the disease, many patients are asymptomatic; progressive dyspnea and cough subsequently develop, usually over weeks to months. Potential risk factors include chronic graft-versus-host disease, older age, impaired pre-transplant pulmonary function, and early respiratory infections.

The current diagnostic criteria for BOS are still based on the recommendations of the 2014 National Institutes of Health Consensus on chronic graft-versus-host disease. Treatment for BOS remains complex and is supported by limited evidence. In Taiwan, local data on pulmonary complications-particularly BOS-remain insufficient.

We aim to establish a prospective cohort study enrolling approximately 600 participants to analyze the epidemiology, clinical manifestations, pulmonary function changes (including impulse oscillometry), imaging findings, and biomarker alterations associated with pulmonary graft-versus-host disease in Taiwanese HSCT recipients.

Inclusion Criteria:

1. Age>18
2. Will Receive first time Allo-HSCT patients

Exclusion Criteria:

1. Respiratory failure
2. Hemodynamic unstable
3. Pneumothorax or bronchial fistula
4. Acute coronary syndrome in recent 1 month
5. The patient couldn't walk longer than 20 m
6. Severe lower-limb arthropathy
7. The patient couldn't cooperate well
8. Need all-day oxygen supplement
9. The patient received lung transplantation before

At National Taiwan University Hospital and National Taiwan University Hospital Cancer Center

IPD will not be shared due to privacy concerns and limitations specified by the ethics committee/institutional review board.