Clinical Study Of Late-onset Noninfectious Pulmonary Complication After Allogeneic Hematopoietic Stem Cell Transplantation

Objective:To investigate the incidence, clinical features, risk factors and clinical outcome of late-onset non-infectious pulmonary complications (LONIPCs) following allogeneic hematopoietic stem cell transplantation (allo-HSCT).Method:We retrospectively analyzed 14 cases of late-onset non-infectious pulmonary complications (LONIPCs) in 99 patients who underwent allo-HSCT from April,2000 to July, 2010. The evaluation was based on clinical presentation, radiologic imaging and lung function. Risk factors were assessed by univariate and multivariate statistical regression models. The follow up ended on March 1,2011.Results:14 cases out of 99 patients developed LONIPCs (14.1%), presenting with nonproductive cough and dyspnea at onset. Initial antibiotic treatment did not ameliorate symptoms, but most patients responded well to steroid. The median time interval from transplantation to LONIPCs diagnosis was 382.5 days (range 191～1277 days). Median survival time of patients with LONIPCs from the time of diagnosis was 19.5 months (5-78 months). 10 patients died of progressive respiratory failure (71.4%). All of the patients with LONIPCs developed extensive cGVHD.4 patients underwent the pulmonary function tests, and all of them showed different degrees of obstructive and restrictive ventilatory dysfunction. The common chest CT scan of patients with LONIPCs included ground-glass opacities, regional consolidation and nodular opacities, with bronchiectasis in 12 cases, obvious bulla in 2 cases, pneumomediastinum and subcutaneous emphysema in 8 cases. Multivariate analysis showed that transplants from an unrelated donor and occurrence of extensive chronic GVHD were significantly associated with the development of LONIPCs.Conclusion:We found that the incidence of LONIPCs in this study was 14.1%. The development of LONIPCs was associated with shorter survival, mainly owning to respiratory failure. Considering the poor prognosis of LONIPCs and lack of optimal therapies for this lung complication, the patients with high risk factors should be monitored for their clinical symptoms and lung function in order to recognize and treat this respiratory complication earlier.