Pulmonary hypertension associated with pulmonary occlusive vasculopathy after allogeneic bone marrow transplantation

Background. Pulmonary vasculature abnormalities, including pulmonary veno-occlusive disease, have been demonstrated in marrow allograft recipients. However, it is often difficult to make a correct diagnosis of pulmonary lesions. Methods. An open lung biopsy was performed on a patient who developed severe pulmonary hypertension after bone marrow transplantation for T-cell lymphoma. Results. An open lung biopsy specimen demonstrated pulmonary arterial occlusion due to intimal fibrosis and veno-occlusion. The most striking alteration was partial to complete occlusion of the small arteries by fibrous proliferation of the intima. Conclusion. High-dose preparative chemotherapy and radiation before transplantation are thought to have contributed to the development of vasculopathy in this patient, because arterial occlusion by intimal fibrosis and atypical veno-occlusion are often associated with lung injury due to chemoradiation. An open lung biopsy is essential for diagnosing pulmonary vascular disease presenting signs compatible with post-transplantation pulmonary hypertension.